Gulf Sturgeon

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Gulf Sturgeon

Acipenser oxyrinchus desotoi

Status Threatened
Listed September 30, 1991
Family Acipenseridae
Description A large, fusiform fish with an extended snout, ventral mouth, chin barbels, and the upper lobe of the tail longer than the lower.
Habitat Large rivers and estuaries.
Food Feeds on aquatic invertebrates and small fish.
Reproduction Lays numerous eggs in a benthic nest.
Threats Habitat destruction and degradation by dredging, pollution, and other stressors.
Range Alabama, Florida, Georgia, Louisiana, Mississippi, Texas

Description

The Acipenser oxyrinchus desotoi (Gulf sturgeon) has a fusiform (or cylindrical) body with an extended snout, ventral mouth, chin barbels, and the upper lobe of the tail longer than the lower. Adults range from 6-8 ft (1.8-2.4 m) in length, with adult females larger than males. It is a subspecies of the Atlantic sturgeon (Acipenser oxyrinchus ), and is distinguished from the East Coast subspecies (A. o. oxyrinchus ) by its longer head, pectoral fins, and spleen.

Behavior

The Gulf sturgeon is an anadromous species that migrates between fresh and salt water. It feeds on or near the bottom on aquatic invertebrates and small fish.

Habitat

The Gulf sturgeon breeds in fresh water of large rivers, and may feed in fresh or salt water. During its annual migration, it requires nearshore (bays and estuaries) and offshore (Gulf of Mexico) feeding areas and freshwater rivers with adequate water quality and quantity, hard bottoms for spawning, and spring flows and deep holes for thermal refugia.

Distribution

The Gulf sturgeon is restricted to the Gulf of Mexico and its drainages, primarily from the Mississippi River to the Suwannee River, including the States of Alabama, Florida, Georgia, Louisiana, and Mississippi. Sporadic occurrences are known as far west as Texas (Rio Grande), and marine waters in Florida south to Florida Bay.

Threats

The Gulf sturgeon has suffered from excessive direct fishing, by-catch in nets set for other species, and habitat destruction and degradation caused by dredging, hydrologic management, siltation, and pollution by sewage, nutrients, and pesticides.

Conservation and Recovery

The Gulf sturgeon is now protected from fishing throughout its range. An Interjurisdictional Fishery Management Plan has been prepared for the species by the Gulf States Marine Fisheries Commission. It is also covered by the draft Mobile River Basin Aquatic Ecosystem Recovery Plan prepared by the Fish and Wildlife Service, and by the Suwannee River Cooperative River Basin Study. The population status of the Gulf sturgeon is being monitored, and research has been undertaken to better understand its biology and ecological requirements. The Mobile District of the U.S. Army Corps of Engineers has worked with conservation agencies on projects to improve habitat for the Gulf sturgeon. This includes efforts to restore thermal refugia habitat and access into Battle Bend Cutoff and the Blue Spring Run in the Apalachicola River, and studies to monitor the Pearl River Gulf sturgeon populations.

Contact

U. S. Fish and Wildlife Service
Jacksonville Ecological Services Field Office
6620 Southpoint Drive South, Suite 310
Jacksonville, Florida 32216-0958
Telephone: (904) 232-2580

Reference

U.S. Fish and Wildlife Service. 23 Aug. 1995. "Endangered and Threatened Wildlife and Plants: Decision on Designation of Critical Habitat for the Gulf Sturgeon." Federal Register 60(163): 43721-43723.

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Gulf Sturgeon

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