Wednesday, February 20, 2008

Horn Shark


The horn shark (also known as the Californian horn shark) gets its name because it has a short, blunt head with high ridges above the eyes. They range in size from approximately 97 cm to 120 cm (around 3 feet long from the tip of the tail to the nose). They are a brownish color covered in black spots and their underbellies have a yellowish tint.

Horn sharks live in rocky reefs and kelp forests although while juvenile, many often stay in open sandy waters. They can be found from central California to the Sea of Cortex and possibly South America in depths that range from 2 to 150 meters.

Adults tend to return to the same resting spot every day. Horn sharks hide in crevices or caves during the day and venture out at night. They nocturnally hunt for urchins, crabs, worms, anemones, and bony fish. 

These sharks are oviparous. That means that they lay egg cases. The horn shark has a distinctive auger shaped egg case with 2 threadlike filaments extending from one end. The egg will typically hatch in 7 to 9 months. They are kelp colored however sometimes they detach from the branch they were wrapped around and many float up and wash onto beach shores.

Horn sharks are not graceful swimmers and sometimes use their strong pectoral fins to crawl along rocks. The teeth lining the front of the horn shark's jaws are sharp and used for grasping prey; while the teeth in the back are flat (molar-like) which is useful for crushing shellfish. The common name 'horn" refers to the spines in front of each dorsal fin (they have 2) that are their main defense against bigger fish (and sharks) that try to swallow them.

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