The coconut crab is the 800-pound gorilla of many tropical beaches. Not only is it the biggest and strongest crab on land, it’ll eat just about anything—animal, vegetable, or even mineral.

Coconut crabs are found in tropical environments in the Indian and southwestern Pacific oceans. They hatch in the sea, where they float around for a few weeks. They then move ashore, where they live in the discarded shells of other creatures. The crabs lose the shells when they become adults. They stay close to the beach, but they don’t go back in the water; they have lungs instead of gills, so they drown if they stay underwater for long.

An adult coconut crab has a leg span of about three feet, and can weigh up to nine pounds. It has powerful claws that can crack open a coconut and scoop out the meat. It can even climb a tree to knock a coconut to the ground.

The crabs also have been seen to climb trees to attack seabirds. Most of their diet consists of fruits, seeds, and dead animals. They eat abandoned shells for their calcium. But they sometimes grab birds, rats, or even other crabs. And they steal many human artifacts, from pots and pans to firearms, so they’re also known as robber crabs.

Coconut crabs have been wiped out in some regions. They’re hunted for their meat, crowded out by human development, and damaged by higher sea level and warmer oceans. Some areas offer legal protection—a helping hand—or claw—for these giants of the beach.