Shad, Alabama

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Shad, Alabama

Alosa alabamae

phylum: Chordata

class: Osteichthyes

order: Clupeiformes

family: Clupeidae

status: Endangered, IUCN

range: USA (Alabama)

Description and biology

The Alabama shad spawns (lays its eggs) in rivers but spends some part of its life living in the ocean. It is a silvery-green fish that measures about 20 inches (51 centimeters) in adulthood. Females are larger than males. It has a distinctive pointed snout with a lower jaw jutting out from inside the mouth. It has 42 to 48 gill rakers, which are bony projections that point forward and inward from the gill raker arches to aid in the fish's feeding. (Gill raker arches are bony arches in the throat of fish to which the gill rakers are attached—bony fish usually have four gill arches.)

Alabama shad travel in schools. In the winter and spring, when the water temperatures are cool, the shad travel up rivers and streams to spawn. They prefer to spawn over sand, gravel, or rocky surfaces in a moderate current. The male and female will leave the area after the spawning is complete. The young remain in the stream for several months. The Alabama shad's life span is about six years.

Habitat and current distribution

The Alabama shad spawns in medium- and large-sized rivers. It can be found in the eastern part of the Gulf of Mexico, from the Mississippi delta east to the Choctawhatchee River in Florida and also in the Cumberland, Tennessee, Missouri, Arkansas, Ouachita, and Red rivers. The largest existing population occurs in the Apalachicola River in northwest Florida. The exact population of this species is unknown.

History and conservation measures

The decline in the population of Alabama shad began with overfishing in the nineteenth and early twentieth centuries. Other human-related threats began to disturb the shad's life cycle as the twentieth century progressed. Particularly damaging was poor water quality due to commercial and navigational dredging (digging up the bottom) of the sand bars that the shad use for spawning. However, the greatest cause of decline in the Alabama shad population in Alabama is the series of dams built in the Alabama and Tombigbee rivers. These dams block the fish from their travels to spawn in the Mobile Basin, the region where the two rivers drain in Alabama.

Recovery programs for the Alabama shad are not yet underway, and the fish was not listed under the Endangered Species Act as of the early 2000s, despite its endangered status on the International Union for the Conservation of Nature and Natural Resources (IUCN) Red List. However, the U.S. Fish and Wildlife Service was creating a status report on the Alabama shad, hoping to begin action to protect the species.

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