What Kills A Killer Whale? Meet The Animals That (Almost) Can’t Be Killed

In 2017, epic footage from a helicopter showed a saltwater crocodile carrying a freshwater crocodile in its mouth like a carrot stick. Freshwater crocodiles are proficient hunters themselves, but they’re dwarfed by the might of one of Earth’s apex predators – aka, an animal with no natural predators.

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The saltwater crocodile, making light lunch of the croc, gets to enjoy the top spot on the food chain. It's a privileged position, but as they say, with great power comes great responsibility. 

What are apex predators?

Apex predators are animals that sit at the top of their food chain. If you can cast your mind back to biology class, those webs used to kick off with the producers (often plants that can make their own food) that were then eaten by the next layer, who get eaten by the next layer, and so on and so forth until you reach the apex predators – kings and queens of their castles.

The club is small, but powerful, and being a member doesn’t necessarily guarantee you a long life. After all, even a lion is an easy target when it’s just a cub, but let that cub grow into 375 kilograms (826 pounds) of muscle, teeth, and claws, and you’re looking at an indomitable opponent. 

This all, of course, comes with the unfortunate caveat that we humans and our technology have disrupted the order of things somewhat. Many of Earth's apex predators are threatened due to human activity, but remove poaching, habitat degradation, and climate change from the equation (if only we could), and some of these behemoths would be unstoppable.

So, by land, sea, or air – let’s meet some of Earth’s apex predators.

Saltwater crocodiles

The largest reptile alive on Earth today is the saltwater crocodile. One croc called Lolong was among the record breakers, captured in 2011. At 6.17 meters (20 feet and 3 inches) from snout to tail, it became the largest crocodile ever caught, measured, and placed in captivity, and serves as a hefty reminder of why killing these things is so difficult.

At such enormous sizes and armed with a mouthful of daggers for teeth, it’s hardly surprising that they are apex predators within their ecosystem, but are they unkillable? Not quite.

In 2024, a known saltwater crocodile called Dominator put on quite the show for a boat of tourists when it killed a 3-meter (9.8 feet) saltwater crocodile in front of them. According to 9News, the attack largely took place underwater until Dominator emerged with the other croc’s leg in its mouth. Gnarly.

Lions

Known as the king of the jungle with good reason, lions occupy the highest trophic level as one of Earth’s most impressive apex predators. It's not just about blood and guts, though. Oh no, their top spot means they are a vital keystone species for ensuring healthy ecosystems.

Perhaps their most obvious ecosystem service is that they balance out predator and prey populations by occasionally killing them (okay, some blood and guts). It’s easy enough to picture why you don’t want too many jackals hunting on the savannah, but even herbivorous prey animals can be damaging in large numbers due to the impact they have as they graze in the environment.

Then, there’s the work they do for the underdogs. A lion won’t strip a carcass clean, so when it’s done, the little guys get to have their fun. This creates nutrient-rich hotspots that feed scavengers, nourish soils, and support vegetation.

A lion’s life is a dangerous one, however, and while non-human animals actively hunting them is relatively unheard of, they do sometimes die from injuries sustained while trying to take down large or dangerous prey. Their biggest threat, other than other lions, is humans due to poaching and habitat loss.

Tigers

Tigers are the biggest of the big cats and they too curl up comfortably at the top of the food chain. As The Big Cat Sanctuary writes, “As apex predators, tigers don’t have any natural predators. However, they are at risk from human hunting and can be vulnerable to larger predators as cubs”. 

In case you’re wondering, “well hang about – what about those lions?” Though you'd think based on size, the tiger might win, the lion vs tiger debate won't be settled any time soon because their natural territories don’t overlap.

Though they may be safe from the other king of the jungle, tigers haven’t been having a very good time of it lately. They’ve lost almost 96 percent of their numbers since 1900, with habitat degradation, genetic isolation, and poaching threatening the species’ survival. The effect of diminishing populations is starting to show up in their coats, too. Just look at the pseudo-melanistic tigers in India’s Simipal Tiger Reserve that have become black cats with orange stripes, or the rarest tiger morph: golden tigers.

Bald eagles

Bald eagles are another apex predator that have no known natural predators other than humans. They are opportunistic hunters that will swoop down on prey, including fish, birds, reptiles, and mammals (in short, pretty much anything), as well as scavenging carcasses.

Things have been getting trickier for bald eagles in recent years, as though their numbers have been increasing, available resources have been decreasing. That said, a happy association was identified between bald eagles and dairy farmers – two groups that historically have been in conflict with one another – as it found farmers were happy to have eagles around because they could predate pest species and scavenge cow afterbirth. Win-win!

Pretty powerful, those eagles, which is what makes it extra embarrassing that this one got beaked through the heart by a loon.

Polar bears

Polar bears are the largest land predators on the planet, so it figures that nobody’s really bothering to take them on beyond other massive polar bears. Not only are they powerful hunters, but they’re incredibly patient, too.

Seals are a polar bear’s favorite meal, and as land-breathing mammals, they depend on holes in the ice to access air between swims. This is why clever polar bears will wait for seals by breathing holes as a kind of ambush hunting. A smart way to hunt, but they get smarter. 

There have been several reports of polar bears using ice and rocks to bonk walruses on the head, dating as far back as the 1700s, from Greenland and the eastern Canadian Arctic. However, for all their ingenuity, declining sea ice and extended warm periods are reducing the area they have to hunt, and some estimates predict they could be extinct by 2100.

Great white sh… (just kidding) – Orcas

I can’t include great white sharks in the list, and do you know why? Because orcas keep sucking out their livers like some sort of twisted crème caramel challenge, that’s why (they’ve even done it to the world’s largest shark).

Known as the “velociraptors of the sea” and – fittingly – killer whales, orcas are famous for their synchronized hunting techniques that can wash a seal off a block of ice and remove a shark’s liver with near-surgical precision. They are big, they are powerful, and they wear dead salmon as hats.

That they’re becoming an increasingly significant threat to human-made boats far bigger than they are is a testament to the fact that these are apex predators you do not want to mess with, and – it seems – neither do any of the other animals.

An impressive roster of animals, and there are plenty more out there, but perhaps it’s time for a hat-tip to the foundational species that make the food chain possible. After all, where would we be without photosynthesis?