I used to think goblin sharks were just weird-looking loners drifting around in the deep ocean, minding their own business.
Turns out, we have almost no idea if that’s true. Here’s the thing: goblin sharks—those alien-looking creatures with the extendable jaws and the bizarre pink skin—live at depths between 270 and 960 meters, sometimes deeper, and we’ve only ever caught them by accident. Fishermen haul them up in trawl nets, dead or dying, and that’s pretty much our entire data set. We don’t have footage of them interacting with each other. We don’t know if they hunt in groups, if they have territories, if they’re fiercely solitary or surprisingly social. The scientific literature on Mitsukurina owstoni is embarrassingly thin, which means any discussion of their social structure is basically educated guessing layered on top of what we know about other deep-sea sharks, and even that isn’t much. It’s frustrating, honestly, because these animals have been around for roughly 125 million years, give or take, and we’re still fumbling in the dark.
Why Deep-Sea Observation Technology Keeps Letting Us Down in This Case
The problem is straightforward but maddeningly difficult to solve. Goblin sharks live in an environment that destroys most equipment we send down there. The pressure is immense—around 100 atmospheres at 1,000 meters—and it’s pitch black except for bioluminescence. ROVs (remotely operated vehicles) can handle the pressure, sure, but they’re expensive, slow, and loud, and goblin sharks are rare enough that you could search for months without spotting one. Tagging them is nearly impossible because they usually don’t survive being brought to the surface, and even if they did, the tags we use for other sharks often fail at those depths. Wait—maybe that’s changing. Some newer acoustic tags are rated for deeper dives, but we’d still need to recieve a signal, and the ocean down there doesn’t exactly cooperate with our transmission technology.
What We Can Infer from Their Jaw Structure and Prey Preferences
Goblin sharks have those infamous protrusible jaws that shoot forward to grab prey, which suggests they’re ambush predators. Their diet seems to include teleost fish, squid, and crustaceans, based on stomach content analysis from the few specimens we’ve examined. If they’re ambush hunters, that might mean they’re solitary—many ambush predators are, because coordinating attacks in the dark is hard and prey is scarce enough that sharing doesn’t make sense. But here’s where it gets messy: some deep-sea species that we assumed were solitary turned out to aggregate around food sources or during mating season. We’ve seen this with sixgill sharks and certain deep-sea octopuses. So maybe goblin sharks do the same thing, gathering in small groups when conditions are right, then dispersing. Or maybe they’re territorial. Or maybe they’re genuinely solitary their entire lives except for mating. We just don’t know.
The Mating Mystery and Why It Matters for Understanding Their Social Behavior
Nobody has ever observed goblin shark mating.
That single fact encapsulates the entire problem. We’ve found pregnant females, so we know they reproduce, and we think they’re ovoviviparous—the eggs hatch inside the mother—but that’s about it. Do males compete for females? Do they have courtship displays? Do they migrate to specific breeding grounds, and if so, does that create temporary social structures? Other shark species show remarkable complexity during mating season—some form dominance hierarchies, others engage in elaborate pre-mating rituals. If goblin sharks do anything similar, it would completely change how we understand their social organization, but right now it’s all speculation. I guess it makes sense that we’d be in the dark about this, given how rarely we encounter them alive, but it’s still definately one of the most glaring gaps in marine biology. Anyway, until we develop better deep-sea monitoring technology or get extraordinarily lucky with submersible footage, the social structure of goblin shark populations remains one of those humbling reminders that the ocean still holds secrets we can’t crack.
