How A River Otter Bags An Alligator (National Geographic)

A hungry river otter in Florida's Lake Woodruff National Wildlife Refuge attacks an alligator in the water.

PHOTOGRAPH BY GEOFF WALSH

Jennifer S. Holland

for National Geographic

PUBLISHED MARCH 6, 2014

We've barely recovered from the snake-eats-croc photos, and now this: Photos reveal a river otter in Florida attacking a young alligator, which it then ripped into for lunch.

The photos, shot in 2011 in Florida's Lake Woodruff National Wildlife Refuge by a visitor named Geoff Walsh, were posted this week on the refuge's Facebook page. Our favorite reptile expert, Terry Phillip, had this initial reaction: "Man, that's a bold and hungry otter! Very cool."

We asked Phillip, of Reptile Gardens in South Dakota and Black Hills Pythons, to tell us more about how such a battle might go down.

A cute-faced mammal killing a powerful gator? Wildlife is full of surprises. How common might it be for a river otter to take on such an animal?

Otters are voracious predators, close to being apex [top predator] inmost places where they live. So anywhere they overlap with gators this would be a pretty common occurrence. Still, this is impressive: That's not a small alligator, probably three or four years old and five feet [1.5 meters] long. If that's a male otter it might be 30 pounds. That's a very bold animal!

PHOTOGRAPH BY GEOFF WALSH

How does the otter know to bite the gator behind the head?

It's actually a learned behavior. That otter has probably tried attacking smaller ones and got some bites to learn from. Remember that crocs swing their heads side to side when they fight, so the otter wants to be entirely out of the reptile's strike zone. Mounted on the gator's back with teeth into the neck, that's a smart strategy.

How does the otter actually kill the gator?

It doesn't, not directly. First, that's a pretty hard animal to bite through.The armor on the back is made to deflect bites from other alligators, so it's very tough. Where the otter wins is in energy: The otter hassustainable energy, whereas the gator is like a grenade, with explosive energy that doesn't last long. So the best tactic is to wear the gator out, which only takes a few minutes of thrashing and rolling around. Quite quickly it will be very tired, its muscles filled with lactic acid and no longer functioning. At that point it's almost like it's intoxicated, and the otter can then get it up on shore. The gator dies of lactic acid buildup, not from being eaten. It would take a long time to kill it that way.

So the otter eats its prey alive?

Yeah, once on shore it will rip off pieces of the hide—otters have very sharp teeth—to get to the guts and meat, the good stuff, inside. A lot of parts will end up scattered around. It's like a lion's kill as opposed to a snake's. If there's a mated pair or young otters, they'll get a piece of it, too. It's a good education for otter pups.

What other big animals might an otter eat?

Whatever they can catch and overpower. They are smart, agile, and strong predators. They do eat a lot of amphibians and fish, but they'll also take out sizeable beavers, raccoons, plus snapping turtles, snakes, and small gators. Of course, gators can also eat otters, so it goes both ways!

And what else might go for a gator?

When they're hatchlings, everything eats them. Large fish, snapping turtles, bird of prey. Bobcats and panthers and black bears can certainly eat young ones. (See video: jaguar attacks caiman.) But once the gators are good-sized, the only predator that will typically beat one is another gator. And, apparently, an otter if it's hungry enough!