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the Legacy continues…………………….
Gregory R. Mann, Ph.D. {ret.}

Horn Shark

“Heterodontus francisci”

Horn Sharks have short, blunt heads with high ridges above their eyes and large fin spines including 2 prominent dorsal fin spines hence their name. They are small and quite beautiful sharks reaching about 1.22 meters in length. These sharks are a sluggish, solitary species with broad, strong fins used to maneuver over the ocean bottom in search of prey. Growing to a length of 0.57 meters, they are also most active at night and feed heavily on crabs. This species is often observed resting on ledges of vertical rock faces at depths of 15-30 meters. Despite their defensive dorsal spines, one small specimen was found in the stomach of a Tiger Shark. Horn Sharks are found in subtropical waters between 37°N-22°N, 124°W-75°W including: the eastern Pacific in central California to the Gulf of California and likely south to Ecuador & Peru.

Horn Sharks prefer rocky bottoms, kelp beds, sand flats, deep crevices, small caves and underwater caverns. Adults tend to maintain the same resting places day-to-day. They feed mainly on small fishes and invertebrates. They are nocturnal animals coming out from under ledges & rocks at night to feed. Horn Sharks are oviparous, meaning females release eggs with a yolk sac attached. Horn Sharks mate in the months of December and January. The male Horn Shark chases the female until the latter is ready, then both drop to the ocean bottom. The male grabs the female’s pectoral fin with his teeth and inserts a single clasper in her cloaca; copulation lasts 30-40 minutes. A few weeks after copulation, the female will deposit the fertilized eggs in cases among the rocks where they will hatch anywhere from 6-9 months later. The young sharks when first-born, are roughly 15-17 centimeters in length. Horn Sharks may bite fingers when harassed and their large fin spines can cause nasty puncture wounds.

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