Atlantic mudskipper

Mudskippers catch food on the mud.

They eat little crabs and insects. They also eat bits of green algae and plants.

Atlantic mudskippers hunt on the open mud at low tide. The IUCN says grown-ups mainly eat small crabs, insects and other little animals with jointed legs on the mud's surface, and also part of a mangrove tree, the white mangrove.

A year-long study in Nigeria found that mudskippers there ate lots of algae and bits of dead plant matter too, plus crabs and insects. Scientists call this kind of animal a generalist, because it eats many different things.

The IUCN and FishBase describe adults feeding chiefly on arthropods of the mud surface (crabs, insects), with white mangrove (Avicennia) also in the diet. A 12-month study in Nigeria's Imo River Estuary (Udo, 2002) found a broader, omnivorous diet: detritus and benthic algae were the main items; crustaceans, insects and plant matter were minor; and the diet shifted with the seasons, with more algae and sesarmid crabs in the dry season.

Feeding on land is remarkable. Michel and colleagues report that the Atlantic mudskipper feeds mainly on land, holding water in its mouth and pushing it forward as it strikes, a "hydrodynamic tongue", then closing its jaws over the prey.

When the tide goes out, mudskippers come out.

They skip and walk across the mud to find food. When the water comes back, they can swim too.

Mudskippers live in two worlds. When the tide goes out, they skip or walk across the wet mud, hunting for food. They can feed both on land and in water, which very few animals with backbones can do well.

In water, a mudskipper opens its gill covers and sucks food in, like most fish. On land, it keeps its gill covers closed and uses the water held in its mouth to help grab its meal. It changes how its mouth works depending on where it is. Scientists even compare its fins with salamander legs to learn how the first animals with backbones moved onto land.

Few vertebrates capture prey both in water and on land, because the two media make conflicting demands. Michel and colleagues (2016) found that the Atlantic mudskipper switches technique: in water, its gill slits open before the strike and larger head expansion produces strong suction; on land, the gill slits stay closed and a smaller expansion drives its hydrodynamic tongue.

On exposed mud flats it skips or walks over sand and mud in search of food (IUCN). On land it moves by "crutching" on its pectoral fins. Kawano and Blob (2013) measured the forces these fins produce and compared them with the legs of tiger salamanders, to help understand how early vertebrates first moved onto land.

There are lots of Atlantic mudskippers.

People in some places catch them to eat. Keeping muddy shores and mangroves clean helps them.

The IUCN lists the Atlantic mudskipper as Least Concern. It can be common in the right places, and its range overlaps several protected areas by the sea.

People catch mudskippers to eat, to use as fishing bait and to sell as aquarium pets, though there is no big commercial fishery. Building along the coast, water pollution and harmful fishing methods could hurt them in some places.

The IUCN assessed P. barbarus as Least Concern on 20 October 2019 (published 2020; also LC in 2010). It is common in museum collections and locally abundant, though its overall trend is unknown.

There is no commercial fishery, but it is harvested for food, bait and the aquarium trade. Coastal development, water pollution and destructive fishing could affect it, but the assessors judged these threats local. No species-specific conservation measures exist; the range overlaps several marine protected areas, and the assessors suggest policy measures such as regulated fishing quotas.