They do that because they're not feeding in the mid-water column like most sharks, on other fishes and things, rather, they're crawling around, poking their heads under coral heads and into the seagrass, looking for molluscs and crustaceans, which is what they typically eat, and they have crushing teeth as opposed to sharp teeth. They're little, typically not more than 75 centimetres in length, and they walk across the bottom of the sea floor. So it throws its jaws out of its sockets and grabs the prey and swallows it whole.Įpaulette Sharks are one of my favourite sharks, and that's probably because they're the least shark-like of any shark, at least in terms of how we normally think of them. Of the two specimens we have, one specimen has its jaws naturally set and the other one, we've set the jaws out, which is how the fish catches prey. So what you can see here - see the liquid coming out - they're the extra pores that can pick up electricity underwater. And one of the things about sharks is that they have an extra sense. The Goblin Sharks are a deep sea shark, so 1000 to 2000 meters. We have two adults and two juveniles in here. And these large, oily livers sort of provide them with that neutral buoyancy that they need to sort of basically hover and not waste too much energy having to swim around all the time. And inside this cavity they have a very enlarged liver which contains what's called squalene oil. So one feature of these dogfish sharks is that actually have a very long abdominal cavity. And a lot of a lot of what we know about hydrodynamics for engineering purposes has actually come from the design of the water flow over shark denticles. One other interesting thing with a lot of these deep water species that actually have quite rough denticles on the body, which is what you see is a scale on a fish, in sharks that have these really reduced scales called denticles, and they assist with sort of hydrodynamic flow. A lot of these dog sharks will feed on mid-water fish, bony fish or fish occurring on the bottom. This is used as a form of protection against predators. They actually can have very bright green eyes when they're first brought up, but they lose that colouration very quickly.īut like a lot of dogfish species, they have these large spines in front of the dorsal fins. But this is an example of the sort of colouration you might expect in quite a deep dwelling shark, sort of occurring below 600 meters where there's no light penetrating you get quite dark bodies. As you can see it's quite a dark colour but when they're caught fresh some of them tend to have a bit of a golden sort of sheen on them, which is where the common name comes from. So this species is called the Golden Dogfish. And they always have two and as they grow larger they calcify, which essentially they get like a hard calcified skeleton within them, which is how you can actually determine whether the animal is mature. So the clasper is a modified part of the pelvic fin, which is what the males use - it's a sexual organ of the males. It doesn't have the normal situation around here that you'd see in other sharks. Most sharks have two dorsal fins, they've just got the single one, which is situated a long way back, almost creating that sort of paddle, which essentially is used to create that swimming motion that they'd have. And in the water, they actually swim by undulating the whole body like an eel would. They're the only shark that has this sort of really elongate body shape. But what's impressive with these is these teeth that they have, these three cusps of similar size, but they actually have almost like a quite a prehistoric look.īut they've evolved this eel like body. From that you can tell that they would live in quite low oxygen environments. It looks like a very frilly sort of head shape. It got its name from essentially these really enlarged gill slits that sort of joined here. The Frill Shark is one of my favourite deep water sharks.
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