Fast Facts: Crested Hornsharks

  • The Crested Horn Shark is often confused with the more common Port Jackson Shark, because they look similar. A way to tell them apart is to look for the different banded pattern.
  • Males mature at about 60 cm in length. Females mature at about 70 cm.
  • The Crested Hornshark is endemic to Australia, occurring from southern Queensland to southern New South Wales.
  • They are usually solitary animals, though, they have been occasionally spotted in groups.
  • Within Sydney, I’ve personally seen more Port Jackson Sharks, than Crested Horn Sharks.
  • You can find them under ledges, or out in the open.
  • They have been observed eating the eggs of Port Jackson Sharks.
  • They are found from shallow inshore waters, down to depths of around 90 m, feeding off echinoderms, crustaceans, molluscs and small fishes.
  • They have a blunt head, with a prominent ridge above both eyes.
  • They have two tall dorsal fins.
  • The species is grey to brown with large dark blotches.
  • The male sharks have a pair of external claspers that they insert into the cloaca – the female’s reproductive organs.
  • It is an egg-laying (oviparous) species.
  • In July and August, females lay dark brown spiralled egg cases that are usually seen attached by tendrils to seaweed. The egg cases of Port Jackson Sharks look similar but, lack tendrils.
  • When the Port Jackson shark lays an egg, she’ll pick it up in her mouth and screw it into rocks and crevices to anchor it, so that they don’t wash away and that’s what gives them that shape.
  • The purpose of the tendrils on the eggs from the Crested Horn Shark, are so the egg becomes tangled in seaweed, or other surfaces, which enables the egg to be anchored.
  • Young Crested Hornsharks hatch from the egg case after about eight months and are about 22 cm in length.
  • Once the sharks lay their eggs, the pups are completely on their own, subject to the weather and other predators. When they emerge, they have to be ready to go, able to feed and able to look after themselves, because we haven’t seen any evidence that the parents provide care post laying eggs.
  • And life isn’t easy inside the egg, either. There is some work that suggests embryos in shark eggs reduce their activity when predators are present to reduce chances of predation. 
  • Crested Horn sharks are docile, gentle and beautiful creatures which are such a pleasure to see.

References: Own personal experience, https://australian.museum, australiangeographic.com.au and “Diving with Sharks” by Nigel Marsh and Andy Murch.

Published by Karina Teuma

karinateuma.com Karina Teuma is a Passionate Marine Biology Enthusiast, Environmentalist, Snorkeller, Freediver, Scuba Diver and more.

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