What eats crabs? Well actually, the first thing that comes to mind when you think of crabs is the fact that they have big claws and can be found in many different colors, sizes, and shapes. But we often don’t realize that animals of many different sizes and shapes also predate various kinds of crabs.
The wide array of “what eats crabs” is what we’re going to list in this article.
Crabs are classed as arthropods and contain more than 6,000 species within around 93 arthropod families. These include blue crab, king crab, ghost crab, spider crab, fisherman crab, and many more. 400 hundred of these species are freshwater crabs.
However, there are actually more than 20,000 species of crabs worldwide!
We have to remember that many crabs are quite small and therefore more vulnerable, so defending themselves is tougher. This opens up the number of potential predators of crabs.
There are times when exiting old shells to form new larger shells also creates a greater period of vulnerability for a crab.
Plus not all crabs are totally encased in their shells, so there are more weak points in their armor. The hermit crab is perhaps a good example of that. But as the image below shows, for larger and more powerful predators, even the toughest shell can be overcome.
So what eats crabs? Let’s get into some details…
Here’s what eats crabs
It seems like every animal has an appetite for something. And while humans eat crabs, there are also plenty of other creatures who eat them too.
In fact, there are over 400 known species of crabs that are eaten by other animals. These predators include fish, reptiles, amphibians, birds, bats, parasites, and other crustaceans.
Below is a quick reference table, then we’ll get into some more interesting facts about what eats crabs.
|Large sea birds
|Some frogs (Amphibians)
Fish eat crabs
Fish are probably one of the best-known predators of crabs. Some larger fish use their teeth to tear off chunks of flesh from the shell of a crab.
Smaller fish are able to hunt and consume crab larvae and juvenile crabs, which widens the pool of predators. Fish such as sharks, dogfish, striped bass, red drum, black drum, Atlantic croaker, cobia, eels, sea rays, and jellyfish are among those that hunt, attack, and eat crabs.
Larger fish swallow the meat and spit out the empty shell. Fish do this with a variety of crabs including hermit crabs, mud crabs, spiny lobsters, and king crabs.
Fish that eat crabs include:
- Dog fish
- Striped bass
- Red drum
- Black drum
- Atlantic croaker
- American eel
- Sea ray
Reptiles eat crabs
Snakes are actually a common predator of crabs. They’ll often wait until the crab goes to sleep before eating it. This includes sea snakes, boa constrictors, pythons, and cobras.
Lizards will sometimes eat crabs if they find them under rocks, shallow water, or crevices.
Again due to many smaller sizes of crabs, not to mention young crabs, means there are a number of reptiles that eat crabs.
Reptiles that eat crabs include:
- Boa constrictor
- Sea snake
- Monitor lizard
Mammals that eat crabs
There are a number of mammals that eat crabs. These include sea otters, seals, sea lions, walrus, whales, dolphins, porpoises, raccoons, and even some bats.
Sea otters will often dive down to the seafloor and search for crabs, then they’ll use their paws to break open the shells.
There are also whales, dolphins, and porpoises that will eat crabs when given the opportunity. Their powerful jaws can make quick work of disabling a crab by crushing its shell.
Pinnipeds like walrus, seals, and sea lions also eat crabs.
There are bats that will eat crabs. One species, the fisherman bat, will feed on fiddler crabs as part of their diet of fish and other crustaceans.
Raccoons also eat crabs, including the blue crab, Dungeness crab, Jonah crab, and rock crab. They use their front paws to separate the meat from the shell. Then they scoop out the crab meat and eat it
Mammals that eat crabs include:
- Sea otters
- Sea lions
Birds eat crabs
There are many kinds of birds that eat crabs, particularly targeting crab larvae or juvenile crabs. Larger birds will feed on adult crabs. Herons are one type of large bird predator whose beak is used to spear crab to subdue them.
Here’s the list of what herons eat.
Gulls and other seabirds can be found along beaches at low tide, looking for crabs that are washed ashore. They will turn them over while avoiding their claws, break into their shells and feed on them. Be it Egrets, herons, and even diving ducks
What eats crabs – other animals
In addition to the animals listed above, a number of other animals also eat crabs. They include:
Octopuses (Cephalopod) eat some species of crab. Some frogs (Amphibians) also eat juvenile crabs.
Crabs are a popular food item for many animals, both on land and in the water. In the wild, they are a source of important nutrition for mammals, reptiles, amphibians, and birds.
Cannibalism occurs often among many crab species.
Other animals that eat crabs include crab spiders which only prey on crabs when they emerge from the water. As well as mud crabs, hermit crabs, and mud shrimp.
And of course, humans also eat crabs…
Humans eat crabs
It may seem like we humans eat just about everything, but it turns out that we don’t really eat all that much in terms of crabs.
In fact, only around 1% of our food intake comes from meat. The rest comes from plants, fruits, vegetables, grains, nuts, seeds, dairy products, and eggs.
That means that 99% of our food intake is made up of plant matter. But of that 1%, a small portion is made up of seafood, and of that, a fraction is made up of crabs.
What eats crabs – crab specific predators
Let’s look at some more specific crab species and scenarios in which crabs are predated by other animals.
What eats deep-sea crabs
Out in the deep ocean, as opposed to around shorelines, crabs are predominantly attacked by larger fish, such as sharks, rays, porpoises, and dolphins. Crab larvae are also scooped up by whales.
What animal eats king crabs
Red king crab larvae and juveniles are eaten by fish such as cod, halibut, sculpins, and yellowfin sole, as well as octopuses and whales, plus other king crabs! They are also preyed upon by sea otters, seals, sharks, and dolphins.
What eats blue crabs
Blue crab larvae and juveniles are eaten by predators including cod, striped bass, red drum, and Atlantic croaker. Birds such as blue herons and gulls also predate blue crabs and larger blue crabs are eaten by sea creatures such as sharks, dolphins, and porpoises.
Do octopuses eat crabs
Octopuses do eat crabs. Blue crabs in particular are a popular food source for many species of octopus. Octopus use salivary glands to dispense neurotoxin which paralyzes the crab, followed by enzymes that serve to dissolve the food inside the crab’s shell, creating a crab cocktail they can consume.
What eats crabs – summary
Crabs are a popular food source for many predators, ranging from fish and birds to sea creatures such as sharks, dolphins, and porpoises.
Even octopuses love to eat crabs! So if you’re ever out crabbing and see an octopus hanging around, watch out – your catch might just get stolen by an octopus!
Be sure to check out many other interesting facts and animal information on Ranger Planet.