Thursday, July 25th 2019, 4:09 pm - They may not be too cuddly, but there's a lot to like about the ocean's most famous predator.
July 28 marks the beginning of Shark Week, and to celebrate, we decided to take a good look at some of the sea's most unfairly maligned denizens: Sharks.
Though an apex predator, they're much less dangerous to humans than the popular imagination would suggest, and there are some kinds that are just gorgeous.
With all eyes on the waves, we did a little research, and came up with these eight kinds of unusual, weird and wonderful sharks.
THE EPAULETTE SHARK SORT-OF FIGURED OUT HOW TO WALK
Meet the epaulette shark. Also known as “the shark that walks.”
Epaulette shark (Hemiscyllium ocellatum) on a beach in Port Tribulation, Queensland. Source: Wikimedia Commons.
Now, no need to start relocating to the mountains or raising your houses on stilts or anything just yet: It uses those thick fins to navigate the ocean bottom and coral reefs, in a semi-walking motion rather than the graceful, ominous swimming common among others of their kind.
They often find themselves temporarily trapped in very shallow pools left by the receding tide, where they are easily captured by humans (apparently, they’re mostly harmless, although a bit nippy).
What really sets epaulettes apart from other sharks is the fact they can survive on very little oxygen for hours at a time, even in the warm, 30-degree water of those tidal pools we mentioned.
It does this by shutting down non-essential brain functions and lowering its life-signs to the point where it can endure low oxygen levels with no ill effects.
No word on whether it’s ever been spotted dragging itself OUT of those pools and across dry land – but scientists are interested in epaulettes as potential links in the chain from full-aquatic animals, to land-based vertebrates.
It’s fortunate that it’s so harmless, then, given it’s the one type of shark ever likely to crawl out of the sea to nibble on sunbathers' toes.
SAWSHARKS KIND OF LOOK LIKE LUMBERJACK EQUIPMENT
“Okay, come on now!” the first person to stumble upon one of these beasties might well have yelled at Evolution. “It looks like you took a regular shark, stuck a chainsaw on the end of its nose, and called it a day. This can’t be a real thing. You’re totally messing with us.”
In all fairness, the sawshark kind of does look like the result of asking an eight-year-old how he would make sharks even cooler.
The prominent schnozz that gives the shark its name is used to take down prey, disabling it with a rapid side-to-side motion, featuring “teeth” of alternating size.
It also features a pair of barbells halfway down the snout, which it uses to detect its prey, mostly fish, crustaceans and shrimp.
Like almost all sharks, it's pretty much harmless to humans, and in fact are often confused with sawfish, a similar-looking creature that doesn’t have those barbells, can grow much larger and is actually a kind of ray rather than a shark.
They’d be happy at the distinction. Even though they share the same fearsome features, saw sharks are doing mostly all right, but many species of sawfish are critically endangered.
BASKING SHARKS COULD SWALLOW YOU IN ONE GULP (BUT COULDN'T EAT YOU IF THEY TRIED)
And here’s another shark that fits the pattern of looking like it lives in your nightmares, despite being quite, quite harmless.
In fact, the basking shark couldn't eat you if it wanted to. It’s a filter feeder, with a car-sized mouth lined not with row upon horrible row of sharp teeth, but with a set of strainers.
It filters plankton and krill out of the water just by roaming the oceans with its 1.2-metre mouth hanging wide open. It seems they can actually filter a cubic kilometre of water every hour.
We picked this one because it has that impressive maw, even though it’s not actually the largest fish in the sea. That would be the whale shark:
That one can get up to 12 metres in length. And even though, like the basking shark, it is also totally harmless, we still aren’t super keen on the idea of a 12-metre-long shark.
THE GOBLIN SHARK'S UGLINESS IS ACTUALLY A SUPERPOWER
At first glance, the goblin shark looks like another beast that proves beyond a doubt that Evolution has a bit of a mean streak sometimes.
Look at that silly nose. And those jaws! Hanging open like that, all slack-jawed and goofy. Even its flesh is pale and pasty, apparently slightly loose and pudgy. How did this ever qualify as an apex predator?
Well, see this?
Yeah. It's only slack-jawed when it's dead or in full-on feeding mode. And when it’s the latter, it whips its jaw right out of its mouth like a catapult, snagging prey with one bite.
Regardless of what you see in the video above, it isn't remotely considered a threat to humans, despite occasionally growing larger than 3 m. You almost never find it in the shallows, and when humans encounter it, it’s as bycatch in nets cast hundreds of metres down, where the goblin sharks live.
That depth is a clue as to why it looks so ridiculous. That nose is packed with electroreceptors that help it detect prey in low light environments.
Image: Hussakof L. A new goblin shark, Scapanorhynchus jordani, from Japan. Bulletin of the AMNH 26, 257-262. Source: Wikimedia Commons.
And that pale, fleshy skin? In the dark depths of the ocean, it has no need of camouflage. Its prey usually can’t see it’s coming anyway.
So, yeah, goofy looking. But down there, in the sunless abyss, no one is laughing.
GREENLAND SHARKS LIVE FOR CENTURIES
Greenland sharks are known for having voracious and varied appetites. Everything from fish and dolphins, to seals, polar bears, horses and reindeer have been found in its belly over the centuries (in 2013, one had to be rescued while nearly choking on a moose antler).
Close up image of a greenland shark taken at the floe edge of the Admiralty Inlet, Nunavut. Source: Hemming1952/Wikipedia Commons.
It apparently doesn't turn its nose up at a certain species of land-dwelling bipedal mammals. At least one was found with a human leg inside it, and a wildlife officer in the St. Lawrence estuary reported being stalked across the ice by one in 1940.
So does that mean there’s seriously a horde of sharks hanging around off Newfoundland ready to pounce on literally anything that ventures too near the shore?
Not even slightly. The reality is, the Greenland shark is probably an opportunistic predator that moonlights as a scavenger, a theory based on the fact it swims VERY slowly and is practically blind.
The icy waters off of Canada, Greenland and Iceland are its main home - already an oddity, because it lives quite comfortably in waters near-zero degrees, sometimes thousands of metres down, making it the northern-most known shark species. Here's one spotted deep below the waters of Admiralty Inlet on northern Baffin Island.