Oyster toadfish adult and juvenile hiding among discarded human debris.
Oyster toadfish adult and juvenile hiding among discarded human debris.
Courtesy: NOAA

Oyster Toadfish (Opsanus tau)

Alternate common names: Toadfish, Dowdy.
Color: Blotchy, olive brown bodies fading to pale below. They are capable of changing color to match the bottom, and their eyes are blue.
Size: Up to 12 inches long.
Habitat: Sandy, rocky, and muddy bottoms on oyster reefs, shoal water, among eelgrass, hollows, or dens.
Seasonal appearance: All year.

Description

The oyster toadfish is an unusually shaped, large-headed fish that generally lives along oyster reefs and vegetated muddy bottoms. It has scaleless skin covered instead by thick mucous and sometimes warts, making it easy to understand why it earned the name "oyster toadfish." Out of water, this fish feels soft and squishy. Oyster toadfish have a tapering body with a plump belly and a large, flat head that tapers to a thin tail. Its nose is rounded, and it has a tremendous mouth with large, blunt teeth. Thick fleshy flaps of skin surround its lips and eyes. There are two sharp spines, located on the gill covers, which the oyster toadfish uses for defense. The ventral fins stretch out like fans and are located under its throat in front of the gill openings.

Life History and Behavior

Oyster toadfish are known to be quite vocal. When handled out of water, oyster toadfish grunt. To attract a female during the spawning season, the male emits a loud foghorn-like call. This call can be heard underwater for great distances. The female lays her eggs in rock crevices, under submerged wood, and sometimes even in discarded tin cans. After fertilization, the female leaves the male to guard the nest. For approximately one month, the male cleans the nest and uses his fins to fan the eggs until they hatch. The male continues guarding the young for three to four weeks after the eggs have hatched, keeping watch over them even after they become free-swimmers.

A voracious omnivore, the oyster toadfish feeds aggressively on American oysters, worms, shrimp, amphipods, crabs, hermit crabs, mollusks, squid, and small fish. The strong teeth and jaws of the oyster toadfish are capable of crushing the hard shells of mollusks and are often used to fight with other oyster toadfish. They snap viciously when caught.

Special Notes


Adapted from The Uncommon Guide to Common Life on Narragansett Bay. Save The Bay, 1998.