The Alabama shad (''Alosa alabamae'') is an

anadromous Fish migration is mass relocation by fish from one area or body of water to another. Many types of fish migrate on a regular basis, on time scales ranging from daily to annually or longer, and over distances ranging from a few metres to thousan ...

species of alosid fish

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

where it breeds in medium to large flowing rivers from the

Mississippi River The Mississippi River is the second-longest river and chief river of the second-largest drainage system in North America, second only to the Hudson Bay drainage system. From its traditional source of Lake Itasca in northern Minnesota, it f ...

drainage to the

Suwannee River The Suwannee River (also spelled Suwanee River) is a river that runs through south Georgia southward into Florida in the southern United States. It is a wild blackwater river, about long.U.S. Geological Survey. National Hydrography Dataset hig ...

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...

, as well as some other Gulf coast drainages. The biology of this fish is little known but it has become increasingly rare. The

International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

rated it "

near threatened A near-threatened species is a species which has been categorized as "Near Threatened" (NT) by the International Union for Conservation of Nature as that may be vulnerable to endangerment in the near future, but it does not currently qualify fo ...

" in 2020 and the

National Marine Fisheries Service The National Marine Fisheries Service (NMFS), informally known as NOAA Fisheries, is a United States federal agency within the U.S. Department of Commerce's National Oceanic and Atmospheric Administration (NOAA) that is responsible for the stew ...

has listed it as a Species of Concern. A principal reason for its decline is thought to be the many locks and

dam A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, a ...

s blocking access for the fish to up-river spawning grounds.

Description

The Alabama shad grows to be in length and may reach . The upper jaw of the fish bears a median notch. The Alabama shad has 42 to 48 gill rakers on the first gill arch's lower limb, which is intermediate between those of two

clupeids from the Atlantic coast, the

hickory shad The hickory shad (''Alosa mediocris''), fall herring, mattowacca, freshwater taylor or bonejack is a member of the herring family Clupeidae, ranging along the East Coast of the United States from Florida to the Gulf of Maine. It is an anadromou ...

(''Alosa mediocris'') and the

American shad The American shad (''Alosa sapidissima'') is a species of anadromous clupeid fish naturally distributed on the North American coast of the North Atlantic, from Newfoundland to Florida, and as an introduced species on the North Pacific coast. The ...

(''A. sapidissima''). It can be distinguished from

skipjack herring The skipjack herring (''Alosa chrysochloris'') is a North American, migratory, fresh- and brackish water fish species in the herring family Clupeidae. The name skipjack shad comes from the fact that it is commonly seen leaping out of the water wh ...

(''A. chrysochloris'') again by its gill raker count, as well as a lower jaw that is either equal in length to or extends only slightly beyond the upper, pigmented markings on its lower jaw that extend posteriorly beyond the cusp and the presence of only one row of teeth along its tongue. The dorsal fin usually has 16 or more rays and the last ray does not extend into a filament, unlike in

threadfin shad The threadfin shad (''Dorosoma petenense'') is a small pelagic fish common in rivers, large streams, and reservoirs of the Southeastern United States. Like the American gizzard shad, the threadfin shad has an elongated dorsal ray, but unlike the ...

(''Dorosoma petenense'') and American gizzard shad (''D. cepedianum'').

Distribution

The Alabama shad spawns in medium to large flowing rivers from the

drainage to the

, Florida. They are found in some Gulf coast drainages, but are thought to be extirpated from those drainages west of the

Pascagoula River The Pascagoula River is a river, about 80 miles (130 km) long, in southeastern Mississippi in the United States. The river drains an area of about 8,800 square miles (23,000 km²) and flows into Mississippi Sound of the Gulf of Mexico. ...

drainage in Mississippi.Adams, S.B., S.T. Ross, and M.L. Warren Jr. 2000. Literature review, information needs assessment, and research proposal for Gulf sturgeon, Alabama shad and American eel: diadromous fishes of USFS Region 8. USDA Forest Service, Southern Research Station, Center for Bottomland Hardwoods Research, Oxford, MS.Mettee, M.F., and P.E. O’Neil. 2003. Status of Alabama shad and skipjack herring in

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an oceanic basin, ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of ...

drainages. In: Limburg, K., and J. Waldman (eds) Biodiversity, status, and conservation of the world’s shads. American Fisheries Society Symposium 35, Bethesda, MD, p 157-170. 11/1/2007 3Boschung, H.T., and R.L. Mayden. ''Fishes of Alabama''. Smithsonian Books, Washington D.C. 2004. pp 736.

Ecology

Alabama shad are a

schooling A school is an educational institution designed to provide learning spaces and learning environments for the teaching of students under the direction of teachers. Most countries have systems of formal education, which is sometimes compuls ...

species. Within sandbar and channel habitat types in the

, Mickle (2010) found that juvenile shad preferred locations with cooler water temperatures. Juveniles remain in fresh water for the first six to eight months of their lives, feeding on small fishes and invertebrates.

Biology

The biology of the species is not well known. Spawning usually occurs around in Gulf of Mexico drainages. Alabama shad historically ran as far northeast as the

Monongahela River The Monongahela River ( , )—often referred to locally as the Mon ()—is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map accessed August 15, 2011 river on the Allegheny Plateau in North Cen ...

to spawn, likely in mid-June. Males seemingly weigh less than the females and mortality occurs after spawning as with numerous other species of the ''Alosa'' genus, although repeat spawning, as determined by counting of spawning marks on scales, has been described in certain drainage populations. The fish lives for approximately three or four years.

Evolution

The closest living relative of ''Alosa alabamae'' is the

, ''A. sapidissima''. The ancestor of ''A. alabamae'' may have swum around the Florida peninsula and become geographically isolated no earlier than the

Pleistocene epoch The Pleistocene ( , often referred to as the ''Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in ...

Conservation

Although once abundant enough to support commercial fisheries in Alabama, Arkansas, Kentucky, Indiana and Iowa, Alabama shad are now rare throughout much of their former range. At one point, ''Alosa alabamae'' were found in the Ohio River as well. The species is thought to have declined largely because of the many locks and dams blocking access to spawning areas and alterations in hydrology and river substrates. The Alabama shad is a U.S.

Species of Concern, one of those species about which the U.S. Government's

National Oceanic and Atmospheric Administration The National Oceanic and Atmospheric Administration (abbreviated as NOAA ) is an United States scientific and regulatory agency within the United States Department of Commerce that forecasts weather, monitors oceanic and atmospheric conditio ...

has some concerns regarding status and threats, but for which insufficient information is available to indicate a need to list the species under the U.S.

Endangered Species Act The Endangered Species Act of 1973 (ESA or "The Act"; 16 U.S.C. § 1531 et seq.) is the primary law in the United States for protecting imperiled species. Designed to protect critically imperiled species from extinction as a "consequence of ec ...

(ESA). On April 20, 2010, a number of organizations submitted a petition to list the species as threatened or endangered under the ESA, which was initially rejected. On September 19, 2013, however, the

(NMFS) published a 90-day finding that listing under the ESA may be warranted and announced the initiation of a status review.NMFS. ''Endangered and Threatened Wildlife; 90-Day Finding on a Petition To List Alabama Shad as Threatened or Endangered Under the Endangered Species Act''.''Federal Register'' v78, (September 19, 2013), 57611-57616. The NMFS denied ESA listing for ''A. alabamae'' in its 12-month finding, published in 2017, though it also found that there was uncertainty in the sampling data and scarce historical data available to support a decision. A more recent study by Rider, Powell, Dattilo & Miles (2021) concluded that the Alabama shad had likely been extirpated from the

Mobile River The Mobile River is located in southern Alabama in the United States. Formed out of the confluence of the Tombigbee and Alabama rivers, the approximately river drains an area of of Alabama, with a watershed extending into Mississippi, Georg ...

basin and that a 98% decline in abundance occurred between 1999–2000 and 2018 in the Choctawhatchee River. They observed a small number of shad in the Conecuh River in 2010. It is likely that the largest remaining population is the one that spawns in the

ACF River Basin The ACF River Basin is the drainage basin, or watershed, of the Apalachicola River, Chattahoochee River, and Flint River, in the Southeastern United States. This area is alternatively known as simply the Apalachicola Basin and is listed by t ...

(Apalachicola/Chattahoochee/Flint River system). The

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...

indicates ''A. alabamae'' as a near-threatened species. The

American Fisheries Society The American Fisheries Society (established 1870 in New York City), is the "world’s oldest and largest organization dedicated to strengthening the fisheries profession, advancing fisheries science, and conserving fisheries resources." It is a mem ...

lists it as threatened.

References

External links

*Froese, R. and D. Pauly
''Alosa alabamae''.
FishBase. 2015. * {{Taxonbar, from=Q301472 Alosa Freshwater fish of the Southeastern United States Fish of the Eastern United States Fish of the Gulf of Mexico Mississippi River Natural history of Alabama Taxonomy articles created by Polbot Fish described in 1896 Taxa named by David Starr Jordan Taxa named by Barton Warren Evermann