Upon my retirement in June of 2008, the digital conversion of this paper was completed after the many years since its acceptance & publication and is hereby dedicated to the following individuals. Each gave of their extraordinary assistance to my career within the marine biological sciences combined with the success of my K-12 outreach science program “OCEAN TREASURES”during its 19-year presentation span to educational communities worldwide and will always be forever truly appreciated:
Dr. Michael A. Bigg
Stan L. Waterman
Dr. Erich J. Hoyt
Dr. Lanny H. Cornell
Dr. John K.B. Ford
Dr. Richard M. Sears
William W. Rossiter
Dr. Robbins W. Barstow
Dr. Miguel A. Iñiguez
Dr. Arthur B. Mansfield
Dr. Robin W. Baird
Dr. Graeme M. Ellis
Dr. Ian B. MacAskie
Dr. J. Stephen Leatherwood
Dr. Paul J. Spong
Kenneth C. Balcomb III
Thomas A. Lincoln
Dr. David E. Sergeant
José Truda Palazzo, Jr.
Dr. John D. Hall
Dr. Johann W. Sigurjonsson
Arnold W. Raeder
Dr. John N. Lien
Dr. R.S. Lal Mohan
Donald A. Sineti
Dr. Ivan D. Christensen
Dr. Edward D. Asper
Peter S. Benchley
Dr. Robert S. Kurson
Dr. Samuel H. Gruber
Dr. Peter C. Beamish
Dr. Murray S. Newman
Dr. Marilyn E. Dehlheim
Dr. Linda R. Wilson
Dr. Christian T. Lockyer
Kenneth S. Norris
Dr. Pamela J. Stacey
Dr. Ingrid N. Visser
Dr. Berne J. Würsig
Dr. Robert L. Brownell
Rodney E. Fox
Dr. James D. Darling
Dr. Christoph C. Guinet
Dr. Charles A. Mayo
Dr. James E. Heyning
Dr. Richard R. Reeves
Dr. Jon E. Krakauer
Dr. William E. Schevill
Dr. Susan H. Shane
Dr. William R. Watkins
Oceanic Marine Mammal Research
University of British Columbia
FIELD RESEARCH, CASE STUDIES and
GEOGRAPHIC VARIATIONS of the
KILLER WHALE “Orcinus orca”
Gregory R. Mann
The Killer Whale (Orcinus orca) is well known worldwide, as a predator of other oceanic marine species including the larger rorqual whales. Not all known behavioral interactions however between Killer Whales and other oceanic marine species results in direct predation. Other forms of documented species interactions include harassment by Killer Whales, multiple species feeding within the same area, smaller cetaceans playing around the known predator who apparently ignores a possible food source and even apparently unprovoked attacks upon Killer Whales by larger pennipeds. These other types of interactions are more common than most people believe. The goal of this paper is to present such scientific information which will conclude that Killer Whale vs Marine Mammal interactions are extremely complex, involving many different factors which conducted field research by the scientific community is just beginning to understand.
At the outset, I wish to acknowledge and sincerely thank the prestigious members of the Doctoral Review Board of the University of British Columbia, for the opportunity to present this paper as a candidate for my Ph.D. in Oceanic Marine Biology.
Only one species of Killer Whale is recognized in the world. However, there appears to be many localized races that differ in appearance, behavior and other lesser-known biological traits. Soviet biologists in September 1989, proposed a second species (Orcinus glacialis) from the Antarctic region, which they have characterized as having a smaller size and a variety of differences in diet, reproduction, appearance and behavioral traits.
The submitted new species has not yet been fully accepted by the world’s scientific community and this species is considered as a distinctive race of the same known species of Killer Whale. What is believed in the world’s scientific community is that there are indeed two separate races of the species. Known as “residents” and “transients”, both species live off the coastline of the Pacific Northwest region and are known to differ in appearance as well as many other biological aspects.
Possibly the most defiled of all animals on planet Earth, the Killer Whale has been branded by mankind as a ferocious and indiscriminate killer of oceanic marine wildlife and occasionally, even humans. The scientific name given to his oceanic marine mammal, even translates into a fearful and descriptive message. From earliest times, the Latin connotation means simply “the bringer of death”.
Moreover, the word “Orca” as used in the nomenclature of the general public simply denotes in Latin as “Whale” and thus, is inappropriate for further use in this paper. The word itself was created by the Sea World facilities several years ago, as a marketing tool used in their overall display especially marketing towards the newborn Killer Whales at their various venues. Instead of marketing the newborns as “Baby Killers”, they could simply advertise them as “Baby Orcas” which in the world of marketing would ease the harshness of the word from a general public view.
In recent history, large numbers of these powerful marine mammals were slaughtered by humans simply because these cetaceans lived within the same geographical areas where fishermen set their nets. Scientific studies conducted within the field and a 21-year history of Killer Whales held captive in various worldwide oceanographic facilities, now paints a completely different picture of this oceanic marine predator. Many scientists now recognize Killer Whales, as an important member of the oceanic food chain and a vital link of the overall ecology of the world’s ocean habitat in which they dwell.
Killer Whales have shown very little fear of humans and current research has shown of confirmed reports of Killer Whales having killed a human in the wild. Marine biologists who have worked and studied these small cetaceans at marine wildlife parks, have recognized this species of having an extremely high level of intelligence and cooperative behavior. It remains very difficult however, to discuss this marine animal without using some type of superlatives.
Writers for centuries have described the Killer Whale as the fastest, strongest, deadliest and highest form of intelligence within the world’s oceans. There is strong evidence to support the use of varied descriptive terms but on the other hand, the widespread opinion that any swimmer or diver encountering a Killer Whale in the open ocean is doomed to the fate of Jonah, seems to be entirely without supporting evidence.
Undoubtedly the smaller family of cetaceans which includes the Killer Whale, is the most intelligent group of animals among all oceanic marine species. Researchers worldwide, have never truly had the quality opportunities to test this specie’s learning capacities, even under captive conditions but other small cetaceans have been tested extensively and are thought to possess a higher degree of intelligence than dogs. It should be emphasized however, that no reliable evidence substantiates the sensational claim of a few researchers and writers, that porpoises and dolphins may be as smart as humans. It does seem to be true however, that Killer Whales share at least one dubious distinction with humans, the so-called “killer instinct”.
Among all the world’s land & marine mammals, these are the only species that are known to kill other animals for the sheer sport of killing. Whether or not such behavioral traits denote a higher degree of intelligence remains an unsettled and unsettling proposition.
The Killer Whale is the largest member of the small-toothed cetaceans known in scientific terminology as Ocean Dolphins (Delphinidaes). Often called “Grampus”, “Blackfish”, “Broadfin”, “Fatchopper” or “Whalekiller”, these oceanic marine mammals are sometimes confused when sighted in the open ocean with the False Killer Whale (Psuedorca crassidens) or the Long-Finned Pilot Whale (Globicephala melanena). In pure fact, there is little reason to mistakenly identify any other cetacean species for a Killer Whale.
It’s large but streamline form and striking black & white patterns combined with its known swimming and feeding behaviors, is quite unlike any other form of oceanic marine wildlife. Dark black over most of its dorsal & lateral surfaces, the Killer Whale has a small oval-shaped white patch directly above and behind each of its eye regions. The ventral surface feature of the body is brilliantly white in color.
In the abdominal region, dorsal-lateral to the dorsal fin, a pale gray patch classified as the “saddle” is located which researchers have found to be an individual whale’s identifying mark or id tag, much like a human finger-print. Dr. Michael A. Bigg is given full credit to the discovery of this break through documentation which has led to other members of the cetacean family similarly being recorded in a like manner. Due to this uniquely difference among Killer Whales, each animal can be classified and cataloged during population census or pod identification photographing.
Adult males or bulls in particular, can hardly be mistaken for any other type of animal, which lives in the world’s oceans when sighting its narrow, pointed dorsal fin that may extend to 7’ above the back.
Repelling a popular belief, the dorsal fin contains no type of bone or skeletal structure and is instead, made entirely of cartilage much in the same structure as the human nose region. The dorsal fin is sometimes seen bent over or wavy especially in older males, due to the increased weight by growth during an individual’s lengthy life span and has nothing to do with whether the individual is captive or not.
Females or cows have a much smaller curved dorsal fin, which is very similar to the dorsal fins of several other small cetacean species for which mistaken identifications often occur. The females however, possess the same basic coloration markings, which match directly with the males.
Killer Whales are very well equipped for their unique lifestyle, with 34 conically-type teeth within their massive jaw. Capable of grasping and swallowing the entire body of a porpoise, seal or dolphin, this fact about Killer Whales made for an individual case that was reported and even now, is often misquoted and embellished. Dr. Everhard J. Slijper of the Icelandic Research Institute wrote in his classic book “Whales & Dolphins”, of 32 Pacific Harbor Seals (Phoca vitculina) combined with other various dolphin species being removed from the stomach of a 24’ male taken in the Bering Sea off the southern coastline of Alaska.
In a much earlier documentation published in which my research has shown to have truly grown with rumors over the years, Dr. Daniel F. Eschricht reported a scientific result from a March 1861 field expedition. Dr. Eschricht’s field journals recorded the discovery during a dissection of pieces of 13 Ribbon Seals (Phoca hispida) as well as other various porpoises & dolphin species among the stomach contents of a 29’ bull taken off the eastern coastline of Iceland. These accounts are often misquoted and have been in recent past history, a prime source of the Killer Whale’s bad reputation.
In all know physical characteristics, the Killer Whale appears to be very successful from both a scientific & evolutionary point of view as well as one of the most advanced of all marine or land animals. Furthermore, they seem to have no natural predators other than humans. Even the whaling industry seldom bothers to harvest these small cetaceans, due largely to their rather limited body oil content. At present however, Japan and the Soviet Union are still conducting the largest fishery of Killer Whales for harvest. Located near the continent of Antarctica, the Russian & Japanese whaling fleets take up to 600 animals per year. Along the coastal regions of Iceland and Greenland, countless conflicts between Killer Whales and local fishermen have resulted in the periodic slaughter of hundreds of these marine mammals. In the past decade however, the Icelandic government has approved the creation of a live-capture fishery of Killer Whales to transplant them into remote northern waters.
Some of these captured animals are also shipped to the United States as well as other countries, for display and scientific research in many marine-life oceanography facilities. To discuss this research a step further, the International Whaling Commission (I.W.C.) as a direct result of an immediate moratorium passed during their 1980 Annual World Conference, completely banded all commercial whaling of smaller cetaceans including the Killer Whale.
The fact that Killer Whales are not more common however, is not a direct result of recent whaling methods. Ongoing research has discovered that their slight numbers may be due to the limited effect upon their available food supply or quite possibly, be a direct effect of a higher than normal birth mortality rate.
This is probably the most cosmopolitan of all cetaceans and can be seen in literally any marine region. Sightings of “Orcinus orca” occur throughout all oceans and contiguous seas, from equatorial regions to the polar pack-ice zones and may even ascend rivers. However, it is most numerous in coastal waters and cooler regions where productivity is high.
In the Atlantic it ranges north to Hudson Strait, Lancaster Sound, Baffin Bay, Iceland, Svalbard, Zemlya Frantsa Iosifa and Novaya Zemlya; its range includes the Mediterranean Sea. In the Pacific it ranges north to Ostrov Vrangelya, the Chukchi Sea, and the Beaufort Sea. In the Southern Ocean, the range extends south to the shores of Australia and the Philippines, South Africa, South America and Antarctica, including the Ross Sea at 78°S.
Data from the central Pacific are scarce. They have been reported off Hawaii, but do not appear to be abundant in these waters.
Distribution of Orcinus orca: this species is found in all regions of the world, particularly in the Polar Regions
In the north-eastern Pacific, photo-identification studies yielded at least 850 individuals in Alaska, 117 off the Queen Charlotte Islands, 260 “resident” whales and 75 “transient” whales off eastern and southern Vancouver Island, 184 off the coasts of California and 65 off the Mexican west coast. Note that photo-identification techniques result in a minimum count of animals. In a more recent estimate, comes to a total population count of 1,500 Killer Whales in the northeastern Pacific. In the North Atlantic, questionnaire surveys yielded 483 to 1,507 Killer Whales for Norwegian coastal waters. Sightings in the eastern North Atlantic gave rough estimates of around 3,100 Killer Whales for the area comprising the Norwegian and Barents Seas, as well as Norwegian coastal waters and some 6,600 whales for Icelandic and Faeroese waters. Off the Japanese coast the estimate is 1200 individuals north of 35°N and 700 south of 35°N. For Antarctica, the most recent estimate is 80,400 Killer Whales south of the Antarctic convergence and for the Southern Indian Ocean, issued reports show a strong decline in the coastal waters of Possession Island between 1988 and 2000.
Sightings range from the surf zone to the open sea, though usually within 800 km of the shoreline. Large concentrations are sometimes found over the continental shelf. Generally, Killer Whales prefer deep water but they can also be found in shallow bays, inland seas and estuaries but rarely in rivers.
They readily enter areas of floe ice in search of prey. Resident Killer Whales in Pacific Northwest waters use regions of high relief topography along Salmon migration routes, whereas Transient Killer Whales forage for pennipeds in shallow protected waters.
In the Pacific Northwest, calving occurs in non-summer months, from October to March. Similarly in the Northeast Atlantic, it occurs from late autumn to mid-winter. Pods of resident Killer Whales in British Columbia and Washington represent one of the most stable societies known among non-human mammals; individuals stay in their natal pod throughout life. Differences in dialects among sympathetic groups appear to help maintain pod discreteness. Most pods contain 4-55 whales with resident pods tend to be larger than those of transients. Social organization can be classified into communities, pods, sub pods, and matriarchal groups: a community is composed of individuals that share a common range and are associated with one another; a pod is a group of individuals within a community that travel together the majority of time; a sub pod is a group of individuals that temporarily fragments from its pod to travel separately; and a matriarchal group consists of individuals within a sub pod that travel in very close proximity. Matriarchal groups are the basic unit of social organization and consist of whales from 2-3 generations. Membership at each group level is typically stable for resident whales, except for births and deaths.
Being a apex predator, the Killer Whale utilizes the available resources in a complex fashion. Killer Whales often associate with other marine mammals (cetaceans and pennipeds) without attacking summarize that the typical size of transient Killer Whale groups is consistent with the maximization of energy intake hypothesis. Larger groups may form for the occasional hunting of prey other than Harbor Seals, for which the optimal foraging group size is probably larger than three; and the protection of calves and other social functions.
Killer Whales are best known for their habits of preying on warm-blooded animals: they have been observed attacking marine mammals of all groups, from Sea Otters to Blue Whales except River Dolphins and Manatees. However, they often eat various species of fish and cephalopods and occasionally seabirds and marine turtles. Pods often co-operate during a hunt. Relationship with the prey is complex: pods tend to specialize and may frequently ignore potential prey as well as observations of Killer Whales feeding on Atlantic Herring (Clupea harengus) in a fjord in northern Norway using underwater video. The whales co-cooperatively herded Herring into tight schools close to the surface.
During herding and feeding, Killer Whales swam around and under a school of Herring, periodically lunging at it and stunning the Herring by slapping them with the underside of their flukes while completely submerged. While Herring constitute the whales’ main diet in Norwegian waters, Cod, Flatfish and Cephalopods are the primary components off Japan.
In Puget Sound, the main food of resident Killer Whales during the summer and fall is Salmon. Most food items are swallowed whole. However, when whales attack larger prey, they rip away smaller pieces of flesh and then consume them. The tongues, lips, and genital regions of baleen whales seem to be the favored parts. Killer Whales consume fish of commercial importance. Troll catches of salmon show a decline when Killer Whales are in the area and damage to fishing gear has also been reported. Off Iceland, Killer Whales are attracted to Herring operations. Long line fisheries interactions involving Killer Whales have also been observed. Killer Whales are known to follow fish-processing vessels for many miles feeding off discarded fish. In the Bering Sea, the same pod of whales was reported to follow a vessel for 31 days for approximately 1600 km.
FIELD RESEARCH DEVELOPMENTS
Extensively conducted field research and subsequent data has shown that a dominant female leads a typical Killer Whale pod or family. All offspring including the males remain with their mother throughout a normal life span. When the matriarch female dies or becomes to old to reproduce, the next oldest female usually the oldest daughter assumes the role as pod leader.
A cow generally produces one calf every two years, with a standard gestation period lasting from 13-16 months in length. The female’s mammary glands are located on the underside of the body near the tail. Strong muscles allow her to squirt large quantities of extremely rich milk into a calf’s mouth as it dives beneath her. Newborn calves are on the average, about 6’ in length and an estimated 400 lbs at birth. Immediately after a birth, the attending females of the pod act as Nannies to form a type of living-nursery as well aid to protect the infant from predatory sharks and occasionally even the males of the pod and assist with the overall care of the newborn.
Bulls attain a known average length of 26’ but there have been recorded sightings of lengths obtaining over 30’+. The average normal weight of a male is an estimated 7-8 tons but individuals have been recorded from cropping captures of 9-10 tons in weight. Each side frontal flipper known as a “pectoral fin” is extremely broad and rounded, like a ping-pong paddle.
Each fin on an average adult bull, may reach a length of 7’ with an average width of as much as 4’ across. The overall width of the tail flukes from tip to tip on an average male, may extend an approximated 9’ across. The coloration, although previously mentioned, vastly changes in the young. The described white pattern areas are often pale-yellow to light brown during an infant’s first years.
Although extremely rare, all-white individuals have been sighted and even captured. In April 1970, field specialists of Washington’s “Sealand of the Pacific” captured such an animal and held it in their holding facility at Peddler Bay on the British Columbia mainland. The captured “albino” Killer Whale was nicknamed “Chimo” and was kept alive in captivity until she died of a parasitic infection in August 1973.
Little is known of the breeding habits of Killer Whales. From evidence collected during varying stages of fetus development taken from females commercially by Japanese & Soviet whaling fleets, mating appears to occur throughout the entire year. It is also believed, that the species is perhaps polygamous, mating for life with several females of an individual pod. The male’s penis is completely retractile and on a 22’ bull taken in the Sea of Japan, measures 4.5’ in length and was 2.5’ in circumference. A chance aerial photograph was taken by Dr. Siskan Tukjashima of Japan’s “Kamogawa Marine Mammal Research Center” in June 1967, which revealed a pair in copulation belly to belly near the surface of the water.
Juveniles are extremely playful, cavorting about the adults with apparent youthful enthusiasm. Observers have reported seeing young Killer Whales charging quickly at the heads of the adults resulting in an adult catapulting the calf into the air completely out of the water with their powerful tails. Non-sexually active young males often travel on the outside fringes of the remaining pod members, until they reach stable sexual maturity at approximately 14-years of age. Occasionally while traveling, Killer Whales will leap fully extended above the waterline known as “breaching” and fall onto their sides with a tremendous splash. An individual weighting 8 tons must achieve an exit speed from the water of approximately 30’ per second to clear the surface completely.
The overall purpose of such aerial traits is not completely understood, but some experts believe that it represents an act of an efficient predator with time for play or could be quite simply, another form of communication to other pod members.
While diving, an individual may slap the water’s surface resoundingly with its tail flukes known as “lob-tailing” which is believed to be still another form of pod communication. According to Kenneth C. Balcomb III, Executive Director for the “Center for Whale Research”, most dives are rather short in duration approximately 30 seconds or less. About every fifth dive however, results in a longer duration and while especially feeding on a school of fish, may be expanded from 1-4 minutes in length. During these longer duration dives, a Killer Whale can travel several hundred yards before resurfacing.
Individuals classified as “Transients” unlike the better-known “Resident” population species, have been recorded to register extremely deep dives lasting between 10-15 minutes in duration, especially when hunting the larger rorqual or baleen whales in the open ocean. Frequently an entire pod will surface and dive simultaneously, even when separated by broad expanses of water. The pod members will correlate abreast like advancing flanks of military troops marching n formation, rising and falling in perfect unison.
The acoustic repertoire of Killer Whales consists of pulsed calls and tonal sounds, called whistles. Although previous studies gave information on whistle parameters, no study has presented a detailed quantitative characterization of whistles from wild Killer Whales. Thus an interpretation of possible functions of whistles in Killer Whale underwater communication has been impossible so far. In this study acoustic parameters of whistles from groups of individually known Killer Whales were measured. Observations in the field indicate that whistles are close-range signals.
The majority of whistles (90%) were tones with several harmonics with the main energy concentrated in the fundamental. The remainders were tones with enhanced second or higher harmonics and tones without harmonics. Whistles had an average bandwidth of 4.5 kHz, an average dominant frequency of 8.3 kHz, and an average duration of 1.8 s. The number of frequency modulations per whistle ranged between 0 and 71. The study indicates that whistles in wild Killer Whales serve a different function than whistles of other delphinids. Their structure makes whistles of Killer Whales suitable to function as close-range motivational sounds.
Traveling along coastlines, females & juveniles tend to hold a steady course while the bulls investigate coves, inlets and beaches for potential food sources. This documented trait often sends swimmers & surfers scurrying for apparent safety with fear of a possible attack. Killer Whales have been observed attacking Pacific Walrus (Odobenus rosmarus) which sun themselves on rocks, floating ice blocks or on coastal sand bars. This unique predatory trait has been witnessed during such attacks on other oceanic marine mammals such as penguins & seals found resting on ice floes in both Arctic and Antarctic waters. This particular predatory trait frightens the intended prey so thoroughly, that they panic and dive directly into the water to escape the initial assault, only to be caught immediately into another Killer Whale’s path.
Field research has also shown that Killer Whales off the coasts of Argentina and Brazil have developed this predatory trait to an even higher form of predation. During the months of February through May, the southern hemispheric eastern population of Southern Sea Lions (Otaria flavescens) and Southern Elephant Seals (Mirounga leconina) come to these isolated beaches to give birth and to mate.
The infant pinnipeds begin to investigate the ocean at approximately 3-months of age, unknowing of the dangers that await their discovery of their new oceanic world. Killer Whales in this particular region of the world have become adept by surfing onto the beach front at low tide to prey upon the unsuspecting juvenile pinnipeds. Arriving like clockwork each year at this time, Killer Whales come to this area from their winter grounds in the Antarctic waters to prey upon the abundant food source and teach their young the art of predatory killing. This same form of hunting technique although not as dramatic but just as deadly, takes place on the isolated shores of the North American pacific rim region.
The transient population hunts unsuspecting Steller or Northern Sea Lions (Eumetopias jubatus) and the Northern Elephant Seal (Mirounga angustirostris) within the Baja peninsula region of California & Mexico, along the Pacific coastline of northern Vancouver Island and within Alaska’s vast Prince William Sound expanses. During such attacks, Killer Whales have been seen tossing a pinnipeds into the air repeatedly or simply holding the smaller mammal in their mouth, seeming to play with them. Researchers have theorized that such unique hunting techniques prove a learning facility for young juveniles. The adults have been seen, taking a still-living pinnipeds several miles away from shore and then releasing it for a young Killer Whale learning to use its sonar echolocation to locate an intended prey.
Little scientific information has been obtained regarding the extended distribution or various migratory patterns of Killer Whales. Although worldwide in predatory range, they tend to congregate in the world’s colder oceans, quiet possibly because a diversely more abundance of natural food sources can be located in these regions and the isolation from humans. Large concentrations of Killer Whales occur in several locations throughout the world’s oceans as in the Pacific Northwest rim off the coastlines of Alaska, British Columbia and Washington, where extensive field research has revealed that a large population of over 800 individuals inhabits this particular oceanic zone.
A known-resident population of over 300 individuals inhabits the waters of northern Washington’s Puget Sound and the vast Strait of Juan de Fuca, Georgia Strait, Johnstone Strait, Haro Strait and the Queen Charlotte Strait, which borders the coastlines of mainland British Columbia and Vancouver Island. Between 1979 and 1981, the “Moclips Cetological Society” conducted a “Killer Whale Survey” collecting 24 various sightings of Killer Whales off the coast of Vancouver Island’s “Inside Passage”. This particular body of water which separates Vancouver Island from mainland British Columbia until the early 1970’s, had never been considered abundant with Killer Whales.
A photo-identification field research project conducted by the “Pacific Biological Research Station” located in Nanimo, BC and headed by the facility’s Research Director Dr. Michael A. Bigg, led to the unique project development of a Photo-Identification Catalog displaying each individual Killer Whale and it’s corresponding pod membership.
Other regions of population concentration in large numbers exist near the continent of Antarctica, off the coastlines of Iceland & Greenland and off the southern coast of Australia. Only a few documented sightings of Killer Whales have ever come from the expansive Gulf of Mexico or the warm Caribbean Ocean region.
It is those regions of the world such as the Pacific Ocean rim basin of the North American continent where the colder waters contain a large population of pinnipeds, fish and migrating rorqual whales that Killer Whale sighting occur throughout the year.
A possible subspecies of “dwarf” or “yellow” Killer Whale was described from the ice edge in the Indian Ocean sector of the Antarctic from 60°E to 141°E. The skulls – especially the teeth – of the six specimens that were collected differ noticeably from those of most other Killer Whales. During the summer, at least, these small animals are said to range in the same waters as typical Killer Whales but not to mix in the same schools with the latter. The two kinds are also said to select different prey – fish as opposed to mammals, respectively. However, further studies are needed to ascertain whether these small whales deserve recognition as a separate species or subspecies.
KILLER WHALE (Wild) INTERACTION CASE STUDIES
In June 1983 while preparing to scuba dive within the Robson Bight Killer Whale sanctuary off the eastern Vancouver Island coastline, noted Marine Wildlife author Dr. Erich Hoyt came across a Killer Whale lying upside-down in just a few feet of water. As he waded towards what he believed to be the carcass of a dead animal, the 27’ bull rolled over and swam into deeper water. It is now suspected that the animal floated in this manner to “play dead” to entice prey such as waterfowl, seals or fish to draw near, but this particular predatory trait may serve to perform yet another life-cycle function within the mysterious world of the Killer Whale.
A team of British scientists in December 1955, were on an Antarctic research expedition and were given a rare opportunity to watch at extremely close range, a small pod of 7 Killer Whales that had become trapped in an icebound inlet. They were entrapped within the large oceanic inlet with 128 Beluga Whales (Delphinapterus leucas) and 4 Fin Whales (Balaenoptera physalus), having been cutoff from the open ocean by a quick change in temperature and ocean current. With an existing supply of available food, the Killer Whales appeared active and healthy. From time to time, individual Killer Whales would breach or raise their heads above the waterline known as “spy-hopping” and watch the scientists intently. One of the animals stuck its head out of the water at the edge of the ice pack and showed very little reaction as a research member poked at its snout with a ski pole. As strange as it may seem to people accustomed to believing Killer Whales as the highest degree of danger that a human being might encounter in the world’s oceans, the basic truth seems to support that the species often display a singular lack of aggressiveness towards humans.
Chief Dive Officer Dr. James R. Stewart of the “Scripps Institute of Oceanography” (now known as the “Sea World Research Institute”), has documented many encounters between humans & Killer Whales over the years. One such encounter occurred off California’s Pismo Beach in May 1955. During a dive session, divers Earl Murray & Conrad Linbough heard a low-pitched sound. Upon surfacing, they saw a female breach less than 50 yards from their surface position.
Off the coast of Mexico’s San Benitos Island in March 1959, a scuba diving team consisting of Dr. Patrick Cunnison, Emil Habecker, Dr. Wheeler North and Dr. Ronald Stewart, saw a mature bull patrolling a small inlet cove that contained some juvenile Northern Elephant Seals. After chasing the whale out of the inlet with their boat, Habecker remained on-board to stand watch while the remaining dive team members entered the water. A little more than 15 minutes into the dive, the submerged members heard rifle shots being fired from the surface. Quickly surfacing, the divers were astonished to find that the Killer Whale was once again at the rear of the inlet, having swum past them while they were submerged. In June 1960, a small pod consisting of 4 individuals approached a pair of divers in La Jolla Cove off the southern California coastline. A large bull came to within 21’ of the rest of the 18 member diving class.
Off the coastline of Cardiff in southern California in April 1967, Dr. North had another extremely close encounter. While on the bottom attempting to free an anchor that had become entangled in some rocks, he heard several low-level sounds. Upon surfacing, he saw a small female breach some 15’ away, look directly at him and then swim away. At the same time, 3 other individuals were within 50 yards of his position. Perhaps one of the closes accounts of a documented attack upon a human in the wild by a Killer Whale, took place off the coast of southern California near Pacific Grove on May 15, 1978.
In an article that appeared in “Skin Diver” magazine, approximately 200 people were onshore when they witnessed a Killer Whale swimming rapidly towards a group of 4 divers. As the divers floated on the surface some 150 yards off southern Vancouver Island’s Lover’s Point, the whale bumped into one of the individuals and sent him spinning. After the frightened divers scrambled on-board their vessel, the Killer Whale reportedly circled their craft for 20 minutes before finally departing.
Several other suspected attacks have been reported over the years and once such incident, appears to have unimpeachable evidence of a Killer Whale attacking a human in the wild. Off northern California’s Point Sur near the Monterey Bay coast, Hans Kretschmer was lying on his surfboard in about 100’ of water on September 9, 1972. He felt something nudge him from behind, looked over his shoulder and gave this account of what happened next.
“I saw a large glossy black object”, the 18-year old told Dr. James W. Hughes, a local Dentist who was part of the rescue team. “At first, I thought it was a large shark, then the animal grabbed me. I hit it on its head with my fist and thought for sure it would come after me again, but it swam off and I was able to swim back to shore.” To surgically close the 3 deep-gashes on Kretschmer’s left thigh required 143 stitches. Sheriff Deputies questioned a short time after the surgery, the teenager about the incident as were a close pair of Kretschmer’s friends.
According to Dr. Hughes, “the boys consistently described an animal that had a large dorsal fin, white markings on the underside of its body and was dark black on top”. Hughes himself an experienced diver and extremely familiar with various oceanic marine wildlife, stated without hesitation that “he was convinced from the young man’s detailed description, that the attacking animal had been a Killer Whale”.
Conclusive evidence of Kretschmer’s attacker came from the attending physician who performed the surgery. Dr. Charles R. Snorf in an extensive statement pronounced, “that the distance between the 3 deep-gashes corresponded to the exact distance found between a Killer Whale’s tooth pattern. Furthermore, the type of wounds inflicted were clean much like deep ax cuts and were just the sort of wounds that would have occurred in a resulting laceration administered by a Killer Whale.
Compared to the typical wounds inflicted by a Shark, both Seal and Sea Lion bites would have left canine-type tooth marks, which would have resulted in a ripping-type of injury display. On the other hand, a Shark would have inflicted a truly devastating wound, which would have resulted in the victim receiving an injury of completely torn-out chunks of large tissue and muscle. If it had been any type of Shark, his hand would have suffered severe abrasions due to a Shark’s extremely rough skin texture”.
That appears to be the only authenticated Killer Whale attack upon a human in the wild, although the noted attack did not result in a fatal injury. The whale probably realizing its mistake, simply left the area giving to the idea that the young man was not it’s intended prey. Steller Sea Lions which are on the prey list, had been observed in the immediate area just prior to the resulting attack.
Preliminary field data has also revealed that this oceanic marine mammal posses all of the human senses with the exception of smell. Essentially a sonic creature who apparently uses its sonar-echolocation capacities to navigate, hunt and communicate with others of its own kind, the case studies discussed thus far do not constitute concrete evidence that a Killer Whale will not attack a human. Current research suggest however, that this ultimate predator of the oceanic food chain may not be the terrible threat to swimmers and scuba divers that it has been reputed to be.
KILLER WHALE (Captive) INTERACTION CASE STUDIES
In captivity, several documented Killer Whale encounters including the ultimate death of a human, have been observed and even recorded on film.
During an afternoon “Whale Show” at Sea World of California in San Diego on April 21, 1979, trainer Annette Echis was riding on the back of a young Killer Whale stage-named “Shamu”. After the 20-year old fell off the whale’s back, “Shamu” turned and began to play “tug-of-war” with Echis’ leg as frantic training team members attempted to pull her leg free from the whale’s mouth. “Shamu” finally released her leg after a final quick tug and she was rushed to an area hospital. The leg wounds suffered by the young woman, required 3 hours of surgery and 177 stitches to close.
Other whales in various Sea Life parks have held their trainers underwater almost drowning them. Most of these rare incidents have happened when a trainer such as Echis, was riding a whale around the pool on its back and hanging onto its dorsal fin. Some of these captive Killer Whales may seem to tolerate these “back riding” performances, but it has been observed that most captive Killer Whales do not like this form of human interaction. Younger individuals new to captivity, frequently allow this type of performance but at an older stage of life, they become independent and rarely allow their handlers to climb onto their backs. Trainers still ride young captive Killer Whales at the Sea World facilities in Ohio, Florida, Texas and California, but the captive animals held in Canadian facilities such as the Vancouver Public Aquarium are no longer ridden. Killer Whales held in the Canadian venues, are viewed in constructed natural habitat settings rather than exploited for a “circus-type” atmosphere.
Several major incidents involving the death of a captive Killer Whale have taken place, especially in the various Sea World facilities. On June 2, 1989 during another typical “Whale Show” at San Diego’s Sea World, trainer Rick Emerson was riding a female Killer Whale stage-named “Kandu” around the main performance pool. Another whale stage-named “Shamu” was scheduled to jump over the trainer and “Kandu” as part of the performance. The show’s choreographer Dick Richardson displayed the wrong hand-signal jester to “Shamu” and instead of jumping over the other whale, instead landed directly on top of both “Kandu” & Emerson. The injured trainer suffered a sever concussion along with a collapsed lung and fractured rib cage and “Kandu” had to be euthanize. “Shamu” received minor lacerations, as several top executives & trainers were fired for the negative public relations event.
A compounded event took place once again at San Diego’s Sea World a few months later, this time involving a Killer Whale fight that led to yet another death of a captive animal. During a show on August 22, 1989, another whale stage-named “Kandu” died from massive bleeding caused by a freak injury. When showing “normal” Killer Whale behavior, she attacked a female stage-named “Corkey” who was attempting to dominate. Sea World veterinarian Dr. Jim McBain stated “that the 2.5 ton “Kandu” attacked the larger 3.5 ton “Corkey” during the facility’s 4:00 pm show”.
McBain continued, “the trainers saw the whales fighting in a holding pen behind the main pool access midway into the hour-long program. They reported seeing “Kandu” charge into “Corkey” with her mouth open. The impact of the whales fractured the smaller Killer Whale’s nasal passages”. The veterinarian said the there was nothing Sea World officials could do to save the smaller whale. As hundreds of spectators watched, “Kandu” spouted large amounts of blood, which stained the water and the sides of the tank. McBain further explained, “the altercation was initiated by the smaller whale. She was asserting her dominance by going after the larger whale with her mouth open. It’s very common behavior for the survival of any species, as the stronger animal has to rule. The death was an unexpected shock, but the altercation was not a rare event at all. It was normal Killer Whale behavior in the wild which was enviably displayed in a captive situation.”
Sea World officials briefly considered canceling the facility’s trademark “Whale Show”. But the suggestion was rejected when trainers argued that it would be better for the remaining whales to continue with a normal day. The scheduled shows continued throughout the day, though without any of the trainers in the presentation pool. The fatal collision between the pair of whales took only about 5 seconds, but “Kandu” lingered with life for about 45 minutes before she died. The expired female had made news in September of 1988, when she gave birth to a baby during a performance.
The birth was videotaped and Sea World’s multiple facilities have been using the tape within their advertising campaign entitled “the birth of Baby Shamu”. Despite the fact that the infant Killer Whale was still nursing, Sea World officials said they were extremely confident that “Kandu’s” death would not have an adverse effect upon the young whale.
McBain finished his statement by saying “the baby whale is feeding on approximately 40 to 45 pounds of solid food a day and is staying with “Corkey” at night. Obviously she realizes that something is completely different as the infant Killer Whale appears to be awaiting her mother’s return, but we think she’ll do all right at the final outcome. “Corkey” suffered superficial cuts and bruises, but was otherwise uninjured in the incident.”
At Oak Bay, British Columbia on February 22, 1991 at Sealand of the Pacific, the ultimate Killer Whale vs Human incident took place. During the small facility’s extensive “Whale Show”, a trio of Killer Whales dragged a 22-year old trainer to her death before hundreds of horrified spectators. Senior marine mammal trainer Keltie Lee Byrne fell into the water as she walked along the edge of the performance pool. As other training team members were assisting her out of the water, one of the whales grabbed her foot and pulled her back into the performance pool. The remaining pair of Killer Whales then proceeded to grab other portions of Byrne’s body and together, the trio of Killer Whales dragged the helpless trainer to the bottom of the pool before releasing her body.
Current scientific studies are underway which may lead to answers for such behavioral traits with captive Killer Whales. Most members of the scientific community believe that the enclosure of oceanic marine mammals who use a high degree of intelligence combined with their use of known sonar-echolocation, is severely restricted & depleted by the standard poured-cement walls of their enclosure tanks. A mundane existence from a captive Killer Whale’s normal day to day routine in the wild, may lead to a depletion of their normal mental state of mind as well. Scientists liken such mental stability theories to that of the known experiences of individuals held captive in “prisoner of war” camps during World War II and the Viet Nam conflict.
During a personal visit to Sea World of Florida in Orlando in May of 1984, the facility’s marine mammal research director Dr. Edward M. Asper showed me an aging bull that was kept in an observation tank away from the general public and was used strictly for observation and research. Dr. Asper explained that the large 26’ Killer Whale had killed several Bottlenose Dolphins (Tursiops truncates) and had even taken a grab at a woman who had gotten too close to his pool.
Dr. Asper jokingly informed me that there was a standing offer of $500.00 to anyone who would swim completely across the old whale’s tank. Needless to say, I declined Sea World’s generous offer. That very strange but true story ended however on August 11, 1985 when the old Killer Whale died.
Vancouver Aquarium commissioned 38-year-old sculptor, Samuel Burich to find and kill an Killer Whale and to fashion a life-sized model for the aquarium’s new British Columbia Hall. He set up a harpoon gun on Saturna Island in British Columbia’s Gulf Islands. Two months later, a pod of 13 Killer Whales approached the shore. Burich harpoons a young whale, injuring but not killing it. “Immediately, two pod members came to the aid of the stunned whale, pushing it to the surface to breathe. Then the whale seemed to come to life and struggled to free itself, jumping and smashing its tail and according to observers, uttering ‘shrill whistles so intense that they could easily be heard above the surface of the water 300 feet away.” Burich set off in a small boat to finish the job. He fired several rifle shells at the whale but the Killer Whale did not die.
The aquarium’s director Dr. Murray A. Newman, soon arrived from Vancouver by float plane and decided to try to save the 15-foot-long 1-ton whale. Using the line attached to the harpoon in its back, Burich and Bauer towed the whale to Vancouver. It took 16 hours through choppy seas and blinding squalls to drag the whale to Vancouver. “Moby Doll” is put into a makeshift pen at Burrard Dry docks and becomes an international celebrity and a magnet for scientists. The Royal Canadian Navy had recorded Killer Whales in 1956, but no scientific course of study was made of their sounds until “Moby Doll’s” capture.
Drs. William Schevill and William A. Watkins of Woods Hole Oceanographic Institute visit “Moby Doll” to study and record her sounds. Scientists and others who observe the whale comment on the whale’s docility, tameness. “The whale seemed to be suffering from shock. For a long time, “Moby Doll” would not eat. She was offered everything from salmon to horse hearts, but the whale only circled the pool night and day in a counterclockwise pattern.” After 55 days in captivity, “Moby Doll” begins eating up to 200 pounds of fish a day. But the whale has developed a skin disease from the low salinity of the harbor water, and continues to appear exhausted. The whale dies a month later, after 87 days in captivity. Newspapers around the world chronicle “Moby Doll’s” death. The Times of London gives the whale’s obituary a two-column heading, the same size given to the outbreak of World War II. “The widespread publicity, some of it the first positive press ever about Killer Whales, marked the beginning of an important change in the public attitude toward the species.” The necropsy revealed “Moby Doll” to be a male, not a female.
“Namu” was only the second Killer Whale captured and displayed in an aquarium exhibit and was the subject of a film that changed some people’s attitudes toward Killer Whales. In June 1965, William Lechkobit found a 22 foot male Killer Whale in his floating salmon net that had drifted close to shore near Namu, BC. The Killer Whale was sold for $8,000 to Edward “Ted” Griffin, a Seattle public aquarium owner but it ultimately cost Griffin $60,000 to transport the bull some 450 miles in a floating pen to Seattle.
“Namu” was an extremely popular attraction at the Seattle aquarium and Griffin soon captured a female to be a companion for “Namu”. The female whom Griffin named “Shamu”, did not get along with “Namu” however and “Shamu” was eventually leased to Sea World in San Diego. “Namu” survived one year in captivity and died in his pen on July 9, 1966. Although the young male Killer Whale “Moby Doll” was the first live Killer Whale exhibited in captivity, he survived less than 90 days in captivity. “Namu” was the first Killer Whale to survive in captivity long enough for a significant public exhibit. The United Artists film ”Namu, the Killer Whale” was released in 1966 and starred “Namu”, Robert Lansing and Lee Meriwether in a fictional story set in the San Juan Islands. The name “Namu” was also later used as a show-name for different Killer Whales in Sea World Adventure Parks shows.
Regardless of the documented events which have taken place in various captive situations, the Killer Whale is still considered the most formidable predator in all the world’s oceans. Combining strength with an extremely high degree of intelligence along with a swimming rate, which has been recorded of obtaining a top speed of 35 mph, this powerful oceanic marine mammal in the wild has no equal.
KILLER WHALE (Historic) INTERACTION CASE STUDIES
It might be argued that sharks as well, often approach humans without attacking but the comparison must end at that point. Each year, many reported and documented attacks by sharks occur, yet my research to this point has been able to uncover a single authenticated report of a Killer Whale fatally killing a human in the wild, which is not the case of the Elasmobranches, the family of sharks, rays and skates.
This scientific statement is especially significant when considering the fact that Killer Whales feed mainly on warm-bloodied animals and have been documented killing such animals in wholesale quantities. There have been many reports of Killer Whales smashing the sides of boats with their heads or tails. These are attacks in a very broad sense, but virtually all such incidents have occurred after an animal had been shot, harpooned or otherwise molested. Marine biological researchers have discovered that in most cases even with the strongest provocation, such retaliatory acts are indeed, extremely rare. One such incident however, occurred on March 11, 1952. It was one of some of the most widely reported attacks upon a vessel that perhaps, has ever been erroneously charged to a Killer Whale.
After a very large oceanic marine animal attacked a light sailing yacht off the coast of Los Angles puncturing the craft’s hull with its teeth, the pair of terrified occupants blamed the reported attack on a Killer Whale. The story was given credence by newspapers and even by a noted marine scientist. Photographs of the boat’s hull and careful examination of the crescent-shaped row of tooth marks on the vessel’s side however, strongly suggested that a very large shark had done the attack. Oceanic marine biologists on the inspection team believed after further study of the tooth patterns, that this attack had come from a Great White Shark (Carcharodon carcharias).
In another much published case that reportedly occurred on February 17, 1973 off the coastline of South Africa, a Killer Whale was reported to have sunk a boat and to have eaten 4 of the 6 occupants on-board. Upon further investigation however, marine biologist Dr. Joseph L. Smith of the I.W.C. (International Whaling Commission) stated that “the attacking animal was much too large to have been a Killer Whale and was probably either a Sperm Whale (Physeter macrocephalus) or a Blue Whale (Balaenoptera musculus) that perhaps believed that its calf was in some form of danger or quite simply, did not notice the vessel in its way.
It was a few days later that the missing individuals had died from drowning after discovering their bodies washed-up on an isolated South African beach near Cape Town. Upon medical examination of the bodies, there was found to be no form of evidence to support any claim that a Killer Whale had killed any of them.
One of the most widely quoted attacks by Killer Whales in the wild, took place during the 1911 “Terra Nova” expedition headed by Commander Robert F. Scott on the Antarctica continent. Scott’s research team had just tied-up their sled dogs on an adjacent ice floe on the outside of their campsite. The animals became very unsettled, as a pod of 11 Killer Whales appeared in the immediate area and occasionally stuck their heads up through the ice to take a look at the confined dogs. After the expedition’s chief photographer Ivan Ponting went out to the ice floe to film the whales, the Killer Whales quickly dove and disappeared. A few minutes passed, when the whales reappeared and began to smash the 5’ thick ice directly between the frightened dogs & Ponting. He ran from the ice floe as the whales repeatedly rammed their heads up through the frozen surface. After several minutes, the whales once again dove and disappeared from the scene. Whether or not the Killer Whales were trying to catch Ponting, the dogs or both will never be known. Even if the whales viewed the photographer as a prospective dinner, it is quite possible to ascertain that the Killer Whales simply mistook him and the dogs for either a seal or sea lion.
Popular literature is replete with the tales of Killer Whales attacking the largest members of the Cetacean family, the great baleen whales. Generally such attacks are made by an entire pod, usually numbering between 10 to 21 individuals working together much as a pack of wolves hunting a Caribou or Deer.
One such attack was filmed on October 14, 1979 by a scientific research team under the direction of the National Geographic Society who came upon an attack by 30 Killer Whales on a young 51’ Blue Whale (Balaenoptera musculus). On May 22, 1981, a group of marine biologists from the Hubbs/Sea World Research Institute photographed another such attack by 17 Killer Whales on an adult female 49’ Grey Whale (Eshrichtius robustus) off the Baja coast near San Diego, CA. Another dramatic opportunity to film the violence of a Killer Whale attack in the wild, came on May 12, 1992 as researchers came upon the attack of a female Grey Whale and her young calf off the coast of California’s Monterey Bay. The pod of 8 Killer Whales including 2 large bulls, completely devoured the infant whale and mortality wounded its mother, as she fled the bloody scene. Several adult male Grey Whales were in the immediate area, but did nothing to prevent the onslaught and simply stayed out of the killing zone.
The powerful jaws of a Killer Whale make little headway against the extremely thick layers of blubber found in a large adult rorqual whale. The tail flukes of these large whales can inflict tremendous damage or even mortally wound the smaller Killer Whale. Therefore, the Killer Whale usually prey upon the young, injured or aging baleen whale. Often after they have herded a pod of these larger rorqual animals into a panic-stricken group or after a baleen whale has been harpooned by commercial whalers, a few Killer Whales may hold onto the flukes while the remaining pod members force their heads in between the defenseless jaws of the intended prey. During a 1988 field study of Grey Whales, the Executive Curator of Marine Mammals for Sealand of the Pacific Dr. LeRoy S. Andrews found that 7 out of 35 whales within the study area off the coastline of southwestern Vancouver Island, had lost all or a significant portion of their tongues to attacks by Killer Whales.
The whaling industry too, has occasionally reported of the interactions of Killer Whales helping them to defeat and harvest the much larger baleen whales. In at least one region of the world, it has been claimed and written that Killer Whales aided measurably in the profitability of commercial whaling operations. Off the coast of New South Wales at Australia’s Twofold Bay, shore whaling was conducted for more than a century. It was at this location of the world, that Killer Whales are credited with many unique traits suggesting intentional cooperation with humans.
It has been reported in ancient whaling logs, as migrating Humpback Whales (Megaptera novaeangliae) or Southern Right Whales (Eubalaena australis) passed offshore, Killer Whales would swim to the Twofold Bay Whaling Station and attract the whaler’s attention by breaching and lob-tailing just offshore.
The whales would then lead the Twofold Bay Whaling fleet to their intended quarry while forcing the baleen whales into a herded circle by making pinpoint attacks upon the pod leaders. After a Humpback Whale or Southern Right Whale was harpooned, the Killer Whales helped to subdue it by leaping alternatively onto the baleen’s blowhole, thus hampering its breathing while other Killer Whales would swim under the massive body to prevent it from diving. As their reward for assisting in the hunt, the Killer Whales of Twofold Bay were allowed to eat the tongue before the whalers harvested the baleen whale. The whaling men of Twofold Bay recognized many of the Killer Whales by sight and even gave them names such as “Old Tom”, “Cooper” and “Hooker”, the latter so named because of its broken dorsal fin. The whaling men had the friendliest of feelings towards the Killer Whales of Twofold Bay and so tight was their bond with these oceanic marine predators, that it was a criminal offense within the region to ever harm one with a penalty for doing so, death by hanging. On those occasions when a chase boat capsized at sea, it was said that the Killer Whales often hovered near the swimming men until they could be rescued by another vessel.
The shore whaling activities ended at Twofold Bay in 1928. By then, most of the approximate 109 Killer Whales that had frequented this region for more than 70 yeas had either died or disappeared. One whale however, stayed around the Twofold Bay region until August of 1930, when he died and was found floating in the bay. The skeleton of “Old Tom” was preserved and is currently on display at the Eden Killer Whale Museum in Eden, NSW Australia.
Photograph of “Old Tom” with the Eden whalers
Skeleton of “Old Tom” at the Eden Killer Whale Museum
NORTHWEST PACIFIC FIELD RESEARCH DEVELOPMENT
To continue my inquiry into the ongoing research of the Killer Whale, the most probable region in the world would be the Pacific Northwest basin area of the North American continent. Thought by most marine biological researchers to contain one of the largest known populations of Killer Whales anywhere in the world’s oceans, it seems to be the most logical place to acquire current research and informational studies regarding these awesome oceanic marine mammals.
Killer Whales cruises the cold, plankton-rich waters of the Pacific Northwest during the entire year, from the southern coastline of Alaska’s Prince William Sound to as far south as the inlet waters of Seattle’s Puget Sound. Field research conducted has of yet, determined the exact population density within this vast region, though information & photographs secured by various ongoing field research stations and wildlife organizations currently estimate the number to be in access of well over 800 animals. Within this area, the social instincts of the species has been until recently, exploited for the purpose of capture and sale to public aquariums worldwide.
By firing a 16” harpoon into the back of a large adult cow presumably the pod’s matriarchal leader, a brightly colored float then trails from the harpoon and allows researchers to follow a pod for days. Ian McAskie and Dr. Michael A. Bigg were on one of these photo-identification research trips following a pod from their research vessel.
Within one of the many small natural inlets off the eastern coastline of British Columbia’s Vancouver Island, their boat was drifting quietly tailing a pod of 9 whales. McAskie started the boat’s engines to get closer to the animals when suddenly, 5 of the whales “spy-hopped” at the water’s surface some 140’ from their craft. The floatation device that was trailing the large cow, was found drifting just offshore 4 days later, some 16 miles from the original sighting.
Dr. David E. Caldwell of the University of Oregon’s Marine Mammal Biological staff summarized the care-giving behavior of Killer Whales during a field expedition conducted on April 22, 1980. A field research team in which he directed, came upon an injured female that was seen swimming beside her dead calf. The research team observed her circling the lifeless body for more than an hour until she too, eventually died. Even though local fishermen had shot both the female and her calf with rifle fire presumably, she never attacked the research vessel or displayed any signs of hostility toward the research team. She only continued throughout, to support her dead calf’s body during the short time she as well, remained alive.
Another strange episode regarding this type of Killer Whale behavior was recorded as a research team headed by Marineland of the Pacific’s Marine Mammal Research Director Dr. William L. Casey, captured a large female near Bellingham, WA on May 17, 1976. The rope, which had been thrown around her tail, became entangle in the ship’s propeller and Dr. Casey recounted the scene of the tragic accident that unfolded. “As the female Killer Whale struggled in the water, she emitted a series of low-level penetrating vocalizations. Within 20 minutes. the tail dorsal of her assumed companion male appeared. The bull closed in on the vessel’s hull at a high rate of speed, veering off only when he came extremely close to the boat’s hull. The animal then circled the rapped female slowly.
Within minutes, both whales then charged towards the boat, coming to within 5’ of the vessel. Charging once again, the pair struck the boat’s hull, sending the research members on-board sprawling onto the deck. The crew members grabbed their rifles and were forced to fire upon the animals and kill each in order to save the vessel and avoid any further damage to both the boat and quite possibly, to the individuals on-board”. This unfortunate capture incident was eventually translated into Dino de Laurentiis’ featured 1977 movie “Orca, the Killer Whale” starring Bo Derek, Charlotte Rampling, Keenan Winn, Richard Harris, Will Sampson and Robert Carradine and led to a continuing public outcry for the overall safety and scientific review of the various humane methods that were at that time, acceptable for the capturing and transporting techniques of Killer Whales and other small cetaceans.
The longest recorded time lapse for a Killer Whale to ever live in captivity to date is 18 years. The maximum life span of a Killer Whale in the wild as ascertained by current field research is on the average of 40-50 years for males and 70-90 years for females. Though these animals have tremendous recreational appeal, they are found to have no true commercial value, especially within the United States or Canada. In Asian waters however, Killer Whales are hunted for their fine clear oil, fresh meat for human consumption and for scrap meat used in fertilizer and fish bait.
The natural ability of some small cetaceans to communicate underwater was proven during the mid-1950’s by the Royal Canadian Navy’s Marine Research Center. Recorded vocalization and acoustical subsurface sounds among the Queen Charlotte Islands off the northern coast of mainland British Columbia and Vancouver Island during the summer of 1956 were analyzed. These studies found that the slowdown playback of the vocalization responses recorded by the Center’s Director of Research Dr. Wilson E. Schedvill of captured and cropped Killer Whales, were found to be individual clicks. These individual clicks when fast-repeated, resembled a human scream. The strident-scream and clicks are apparently used for communication and individual responses to other members of the species.
The separate clicks apparently determined echolocation readings or in simple terms, provides a “living” radar system that is used for an individual whale’s navigation. Some researchers believe that the failure of this echolocation system, may be a direct cause for Killer Whales as well as several other species of cetaceans, to run aground while navigating in shallow water. Among the hundreds of such recorded strandings, is the August 1965 mass death of 65 Killer Whales on an isolated New Zealand beach.
Sympathetic onlookers at the scene, tried to save a few of the whales by heading them back out to sea, only to have them simply turn back and die with their companions. Ongoing field research studies continue to ascertain a discovery answer for this puzzling phenomena and better understanding to perhaps assist in solving this perplexing problem.
POPULATION & PHOTO-IDENTIFICATION FIELD RESEARCH STUDIES
The scientific field research study of existing Killer Whale populations within the Northwest Pacific basin began in March 1972 and extending through the summer of September 1975. During this period of time, Canadian Oceanic Marine Biological researchers Graeme Ellis, Dr. John K.B. Ford, Ian McAskie and Photo-Identification Project Director Dr. Michael A. Bigg, correlated their expertise with Killer Whales and other small cetaceans to develop a standard photographic census technique program. Using various 35-mm cameras with telephoto lens and fast-film which provided basic information on population size and distribution, they compared individual Killer Whale profile “mug shots” and found they could identify an individual animal by its characteristic dorsal fin size and shape, the “saddle patch” region’s size and shape as well as both area’s distinguishing marks & scars. The photos were then cataloged with a corresponding letter by which was indicated a specific pod unit with a corresponding number which then referred to an individual whale within a certain pod.
Dr. Graeme Ellis, Dr. John K.B. Ford and Dr. Michael A. Bigg
During this 5-year Canadian study, various pods were photo-documented on 340 different encounters, ranging from southern Puget Sound to the extreme northern end of Vancouver Island. An overall account of 11,641 photographs, showed at least 20 different pods with individual numbers of approximately 210 individual whales. To enhance the Canadian information, further documentation of encounters within the northwest United States region of Puget Sound and the numerous San Juan islands, the Marine Mammal Division of the National Marine Fisheries Services contracted Kenneth Balcomb III, Research Director for the Moclips Cetological Society to conduct a similar field study within American waters.
Designating the unique project as the “Killer Whale Survey”, the Moclips Cetological Society began working directly with the Canadian researchers under the auspices of the University of Washington’s Marine Mammal Biology Center with experimental radio-tagging procedures of Killer Whales within the ever-expanding study area.
Using available media advertisements and the selling of public items such as posters & t-shirts, the “Killer Whale Survey” established a sighting network of interested citizens of both countries who would call a “Killer Whale 1-800” hotline whenever Killer Whales were spotted within the designated study region. Phone calls were accepted around the clock, with all sightings then relayed to field personnel who were prepared to respond in several small chase boats. When field staff encountered the sight Killer Whales, high-resolution 35-mm photographs of as many individual whales as possible were taken.
Using motorized Nikon cameras with 105-mm, 200-mm and 300-mm lenses, only black & white photos were taken instead of color, to prevent any possible shadows and to provide a clearer detailed image of the designated identification markings. Depending upon the existing daylight and time of day, Plus-X and Tri-X film was used. Some color work was accomplished however for various media informational release, using Kodachrome 25 & 64 film combined with high-speed Extachrome film.
The overall base objective of the survey, was to gather as much photographic information as possible, which would give a incise correlation of the current distribution, natural biological habitats, distinct social behavior and hopefully, the overall population dynamics of Killer Whales within the specified region of study.
During a selected 7-month study period in 1976 from April through October, 74 various encounters were made with 6 different pods totaling approximately 83 individual animals. Field personnel followed these various pods for 236 hours, as these encounters tracked over 750 nautical miles, averaging an approximate 3.2 knots per encounter speed. Nearly 700 sightings were received through phone calls from the general public and field personnel logged 13,641 nautical miles and over 1,396 hours in survey chase vessels. During this period of time, approximately 17,000 35-mm black & white photographs of individual whales within the study region were taken, studied and cataloged.
While there is still much to learn about the base-ecology of the Northwest Pacific population, a comprehensive understanding has been reached about the number of Killer Whales present. Through the combined efforts of the Canadian & United States research teams, a sizable block of information has been assembled and studied. The net results of 3 preliminary studies, has served as a baseline to direct future selected resource management decisions and to hopefully assist in conducting future correlating field research projects.
The basic Killer Whale social unit is known as a pod, which appears to be an extended genealogical family format, usually numbering from 5 to 20 individual members. About 20% of an average pod is composed of adult males. As a standard rule, for each bull there is 1 calf or juvenile member within a pod. The remaining 80% are either females or sub-adult females/males. A typically standard pod composition is an extremely cohesive unit with members usually traveling together within a few miles of each other, but most of the time even closer.
The known resident population of this particular region consists of 4 main pods totaling approximately 72 animals and are found throughout the Georgia Strait, Queen Charlotte Strait, Strait of Juan de Fuca, Johnstone Strait and the southern waters of Puget Sound. On extremely rare occasions, a combined mixture of resident pods intermingle for short intervals to form a “Super Pod” which can number from 47 to 138 whales.
Another sub-species of Killer Whale is found within the region and are known as transients. Their numbers have been systematically identified within 9 pods totaling approximately 58 individuals. These pods however, appear at irregular times of the year and do not associate with the region’s resident population.
NORTHWEST PACIFIC FIELD RESEARCH STUDIES
Early in the “Killer Whale Project”, researchers were puzzled by the fact that a few individual pod encounters had different behavioral patterns from the majority of the region’s population along with subtle differences in their appearance as well. These pods traveled in much smaller groups and were not as abundant during any time of the year. It was felt that these animals were perhaps, outcasts from larger groupings and were in transit to other possible locations. Researchers termed these smaller groups as “transients” and further field research has discovered that these particular animals are probably a separate race of Killer Whale, although the evolutionary relationship between residents and transients still remains a mystery. The most obvious distinguishing feature between residents & transients is their overall size and feeding behaviors. Resident pods contain from 5 to 20 members, whereas transient pods contain from 2 to 7 individuals. There are approximately 350 resident whales within the Northwest Pacific study region compared to approximately 80 transient whales.
Although pods of resident whales are seen during all months of the year, they are most common during May through October. Transient whales on the other hand, appear sporadically in about the same numbers throughout the year, especially during the later portions of August through October when juvenile Steller Sea Lions and Northern Elephant Seal pups begin to take to water combined with the annual migration patterns of the Grey Whales.
While this may lead to an apparent contradiction in terms, it is believed that existing terminology best describes the pair of races. Transients roam throughout a large range of up to 1,900 nautical miles along the coastlines and are rarely seen. Residents on the other hand, range only about 500 nautical miles along the coastlines and are frequently seen throughout an entire year, especially in April through October. It is not known to what extent of nautical mile range either race of Killer Whale travels off shore into the Pacific Ocean basin during the winter months from the Sea of Japan to the northern Arctic Ocean region.
The known Resident race has an established northern & southern community. The northern community’s range extends from mid-Vancouver Island north to the southeastern coast of Alaska. The range of the southern community extends from the southern most border of the northern community south into Puget Sound, around southern Vancouver Island and into the coastal Pacific Ocean basin of Grays Harbor, WA.
Each community’s pod population seems to travel throughout their known habitat range, but rarely enter into the known habitat range of the other. Transient pods seem to comprise a single community, which travels throughout both of the local community’s known southern coastal range of British Columbia and Washington to the Queen Charlotte Islands and as far north as the western coastal range of Alaska. Ongoing field research has never documented seeing resident & transient pods traveling together. Each distinct race of Killer Whale at various times of the year especially in August through October when vast schools of Salmon migrate to their inland rivers, sometimes pass to within 100 yards of each other, although researchers have yet to record any form of aggression or negative reaction between the pair of Killer Whale sub-species.
The known travel and dive patterns of the races also differ. Residents tend to travel along rather predictable coastal routes, generally from headland to headland. They rarely change directions abruptly unless in pursuit of prey or existing boat traffic. Transients enter small bays not normally visited by residents and often change travel directions suddenly, even when not foraging for a food source. Residents are recorded to have fairly routine dive patterns of 3 to 4 short dives of approximately 15 seconds in length. Transients at most times, have similar dive patters, although some dives last from 5 to 10 minutes in length due to their specialized diet of marine mammal prey. These differences, along with the smaller overall pod size, make transients much more difficult to locate and follow.
Another interesting difference is the variation in known dietary habits between Resident & Transient whales. Residents come inshore during the summer months to feed mainly on large schools of various fish, which aggregate within the narrow coastal “Inside Passage” of mainland British Columbia and Vancouver Island. There have been a few recorded instances of Resident’s preying upon an oceanic marine mammal, but this form of substance diet is probably not a common food source. Transient Killer Whales on the other hand, seem to seek various oceanic marine mammals including migrating baleen whales as their main source of diet. When their normal marine mammal prey is not available, fish may also be part of their dietary format.
The subspecies Killer Whale races also have vast differences in their known vocalization patterns, with the transients vocalizing far less frequently than residents due to the hearing ability of their form of food supply. The dialects of Transient pods contain a much smaller repertoire of perhaps 3 to 4 distinct communication calls whereas the Residents increase their multiple vocalization patterns to incorporate from perhaps 5 to 15 distinct communication patterns. The vocalization patterns of all transient pods within the Northwest Pacific basin region, share perhaps only 1 or 2 discerning commutation calls, none of which is produced or given recognition by any resident pod. Residents within this region, have exacting communication calls, which although similar to the human ear, have subtle recognizable differences by which individual resident pods are easily identified.
Current field observations conducted by the Marine Mammal Research Group’s Executive Director Dr. Robin W. Baird, have been made on the reactions of Steller or Northern Sea Lions and California Sea Lions (Zalophus californianus) to the presence of foraging transients. Alert and avoidance responses by the pinnipeds were made in the presence of Killer Whales of typical appearance. In the presence of a single animal, foraging Killer Whales of atypical appearance, no alert or avoidance response was ever observed. It is possible that the pinnipeds did not recognize the atypical whale as a Killer Whale, suggesting that the intended prey may posses a perceptual “search image” for the detection of predators based upon visual cues.
The innate ability of a predator to perceive cryptic prey using a perceptual “search image” has been previously documented. The thought-provoking concept of prey using a similar perceptual “search image” to detect potential predators, does not appear to have been previously documented. During an ongoing field research study of Killer Whale behavior and ecology being undertaken around southern Vancouver Island, certain interactions between transient Killer Whales, California and Stellar/Northern Sea Lions were noted on several occasions. These interactions suggest that pinnipeds may use a “search image” for the detection of potential predators. Observations of the interaction between transients and pennipeds were conducted during 1987 at the Race Rocks Ecological Reserve, an isolated archipelago of 9 small islands approximately 1 mile off the southernmost tip of British Columbia’s Vancouver Island in the Strait of Juan de Fuca.
The Race Rocks Ecological Reserve is a Pacific Harbor Seal (Phoca vitculina) year-round breeding colony, with seasonally abundant California and Steller/Northern Sea Lions. Vigilant behavior, high-speed swimming away from the transients, movement into dense Kelp beds and continuously lifting the upper body far out of the water have been observed.
A lone male Transient on October 12, 19897 of atypical appearance & photo-identified as X-10, was observed displaying this predatory trait. This individual whale has a dorsal fin, which is extremely bent over at its base to the left side with the upper half dragging in the water. He was observed surfacing 4 times within 3 meters of approximately 150 pinnipeds that were both in the water and hauled out on small reefs. The whale moved through narrow channels between several reefs and circled a reef on which pinnipeds were hauled out. No noticeable reaction by the pinnipeds was observed. It is possible that the intended prey did not recognize the atypical whale as a Killer Whale and might suggest, that pinnipeds respond to visual cues, such as the atypical dorsal fin on atypical Killer Whale, which match a perceptual “search image”.
Recognition of a predator’s behavioral state has been noted as an important factor in reaction to predators by terrestrial ungulates. From these observations, it is quite possible to ascertain that it is very unlikely the pinnipeds recognized X-10’s behavioral state since they did not react.
As the Killer Whales in an area may be members of more than an individual breeding population some of which specialize in feeding on fish, proximity of Killer Whales to other oceanic marine mammals may not always be perceived as a potential threat by the latter. Oceanic marine mammals have been reported in close proximity to Residents, showing no apparent reaction. Even in the presence of Residents however, pinnipeds may show interest with an increase in vigilant behavior. Killer Whale attacks upon oceanic marine mammals usually elicit a variety of escape responses.
Similar observations suggest that there may be a variety of cues influencing the reactions of oceanic marine mammals to Killer Whales. Further research on the perceptual processes pinnipeds and other similar prey species use to detect predators and on their ability to discriminate between potentially threatening Transients and non-threatening Residents is warranted.
In recent years, several reviews and original research papers dealing with seabird and marine mammal interactions have been published. Off the coast of Argentina, researchers recently described a parasitic relationship between Kelp Gulls (Larus dominicanus) and Southern Right Whales where the gulls regularly ate live flesh off the whale’s backs as they rested at the surface of the water. This feeding disrupted the normal behavior of the whales as many associations between whales, dolphins and seabirds occur because they are exploiting a common patch of food.
In these common circumstances, it has been noted that Humpback Whales have apparently accidentally ingested Cassin’s Auklets (Ptychoramphus aleuticus) while both species were feeding in close association at the same depth on large schools of Euphausids (Euphausia pacifica). In the Northwest Pacific region around southern Vancouver Island, various associations between seabirds and oceanic marine mammals take place.
When Transient Killer Whales are feeding on other oceanic marine mammals such as Pacific Harbor Seals or Northern Elephant Seals (Mirounga angustirostris), they often tear up the prey with many small pieces floating up to the water’s surface. The Glaucous-winged Gull (Larus glaucescens) and the Heermann’s Gull (Larus heermann), are among the many seabird species who regularly scavenge pieces of food off the surface of the water and even follow the whales for up to 20 minutes after a kill, apparently hoping for more food.
In some cases, the seabirds following the Transient Killer Whales could actually be detrimental to the whales, which use stealth and silence to capture pinnipeds. A flock of wheeling, crying Gulls might alert seals on or around rocks to the whale’s presence. Pinnipeds often bring their food especially larger fish, to the surface to eat and in the process of devouring them, often tear them up, attracting flocks of seabirds to scavenge on the pieces. This is an extremely common occurrence during the winter months around the Race Rocks Ecological Reserve area. Another type of predatory association between Killer Whales and seabirds is not quite as beneficial to the birds.
Several incidents of Killer Whales feeding on seabirds within the Northwest Pacific basin have been documented including a 1943 report of the consumption of a Brant Goose (Branta bernicla), a 1948 report of a feeding on White-winged Scooters (Melanitta fusca) off the coastline of Triple Island Lighthouse Station near Prince Rupert and documentation of a Black Cormorant (Phalacrocorax fucha) found in the stomach of a dead Transient identified as O-1, washed ashore in Boundary, BC in 1979. Although researchers have observed Resident Killer Whales considerably more often than Transients, Residents have never been observed attacking seabirds.
These attacks by Transients have had one thing in common however, the seabirds were all molting at the time and appeared unable to fly. One of these attacks involved an adult female identified as M-2. She surfaced towards a Rhinoceros Auklet (Cerorhinca monocerata) only to have the bird flap across the water and settle back down some 100 yards away. M-2 again surfaced nearly under it and continued to follow the seabird around in this manner for about a minute, white the rest of her pod continued to feed on a Northern Elephant Seal which had been killed earlier that afternoon. Anyone aware of the enormous size of this particular adult male pinnipeds specie would question the idea that perhaps there was not enough food already available for M-2. However in this case, the whale abandoned the chase and returned to the task of finishing off the seal.
Other recorded attacks have witnessed the resulting death of a Horned Grebe (Podiceps auritus) and an Eared Grebe (Podiceps migricollis), both attacks occurring in the vast Cordova Bay off the northern coastline of the Saanich peninsula. The seabirds were killed but not eaten, simply left floating on the water’s surface while the Killer Whales traveled on. An necropsy performed on the birds by the Pacific Biological Station’s Chief Oceanic Marine Mammal veterinarian Dr. Kenneth W. Langelier revealed no puncture wounds or broken bones, but showed that the seabird’s bodies were extremely bruised and both had died from trauma. The whales had “played” with the birds much in the same manner they often behave with pinnipeds.
The base reasons behind these unique attacks upon marine seabirds are yet unclear. The overall energetic intake from spending time capturing seabirds seems minimal. It could be a form of “play” behavior or it could function in teaching young whales.
Field observations were all conducted with adult animals and the behavior seems to be similar to “surplus or aggressive” killing. Another possibility is that at various times of the year, other forms of prey is less abundant or more difficult to catch and feeding on seabirds may be an important part of a Killer Whale’s diet supplement. Regardless of the underlying reasons for these interactions, they are obviously complex and may have an even more important consequence for all the species involved.
Finally, the overall physical appearance of Resident to Transient individuals differs in some very subtle features. The fin tip of the dorsal fin of Residents tends to be rounded and positioned over the rear insertion of the fin to the back. In a Transient identification, the dorsal fin is often pointed and positioned in the center between the front & rear insertions of the fin. The midpoint along the front edge of the dorsal on a Transient whale sometimes has a slight bulge. It is not always possible however, to distinguish the exact subspecies race of an individual on just the basis of a dorsal fin shape alone. The underlying fact that differences in appearance are found between these unique subspecies of Killer Whale suggest however, that they have been reproductively isolated for a very long period of time despite the known scientific research which has shown that they share much of the same environmental habitat.
It is suspected that they do not interbreed because of developed traditions against mixing as well as perhaps different feeding habits. This possible theory is widely accepted on the basis that these subspecies have unknowingly divided the natural food resources within the Northwest Pacific basin study area. The base prey selection and overall hunting traits for each race of Killer Whale, requires a much different type of strategy and this sole factor may have directly resulted in the development of the vast differences in social behavior and direct pod size.
NORTHWEST PACIFIC POPULATION STRUCTURE
Results of extensively conducted field studies by Canadian and United States research agencies, have confirmed that within the Northwest Pacific basin is found only 1 completely confined Residential pod of Killer Whales designated as the J-pod. This unique pod is always found within the Georgia Strait to the southern Puget Sound region. Its continual year-round wanderings at approximately 3 to 4 knots, brings J-pod to many bays, coastal passes and inlets of the lower Northwest Pacific Rim basin. J-pod is the most frequently seen pod of Killer Whales within this area, with almost 62% of all sightings reported. Being very tolerant of the region’s extensive boat traffic, some of the pod’s favorite routes of travel take it to within a few yards of the existing coastlines, near waterfront homes and into the midst of recreational and commercial shipping lanes.
A typical route itinerary for J-pod might be as follows: On the morning of the 1st day, the pod enters Puget Sound through the Admiralty Inlet. They move south throughout the day and arrive at Vashon Island late in the evening. J-pod spends their first night circumnavigating Vashon Island or perhaps, pushes farther south through the Tacoma Narrows into the lower southern region of Puget Sound. During the 2nd or 3rd day, the pod heads north into the Strait of Juan de Fuca toward Smith Island. By the 4th or 5th day, the pod is headed north into the Haro Strait, close to the western coastline of San Juan Island.
A couple of days traveling up the eastern coastline of Vancouver Island, brings J-pod into their northern most limitation and once again, the pod turns and heads south. Traveling via the eastern coastline of mainland British Columbia through the Georgia Strait, the J-pod returns back into United States waters and into the Rosario Strait by the 10th or 11th day, where the cycle begins once again.
Actual trackages show many variations in this travel itinerary, but this continual clockwise-cycle pattern seems to persist. J-pod offers a truly unique opportunity for marine biologists, researchers and the general public to study a segment of the Northwest Pacific region’s wild Killer Whale population as J-pod confine themselves to a vast 200-mile long, self-imposed natural aquarium.
The limited members of K-pod seem slightly less tolerant of human presence than those of J-pod. This pod often travels together with other whales of the L-pod, J-pod or both, making it rather difficult to identify each of the pod’s individual members. The pod’s large dominant bull K-1 however, is perhaps the most distinguishable Killer Whale in the entire Northwest Pacific region. K-1 displays a pair of notches on his upper rear margin of the dorsal fin that were placed by researchers on October 12, 1973 following his capture and subsequent release near Victoria, BC. K-pod spends part of its time on the western coast of Vancouver Island where its habits are little known.
Photograph of K-1 (deceased)
During any month of the year however, K-pod can be expected to travel to many of the inland coves and waterways mirroring a similar route as that of J-pod.
By far the largest assemblage of Killer Whales within the Northwest Pacific Rim basin, L-pod is less tolerant of human presence than either J or K-pods. They seem to travel somewhat faster than the other southern Resident pods and like K-pod, spend a great deal of time on the western Pacific Ocean side of Vancouver Island as well as in the Olympic Peninsula region of British Columbia. L-pod is the northern most Resident pod of the southern Resident community and is rarely seen traveling with either J or K-pods, except during the region’s annual salmon migration runs.
The smaller but more extensive pod population with makeup the northern community of Residents, travel in much the same manner as the southern community with the exception that their routes during the winter months take them far out into the open Pacific Ocean where researchers have yet to discover their patterns which perhaps takes them to as far as the northern Sea of Japan and into Alaska’s Bering Strait region. The northern community has been classified into a larger number of individual pods. Unlike the southern population, the smaller pods of the northern community infrequently come into direct contact with human or boat traffic due to the limited accessibility of the northern waters and small islands, which are channeled, between mainland British Columbia and Vancouver Island.
NORTHERN COMMUNITY RESIDENTY POPULATION CENSUS (1991)
|Base Pod /||Sub-Pod /||Females /||Males /||Juveniles|
SOUTHERN COMMUNITY RESIDENT POPULATION CENSUS (1991)
|Base Pod /||Sub-Pod /||Females /||Males /||Juveniles|
NORTHWEST PACIFIC TRANSIENT POPULATION CENSUS ( 1989, 1990 & 1991 )
|Base Pod /||Sub-Pod /||Females /||Males /||Juveniles|
UPDATED RESEARCH FINDING AND DISSERTATION SUMMARY
Based on photo-identification studies, numerous individual whales and/or pods have been documented to move between Puget Sound and southeastern Alaska; between southeastern Alaska and Prince William Sound; and between Prince William Sound and Kodiak Island. On the international level, whale movements from Alaska and British Columbia to California and from California to Mexico have been documented. In most geographical regions, Killer Whale movements may be related to movements of their prey and may travel as much as 125 – 200 km per day while foraging.
In the Beaufort, Chukchi and northern Bering Seas, Killer Whales move south with the advancing pack ice, performing long-range movements. Similar movements are reported for the western North Atlantic. Killer whales approach the Chukotka coasts in June and leave the area in November or even as late as December. On the other hand, year-round and seasonal occurrences are recorded for the waterways of British Columbia and Washington State, where pods are known to range approximately 370 nautical miles. Norwegian data indicate that Killer Whales occur in coastal waters all year-round, with concentrations in the Lofoten, More and Finnmark areas. However, Killer Whales present in offshore Norwegian waters appear to arrive there from Icelandic waters, following the migration of herring.
Studies that have photo identified Killer Whales around the Lofoten and Vesteralen islands of northern Norway during fall-winter (October-February) and summer (June-August) in 1986 and 1987. Based on a capture-recapture estimate, they determined that about 500 Killer Whales are present in these over wintering areas of the herring. Most of the whales leave the study area in January when herring migrate to the spawning grounds 700 km farther south. Based on the seasonal distribution, Killer Whale groups can be divided into three different types; whales present in fall-winter (25 groups), whales present both in fall and summer (12 groups) and whales present in summer (six groups). Most of the positions were received from the wintering grounds of herring.
However, five of the tagged whales made long distance movements away from this area; the swimming and diving behavior of the whales as well as information on prey items suggests that the function of these trips was to survey areas where herring is abundant during other seasons than winter. Based on photo identification data collected since 1987 the range of Killer Whales during October-January had been estimated to be 13 583 km² (estimated as a minimum convex polygon). The satellite tracking study expanded the known range of Killer Whales during this season considerably. The ranges varied between the individuals; the smallest estimated Kernel home range was 3566 km² (95 % isopleths) and the largest 288 284 km² (95 % isopleths).
In Northern Patagonia the seasonal distribution of Killer Whales is correlated to the distribution of Southern Sea Lions and Elephant Seals. Most encounters with the whales at Punta Norte occurred in December and March-May, during the pennipeds breeding cycle. Whales depart the area in May when pennipeds migrate to winter rookeries. One pod, Patagonia Norte B (PNB) was photographed in Golfo San Jose on 9 January 1986 and in Punta Norte 1 day later, some 60 km apart.
Evidence of seasonality is also observed in the southern part of the northeastern Atlantic. In the southern hemisphere, Killer Whales are found in warm waters in winter and migrate into high latitudes in the summer. This migration appears to be related to the migration of prey species, in particular the Minke Whale (Balaenoptera acutorostrata). However, reported sighting Killer Whales in Antarctic sea ice in August, i.e. in late winter, indicating that some individuals may be resident year-round.
Transient whales appear to cover a more extensive range than residents. A distance of over 2600 km (California to Alaska) has been reported for a transient group and field photographed three individuals in Monterey Bay, California, that had previously been identified off Alaska.
Killer Whales have been exploited at low levels in several regions worldwide. Norwegian whalers in the eastern North Atlantic took an average of 56 whales per year from 1938 to 1981. The Japanese took an average of 43 whales per year along their coastal waters from 1946 to 1981. The Soviets, whaling primarily in the Antarctic, took an average of 26 animals annually from 1935 to 1979, but took 916 animals in the 1979/80 Antarctic seasons. After 1976, Iceland has been involved in live-captures of Killer Whales for export. During the period 1976-1988, 59 whales were collected, of which 8 were released, 3 died and 48 (an average 3.7 per year) were exported. In 1991, the Icelandic government announced that once current permits for live capture expire, no new ones would be issued. Live-captures of Killer Whales have also taken place in Japanese waters. Incidental takes during fishing operations occur, but are considered rare.
Fishermen in many areas see Killer Whales as competitors and shooting of whales is known to occur. This problem is especially serious in Alaska, where conflicts with long line fisheries occur. Although much reduced, some such persecution continues today.
High levels of PCB and DDT (250 ppm and 640 ppm, respectively) were reported in the blubber of an adult male transient killer whale in Washington State and 38 ppm PCB and 59 ppm DDE wet weight levels in a resident mature bull. Issued reports that total PCB concentrations were surprisingly high in three killer whales communities (2 resident and 1 transient population) frequenting the coastal waters of British Columbia, Canada.
Transient Killer Whales were particularly contaminated. Toxic Equivalents in most Killer Whales sampled, easily surpassed adverse effects levels established for Harbor Seals, suggesting that the majority of free-ranging Killer Whales in this region are at risk for toxic effects. The southern resident and transient Killer Whales of British Columbia can be considered among the most contaminated cetaceans in the world.
Habitat disturbance may be a matter for concern in areas inhabited by killer whales and supporting whale-watching industries reports on propeller scars observed on Killer Whales and their possible causes of mortality. Moving boats can also interfere with natural activities and resting, and underwater boat noise can affect social and echolocation signals of the whales or otherwise interfere with foraging.
These effects are likely to be cumulative and may result in displacement or reduced fitness and death. From a sound propagation and impact model deduced that fast boats are audible to Killer Whales over 16 km, mask Killer Whale calls over 14 km, elicit a behavioral response over 200 m, and cause a temporary threshold shift (TTS) in hearing of 5 dB after 30-50 min within 450 m. For boats cruising at slow speeds, the predicted ranges were 1 km for audibility and masking, 50 m for behavioral responses, and 20 m for TTS. Superposed noise levels of a number of boats circulating around or following the whales were close to the critical level assumed to cause a permanent hearing loss over prolonged exposure. From a 1988 study on the effects of acoustic harassment devices, it deduced that whale displacement resulted from the deliberate introduction of noise into their environment. Another 1988 study investigated whether the current guidelines for whale watchers are sufficient to minimize disturbance to northern resident Killer Whales in Johnstone Strait. Local guidelines request that boaters approach whales no closer than 100m.
Additionally, boaters are requested not to speed up when close to whales in order to place their boat in a whale’s predicted path: a practice known as ‘leapfrogging’, find that leapfrogging is a disruptive style of whale watching, and should be discouraged: as the experimental boat increased speed to overtake the whale’s path, the source level of engine noise increased by 14dB. Assuming a standard spherical transmission loss model, the fast-moving boat would need to be 500m from the whale for the received sound level to be the same as that received from a slow-moving boat at 100m. Whale watching guidelines should therefore encourage boaters to slow down around whales, and not to resume full speed while whales are within 500m.
The Exxon Valdez oil spill in Alaska was strongly correlated with the subsequent loss of 14 whales from a pod that had been seen swimming through light oil slicks early in the spill. Oil spills may also have an indirect effect by reducing prey abundance. Although in general opportunistic feeders, some populations of Killer Whales could be affected by reduction of their food supply. For example, coastal Norwegian populations reportedly feed mainly upon herring, a fish heavily exploited in the area. In Alaska, anthropogenic effects on the ecosystem have been made responsible for Killer Whale predation on Sea Otters and associated ecological implication. In British Columbia and Washington, Salmon stocks have significantly declined as an effect of over fishing, habitat degradation and reduced ocean survival. This is likely to affect fish-eating resident Killer Whale populations in that area.
For the Southern Indian Ocean, the strong decline reported for the coastal waters of Possession Island between 1988 and 2000 may be attributed to several factors: a low and decreasing fecundity, possibly impacted by a density dependence (Allee effect); the decline of the main preys: large baleen whales due to past whaling, and southern Elephant Seals from the 1970 to 1990 which remained in low numbers up to 1997 at least; the possible mortality induced by recent interactions with the Patagonian Tooth Fish (Dissostichus eleginoides) long line fishery; and iv) the possible dispersion of individuals or groups from the coastal waters. A few individuals were observed with poorly known “offshore” Killer Whales interacting with long liners, but presently, there is no evidence of mixing with surrounding Killer Whale concentrations in Prince Edward Islands, South Africa or Antarctic. A preliminary toxicological study indicates that PCBs levels are considerably lower than in British Columbia transients, however the burdens are not negligible and the effects of PCBs on health at the observed concentrations are unknown. We fear that the Killer Whales of Possession Island might disappear with unique genetic diversity and social culture, like AT-1 transients in Alaska.
ICELANDIC & NORWEGIAN FIELD RESEARCH STUDIES
Between October 10th & November 20th of 1986, various ship surveys were conducted off the southern and eastern coasts of Iceland to photographically identify Killer Whales. These activities represented the second successive year of a research program to assess population size & structure, social organization, movements and acoustic behavior of the region’s Killer Whale population. Field research data from this study period, was supplemented by a sample of photographs taken incidentally in 1981 and 1984. During the 1986 field season, a total of 37 photographic observations of Killer Whales including 23 which resulted in the photo-identification of 143 individuals.
Of the 143 known individual animals, 4 had been previously photo-identified in 1984, 22 in 1985 and 3 in both years. Current research now records a total of 143 individuals having been identified & cataloged in the region’s population form photographs taken since 1981. The 143 animals consist of 41 (29%) adult males, 83 (58%) adult females or sub-adult males/females and 19 (13%) juveniles or calves. Of the animals identified, 61 were listed in the 1986 study with 79 individuals having already been provisionally cataloged into a classified 6 pod units. The remaining animals have been cataloged as miscellaneous Transients, pending collection of further research field data on their individual social associations.
Distinguishing marks on most of the 143 photo-identified animals, can confidently be regarded as stable enough to be useful in the identification of select individuals in future encounters. The longevity however, of distinguishing features of some animals (39 of 84 whales first identified in 1986 and 63 of the 143 total) is less certain. The region’s population ranges over at least 43 nautical miles within the study areas of 1985, extending to a range of 87 nautical miles in 19866. Thus far, there has been no direct identification matches with the 26 individual Killer Whales photo-identified off the coastline of Norway since 1983. In Iceland, the species has never been the subject of any form of organized fishery, although sporadic takes by the Icelandic Fishing Industry in 1917 and 1926 are recorded. Norwegian small-type whales in Icelandic waters between 1955 and 1972 however, made fishery catches.
Resulting complaints by the region’s fishermen that extremely large numbers of Killer Whales were not only eating the vast shoals of fish, but also damaging fishing gear were recorded. These reports eventually led to the U.S. Navy being contracted in October of 1956, to rid the coastal areas of Killer Whales by sporadic “target practice” by their planes and ships. Reports on the results of this project were contradicting, saying either that not very many animals were killed or that hundreds of animals were destroyed.
During the past 15 years, the only direct take of Killer Whales in Icelandic or Norwegian waters has been those taken in a limited live-capture fishery which began in 1976 to furnish worldwide marine wildlife parks.
Although these oceanic marine mammals are frequent visitors to both Icelandic and Norwegian coastal waters during the fall & winter, very limited information until recently, has been made available on the biological structure and overall numbers of the species. Various scientific field reports have listed a minimum estimate of 284 animals within the near shore Atlantic Herring (Clupea harengus) fishing grounds in 1982, based upon coordinated census from the region’s fishing fleets. During the summer of 1986, an aerial survey conducted in Icelandic coastal waters located 6 sightings of 14 whales all around the country while no Killer Whales were observed in an equivalent survey conducted in 1987 in the same field location.
In contrast however, there were 23 sightings (21 primary) of 175 Killer Whales (155 primary) during the 1987 summer season (shipboard surveys) conducted simultaneously from 3 contracted Icelandic sighting vessels operating within the Icelandic & Norwegian coastal waters. The whales were widely distributed around Iceland & Norway as most sightings were made approximately 40 to 100 nautical miles east of Iceland. From these field sightings, it was estimated that there were 6,847 Killer Whales within the study area surveyed by the project vessels, with a 95% lower limit of around 4,000 animals. The estimate for the larger region including sightings made on-board various Faeroese sighting vessels was 8,272 animals, with a coefficient of 0.32 variations.
A long-term study was initiated in 1985 to determine the following aspects of the biology and behavior of Killer Whales off Iceland with respect to their population size & structure, vital rates, population status & identity, social organization & behavior, movement patterns and acoustical behavior. A brief pilot study reported that Killer Whales had been photographed and their vocalizations recorded off the Icelandic eastern coast in 1985.
Following the base-procedures now solidly established for studying this species, principal investigators used high resolution black & white photographs, supplemented by other existing available research information, to identify specific individuals, determine their approximate age & sex and assign each provisionally to the pod classification to which they appeared to belong.
Approximately 1,050 photographic frames from this 1985 field research study were analyzed. These photos were supplemented by photographs of Killer Whales, which were taken off Iceland incidental to other conducted research duties in 1981 (53 frames) and 1984 (487 frames). This latter sampling included photographs of varying format, film type and quality. From the material available over the period, a total of 57 whales (11 from 1981 and 1984 combined and 46 from 1985), were photo-identified and assigned to one of the three existing pods. Photographic and acoustical field research on Killer Whales around Iceland was continued through 1986.
To identify individual Killer Whales, the photographic negatives were examined using a Wild M5 Stereo Dissection Microscope with 8 power eyepieces, affording 4.8 to 40.0-power magnification, although 9.6 power was used most commonly. Whenever possible, identified animals were provisionally assigned to a specific pod based upon associations among individuals detected within the photographic material. Each individual pod was designated by a letter code (a.k.a. “I” for Iceland, followed by A.B.C., etc.) assigned sequentially as individual pods were cataloged. Within each designated pod, individual whales were sequentially numbered (a.k.a. “IB-7” indicates the 7th animal identified in the Icelandic Pod “B”). In cases where an identified individual could not be assigned to a particular pod, the animal was given a different type of number or letter designation and included in a miscellaneous category pending collection of further field data.
A 12.7 x 17.8 cm glossy print was made from the best image of each animal and placed into a working catalog. This catalog is now updated annually and will be published once it is thought to contain a substantial proportion of known Killer Whales within the Icelandic population. The identified individuals were also provisionally assigned to one of the 3 following broad age/sex categories: 1) Adult Males; 2) Adult Females & Sub-Adult Males; 3) Calves or Juveniles.
“Orcinus orca” Killer Whale Eco-types & Forms
Dr. Michael A. Bigg’s newly-discovered Killer Whale photo-identification system
Studying the unique habits of Killer Whales in the wild, requires a great amount of effort and extreme patience. Information accumulates very slowly and requires field data input from a vast amount of different sources. With a little practice, boaters who find themselves in the midst of Killer Whales should be able to recognize what pod or multiple pods are present with the help of currently published photo-documentation material.
While the assistance of boaters and interested individuals onshore in taking photographs and reporting various sightings is greatly appreciated by marine biologists and researchers, it should be kept in mind that it is illegal to harass or pursue any oceanic marine mammal. If an individual is in a vessel and wishes to observe or photograph Killer Whales, it must be done at an extremely slow speed and at a respectful distance.
These animals like any other wild species, will be much more tolerant if followed from the rear or towards the side and never directly in their immediate path of travel.
Is the chasing and capture of Killer Whales in the open ocean legal, ethical or humane? Since 1965, various worldwide private aquarium personnel have admittedly killed 173 Killer Whales during capture operations. Harpoons, bullets or sein-net entanglements have quietly killed many other whales. All were legally destroyed under since outdated laws. No laws until very recently, protected the small cetaceans of the world’s oceans.
Should humans have the right to harass or maim wild oceanic marine mammals, which belong to all the world’s citizens? The highly integrated social behavior and intelligence possessed by Killer Whales, will allow them to eventually learn through experiences, sensitized by the bloodshed of their species and thus, avoid regions of known danger. Must we all lose the right as well as the thrill of seeing these magnificent oceanic marine mammals roaming free, unaltered and at rare moments, approachable because various individuals and corporations seek profit or fame?
Upon the completion of this paper, I continue to firmly support the need for continued field research and vast amounts of scientific studies yet to be done not only with Killer Whales, but with the many varied oceanic species that are in real danger of losing their base population as well as their freedom.
It is hoped that ongoing field research will continue from organizations and learned individuals with timely assistance from the general public. It is after all, the vast multitude of human population that shares this planet called Earth with the Killer Whale and its relatives. The opportunity to view all species of marine & land-based wildlife at close quarters within their natural environmental habitat depends solely upon the continued scientific support of such natural habitat, food sources and the overall lifestyle, which will be foremost if Mankind is to maintain integrity with their population status.
A friend to Mankind? An intelligent oceanic marine animal whose knowledge of the world’s oceans may someday benefit Mankind?
There is much that can be learned from this remarkable aquatic animal and from the world in which it lives. Accurate field research studies on this until now, little known and much maligned marine mammal will undoubtedly reveal a tremendous amount of surprisingly new information in the years to come.
I suggest first, that all oceanic marine mammals especially small cetaceans taken for exhibition, be captured in regions remote from their normal population base. Secondly, those oceanic marine mammals including small cetaceans not currently protected by law, be classified as “game animals” and thus, be drawn into a form of wildlife management program. This change would not be equivalent to classifying them as “sport animals” however.
Agencies such as selected State & Providential departments, are the only type of legal authorities equipped to regulate the hunting and capture of such animals. A “game permit” status system like that of the United States, Mexico and Canada, would insure that responsible officials would be present during such chasing & handling of small cetaceans. Up to now, these types of capture operations have been well hidden under a political “smoke screen” of selected trade secrecy. Responsible supervision would extend to the care of captured small cetaceans as well as focus upon their needed attention regarding their captivity conditions and individual medical care.
I have longed marveled and seen with awe, the beautiful Killer Whale and the oceanic world in which it lives. Power, grace, intelligence and rare beauty are the only superlatives by which to best describe this magnificent oceanic marine mammal. There is no creature within the world’s oceans that can rival a Killer Whale for true wonder and sheer excitement. A friend to Mankind? We as humans are the only species who control this animal’s destiny and the remarkable Killer Whale has only to await the answer.
Until 16 years ago, our scientific knowledge of the natural history of this much-maligned species was solely base upon scattered observations and fabled anecdotes. Today, the scientific community has complied a vast comprehensive understanding of the many varied aspects of its distribution, population dynamics, social & internal organization, unique feeding characteristics and overall behavior patterns.
We are extremely fortunate to have the Pacific Northwest basin as the only known area in which Killer Whales can predictably be found in such abundance and in such accessible locations. This region of the world has become internationally known as the best area by which to observe these unique oceanic marine mammals living in the wild. With such an important natural resource available, we must do all that we can to ensure that their natural wildlife habitat remains undisturbed.
It is now known that Killer Whales can deal with a certain amount of disruption in their environment, but just how much they will tolerate remains unknown at this time. Disturbances within their natural environmental habitat can be created by a variety of methods, through overextended exploitation of available fish stocks, by the industrialization of coastal waterways regularly used by the whales or even by well-mannered individuals who inadvertently disrupt a pod while in pursuit of a snapshot. Growing public awareness and concern for Killer Whales and other small cetaceans will hopefully, serve to minimize the overall impact of human interference and encroachment into the natural environment of this unique oceanic marine species.
As one of the best known and perhaps, most intensively studied populations of cetaceans in the world, past and current field research has already provided much of the base data needed for an effective wildlife management of the species. There is still much more to learn however, especially in the areas of social behavior and communication among Killer Whales.
With further coordinated field research studies, the scientific community will undoubtedly broaden its understanding of these fascinating oceanic marine mammals in orchestration with continued public interest and concern.
Hopefully, these factors will combine to create an environment in which both Mankind and the Killer Whale can live in harmony and prosper in the world’s oceans for decades to come.
Upon clinical acceptance of this paper, research staff positions will be accepted with the Asociacion Delphys of Argentina and the Cetacean Specialist Group of India together with a listing in the prestigious “United Nation’s Directory of Marine Mammal Specialists”.
This paper is dedicated to the lasting memory of my mentor Dr. Michael A. Bigg and honors his internationally acclaimed work with Killer Whales. His vast personal expertise and personal interest together with his true friendship, directed my career in an untold measure that I will always be forever grateful. He shared his time & untold knowledge by which a unique and lasting correlation truly benefited my knowledge and understanding of the Marine Biological Sciences as well as my independent Killer Whale research. Dr. Bigg’s memory will always be an enormous part of my overall scientific research, career and personal life for which I can never repay.
My deepest appreciation to Dr. Erich Hoyt for his cherished friendship, which enabled me to grow within the field of the Marine Biological Sciences and acquire a true understanding and appreciation for the beauty that has always surrounded me.
A joyful acknowledgment to Don Sineti and his group “the Morgan’s” for their music that surrounded my unceasing research studies with a unique tranquility.
An expression of sincere gratitude to the many learned associates within the worldwide scientific community, who greatly assisted by making my studies possible and for freely sharing their extensive scientific knowledge, timely suggestions, materials and wisdom.
A heartfelt acknowledgment of appreciation is hereby extended as well, to the administration & staff personnel of the John G. Shedd Aquarium, the National Aquarium of New Zealand, the Vancouver Public Aquarium, the Taronga Zoo and the Monterey Bay Aquarium.
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