Picture yourself like any free-swimming squid, thousands of feet underwater in the ethereal silence of the freezing-cold deep sea. In the crushing pressure and near-absolute black void, something is moving towards you slowly, but steadily. Its streamlined bulk, soft pink body, and blue-tipped fins are capped off by an almost comically long snout that overhangs an underslung mouth.
Though that mouth’s many needle-like teeth and the creature’s twelve-foot length are enough to put any snack-sized cephalopod of the deep on edge, the pointy-nosed behemoth isn’t coming right towards you and seems to not even notice your camouflaged presence. Until, once it comes closer, it slowly turns your way, as if seeing right through your natural stealth. Primed for escape, you start to try and jet as fast as possible in the opposite direction. But before you can even move a tentacle, that funny-looking underslung mouth shoots forwards with a speed that can barely be believed, and you’re engulfed, gone.
You’ve just had a brief and terrifying introduction to one of the deep sea’s most unique top predators: the goblin shark. If that introduction has you looking for a flight to the furthest possible location from the ocean, worry not—there have been zero recorded fatal goblin shark attacks on humans. While they can grow to some impressive sizes, with males reaching maturity at roughly 8.5 feet long and observed specimens reaching lengths up to 20 feet, goblin sharks inhabit a world utterly alien and inhospitable to humans. Spending most of their lives in all three major oceans over the upper continental slope in depths ranging from 800 to over 3000 ft (the benthopelagic zone), these snaggletoothed hunters live so deep that even our basic observations of them are severely limited.
Life in the Slow Lane
While human encounters with goblin sharks may be few and far between, what we do know about them has made one thing pretty clear—far from an athletic and speedy predator like a great white or mako shark (their relatives in the order Lanmiformes, or mackerel sharks), goblin sharks live seemingly mellow lives. Though they rarely swim at more than a very sluggish pace, this is actually a behavior perfectly suited to maximize their survival and effectiveness as deep-water predators. Given the deep ocean’s freezing temperatures and relatively sparse amount of high-energy food compared to shallower depths, anything as large as a goblin shark has to prioritize wasting as little energy as possible between its meals.
With that in mind, living life as a slow-moving ambush predator that saves its energy for a lightning-fast strike to secure a meal makes perfect sense! While their more famous relatives might be flashier, goblin sharks are an absolutely ancient species perfectly suited to their environment and lifestyle. In fact, these sharks are the only living species of their family Mitsukurinidae—a lineage going back 125 million years! You don’t survive for that long by being wasteful.
What’s In a Name?
With its protruding jaw, flabby body, and absolute unit of a nose, it’s clear how the goblin shark acquired its fantastical and monstrous moniker. However, those looks aren’t just meant to ingrain themselves in the nightmares of their prey—like everything that lives in the punishing environment of the deep sea, their bodies are adapted to waste as little energy as possible while they move about in search of their next meal.
Let’s start with that snout. Goblin sharks possess numerous tiny pores in their skin, each of which is part of an organ called an ampule of Lorenzini. These remarkable organs are electroreceptors, able to sense the minute changes in electrical fields surrounding the shark when other living organisms (emitting their own electricity from their nervous system’s activity) get close enough. Though all sharks possess these ampulae, goblin sharks have a particularly high density of them concentrated on their nose. In the darkness of the waters where they usually swim, this highly developed electrosensing allows goblin sharks to locate with pinpoint accuracy prey that might be totally invisible— using nothing more than the prey’s own heartbeat! Though their eyes aren’t always useful in the darkness that often surrounds goblin sharks, their ability to contract their pupils seems to indicate that they get some good use out of their vision.
That said, finding prey is only part of the equation. Once their sensitive snout or eyes helps them find a potential meal, the goblin shark slowly closes the distance until it can use its secret weapon—its jaws! Lined with rows of thin and pointed teeth (perfect for gripping the soft bodies common among their prey species like squids and rat-tail fishes), goblin sharks have the terrifying ability to literally sling their entire jawbone forward, massive extending the forward range of their bite. Ligaments attached to the joint of their jawbone are held with constant tension in normal circumstances, acting like rubber bands that catapult the whole jaw forward at a speed unmatched by any other animals on earth!
Simultaneously, a tongue-likecalled a basihyal on the floor of their mouth drops down, expanding the size of their mouth and sucking in water as the jaw rockets out. While many other sharks are able to extend their jaws to some degree when feeding, goblin sharks stand out from the crowd and can protrude their jaw anywhere from 2-9 times further than other species. Given their slow lifestyle and poor high-speed swimming abilities, this uniquely adapted feeding behavior likely helps them catch agile prey that would otherwise escape once they close to biting distance. Look up some videos of them feeding in action to see something awesomely creepy!
Finally, goblin sharks possess a body shape and composition that is (surprise!) perfectly suited to their lifestyle. Though they lack a swim bladder to adjust their buoyancy manually, goblin sharks (like many deep-sea sharks) have muscle and liver tissue that contains abnormally high levels of very low-density fatty acids. This low density allows them to maintain nearly perfect neutral buoyancy with zero extra effort, allowing them to save as much energy as possible. Their low-angled tails with elongated caudal fins supplement this by optimizing their forward thrust when swimming with long, slow motions. When you aren’t sure when you’ll find your next meal, preserving as much energy as possible (and having the tools to seal the deal in the blink of an eye) is the name of the game!
International Shark of Mystery
Despite the spooky name and less-than-friendly face when jaws are extended, it’s important to remember that, like all sharks, goblin sharks are important predators within their ecosystem. In fact, our startlingly low knowledge of goblins and many other deep-sea sharks means that we might be doing far more harm to them than we even know. The majority of goblin sharks studied by humans have been caught as bycatch in commercial fishing, and plenty of people may not even know that they exist. So, tell your friends, keep your eyes on the deep, and go enjoy all the fish—from friendly to frightful!
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