Port Jackson Bullhead Shark (Heterodontus portusjacksoni)

Sometimes I really wish animals actually looked like what they were called. Today’s animal, the Port Jackson bullhead shark, is one of those. Don’t you think it would be awesome if these guys were actually part shark, part bull? I picture all the sleek streamlined-ness of a shark with a bull’s head – or more accurately, a bull’s horns. That would be a formidable beast. Still, even if the bullhead shark isn’t quite the way I picture it, it’s still a neat animal.

Bullhead sharks are part of the family Heterodontidae, which is composed of only nine living species. The Port Jackson shark lives in the waters around southern Australia. As you might have guessed, it’s named after Port Jackson in Sydney Harbour. They are bottom-dwelling sharks, living in rocky areas of up to 275 meters deep.

A port Jackson shark with an egg case in its mouth. The sharks lay egg cases in the form of a double helix.  Photo credit: Jayne Jenkins

A port Jackson shark with an egg case in its mouth. The sharks lay egg cases in the form of a double helix.
Photo credit: Jayne Jenkins

The Port Jackson shark is the largest of the bullhead sharks, reaching up to 1.67 meters. They are grey or light brown, with black markings on the face and on their bodies. These markings give the shark the appearance of wearing a harness – wouldn’t it be fun to actually hitch sharks up to some kind of watercraft and have them pull you around? Surely some villain in some movie has done this. Otherwise I will be seriously upset with the movie industry.

A lovely shot of the shark's face, showing the strange teeth it has, as well as the nostrils which give the shark the name 'bullhead'.  Image source: http://www.reddit.com/r/sharks/comments/1pxxkb/a_very_strange_shark_xpost_from_rwtf/

A lovely shot of the shark’s face, showing the strange teeth it has, as well as the nostrils which give the shark the name ‘bullhead’.
Image source: http://www.reddit.com/r/sharks/comments/1pxxkb/a_very_strange_shark_xpost_from_rwtf/

Port Jackson sharks have very specialized sets of teeth – the front teeth are sharp and pointed, while the back teeth are flat. The teeth help the shark eat its prey, which consists of molluscs and crustaceans. The front teeth are used to grab and break the shells of the prey, and the back teeth are used to crush and grind up the shells. The shark has another unusual adaptation to help with feeding. Unlike most sharks, which have to keep moving to keep water flowing over their gills so they can breathe, the Port Jackson shark has a system that pumps water over the gills. This allows the shark to sit peacefully while munching away on some tasty shellfish. Of course, ingesting a whole bunch of shells often leads to a lot of unwanted stuff in the shark’s belly, so the shark can turn its stomach inside out and spit it out of their mouths. Pretty gross, if you ask me.

All in all, the Port Jackson bullhead shark is a pretty strange beast. Luckily for them, these sharks are not a food source for people, and are not a threat to humans. Which means they’ve been largely left alone, so they are not endangered. I still think it would be neat if they had horns growing out of their skulls, but I guess one animal can’t have everything.

Cover image source: http://www.theage.com.au/victoria/shark-attack-shock-just-a-case-of-fish-n-nips-20111020-1m8oe.html

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