The Atlantic croaker (''Micropogonias undulatus'') is a species of marine

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of sk ...

belonging to the family Sciaenidae and is closely related to the black drum ('' Pogonias cromis''), the silver perch ('' Bairdiella chrysoura''), the spot croaker ('' Leiostomus xanthurus''), the red drum ('' Sciaenops ocellatus''), the spotted seatrout ('' Cynoscion nebulosus''), and the weakfish ('' Cynoscion regalis''). It is commonly found in sounds and estuaries from

Massachusetts Massachusetts ( ; ), officially the Commonwealth of Massachusetts, is a U.S. state, state in the New England region of the Northeastern United States. It borders the Atlantic Ocean and the Gulf of Maine to its east, Connecticut and Rhode ...

to the

Gulf of Mexico The Gulf of Mexico () is an oceanic basin and a marginal sea of the Atlantic Ocean, mostly surrounded by the North American continent. It is bounded on the northeast, north, and northwest by the Gulf Coast of the United States; on the southw ...

Description

The name croaker is descriptive of the noise the fish makes by vibrating strong muscles against its

swim bladder The swim bladder, gas bladder, fish maw, or air bladder is an internal gas-filled organ (anatomy), organ in bony fish that functions to modulate buoyancy, and thus allowing the fish to stay at desired water depth without having to maintain lift ...

, which acts as a resonating chamber much like a ball. The Atlantic croaker is the loudest of the drum family. It is also referred to as a hardhead, with smaller ones called pin heads. During spawning season (August to October), croakers turn a deep golden color, from this comes the name golden croaker. Beginning in August, tiny young enter the

Chesapeake Bay The Chesapeake Bay ( ) is the largest estuary in the United States. The bay is located in the Mid-Atlantic (United States), Mid-Atlantic region and is primarily separated from the Atlantic Ocean by the Delmarva Peninsula, including parts of the Ea ...

and travel to low-salinity and freshwater creeks. They move to deeper parts of tidal rivers for the winter. Juveniles leave the bay with the adults the following autumn. When full-grown at 2 to 3 years old, croakers reach between 18 and 20 inches in length long and 4 to 5 pounds, but on average are 1/2-2 pounds. The fish's lifespan can reach up to 8 years. The Chesapeake Bay record Atlantic croaker, caught in August 2007 off New Point Comfort Lighthouse in Virginia, weighed 8 pounds, 11 ounces and measured 27 inches long. They have traditionally been used for food by Native Americans, and their remains are found in shell middens. These fish are popular catches among recreational anglers.

Distribution and habitat

The Atlantic croaker is native to coastal waters in the western Atlantic Ocean. Its range extends from Massachusetts to Mexico and includes the northern half of the Caribbean Sea but possibly not the southern Gulf of Mexico or the Antilles. It is also thought to live on the coasts of southern Brazil and Argentina. It is usually found in bays and estuaries over sandy or muddy bottoms where it feeds on polychaete worms,

crustacean Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthrop ...

s and small fish. The croaker visits the

from March through October and is found throughout the Bay as far north as the Susquehanna Flats.

Management

Croaker populations greatly vary from year to year, and can be dependent on the conditions of their habitats. Their management is challenging due to the variability in their numbers. Due to a wide range and large population, croaker are listed as species of Least Concern by the IUCN.

Importance in scientific research

In 1999, an

androgen receptor The androgen receptor (AR), also known as NR3C4 (nuclear receptor subfamily 3, group C, member 4), is a type of nuclear receptor that is activated by binding any of the androgenic hormones, including testosterone and dihydrotestosterone, in th ...

protein called ZIP9 Protein was discovered in the

brain The brain is an organ (biology), organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It consists of nervous tissue and is typically located in the head (cephalization), usually near organs for ...

ovary The ovary () is a gonad in the female reproductive system that produces ova; when released, an ovum travels through the fallopian tube/ oviduct into the uterus. There is an ovary on the left and the right side of the body. The ovaries are end ...

and testicular tissues of Atlantic croaker.

References

* Robins, C. Richard, G. Carleton Ray, and John Douglass. A Field Guide to Atlantic Coast Fishes-North America. Houghton Mifflin Company. New York. 1986. 184–188. {{Authority control Atlantic croaker Seafood in Native American cuisine Fish described in 1766 Fish of the Atlantic Ocean Taxa named by Carl Linnaeus