Alabama shad

The Alabama shad (Alosa alabamae) is an anadromous species of clupeid fish endemic to the United States where it breeds in medium to large flowing rivers from the Mississippi River drainage to the Suwannee River, Florida, 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 rated it "near threatened" in 2020[1] and the United States National Marine Fisheries Service has listed it as a Species of Concern. A principal reason for its decline is thought to be the many locks and dams blocking access for the fish to up-river spawning grounds.[2]

Alabama shad

Imperiled  (NatureServe)[2]
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Clupeiformes
Family: Alosidae
Genus: Alosa
Species:
A. alabamae
Binomial name
Alosa alabamae
Jordan & Evermann in Evermann, 1896
Synonyms[3]
  • Alosa ohiensis (Evermann, 1902)

Description

The Alabama shad grows to be 12–18 inches (30–46 cm) in length[4] and may reach 3 pounds (1.4 kg).[5] The upper jaw of the fish bears a median notch.[6] The Alabama shad has 42 to 48 gill rakers on the first gill arch's lower limb,[7] which is intermediate between those of two anadromous clupeids from the Atlantic coast, the hickory shad (Alosa mediocris)[8] and the American shad (A. sapidissima).[9] It can be distinguished from skipjack herring (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.[5] The dorsal fin usually has 16 or more rays and the last ray does not extend into a filament, unlike in threadfin shad (Dorosoma petenense) and American gizzard shad (D. cepedianum).[5]

Distribution

The Alabama shad spawns in medium to large flowing rivers from the Mississippi River drainage to the Suwannee River, Florida. They are found in some Gulf coast drainages, but are thought to be extirpated from those drainages west of the Pascagoula River drainage in Mississippi.[10][11][12]

Ecology

Alabama shad are a schooling species. Within sandbar and channel habitat types in the Pascagoula River, Mickle (2010) found that juvenile shad preferred locations with cooler water temperatures.[13] Juveniles remain in fresh water for the first six to eight months of their lives, feeding on small fishes and invertebrates.[14]

Biology

The biology of the species is not well known. Spawning usually occurs around 19–23 °C (66–73 °F) in Gulf of Mexico drainages.[15] Alabama shad historically ran as far northeast as the Monongahela River[16]: 276  to spawn, likely in mid-June.[16]: 283  Males seemingly weigh less than the females and mortality occurs after spawning as with numerous other species of the Alosa genus,[15] although repeat spawning, as determined by counting of spawning marks on scales, has been described in certain drainage populations.[11] The fish lives for approximately three or four years.[17]

Evolution

The closest living relative of Alosa alabamae is the American shad, A. sapidissima.[6][18] The ancestor of A. alabamae may have swum around the Florida peninsula and become geographically isolated no earlier than the Pleistocene epoch.[18]

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.[10][14] At one point, Alosa alabamae were found in the Ohio River as well.[19] 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.[10][11][12][14]

The Alabama shad is a U.S. National Marine Fisheries Service Species of Concern, one of those species about which the U.S. Government's National Oceanic and Atmospheric Administration 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 (ESA).[20] 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.[21] On September 19, 2013, however, the National Marine Fisheries Service (NMFS) published a 90-day finding that listing under the ESA may be warranted and announced the initiation of a status review.[22] 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.[6]

A more recent study by Rider, Powell, Dattilo & Miles (2021) concluded that the Alabama shad had likely been extirpated from the Mobile River basin and that a 98% decline in abundance occurred between 1999–2000 and 2018 in the Choctawhatchee River.[23] They observed a small number of shad in the Conecuh River in 2010.[23]: 141  It is likely that the largest remaining population is the one that spawns in the ACF River Basin (Apalachicola/Chattahoochee/Flint River system).[6]

The IUCN Red List indicates A. alabamae as a near-threatened species.[1] The American Fisheries Society lists it as threatened.[2]

References
  1. Sammons, S.; Young, S.; Carlson, J. (2021). "Alosa alabamae". IUCN Red List of Threatened Species. 2021: e.T908A3149565. doi:10.2305/IUCN.UK.2021-1.RLTS.T908A3149565.en. Retrieved 15 November 2021.
  2. NatureServe (30 September 2022). "Alosa alabamae". NatureServe Network Biodiversity Location Data. Arlington, Virginia: NatureServe. Retrieved 31 December 2022 – via NatureServe Explorer.
  3. dsantos (5 August 2014). "Synonyms of Alosa alabamae (Jordan & Evermann, 1896)". FishBase. Retrieved 31 December 2022.
  4. Mettee, Maurice F.; O'Neil, Patrick E.; Pierson, J. Malcolm. "Alabama Shad, excerpt from Fishes of Alabama and the Mobile Basin (1996)". Outdoor Alabama. Alabama Department of Conservation and Natural Resources. Retrieved 31 December 2022.
  5. "Field Guide: Alabama Shad". Missouri Department of Conservation. Retrieved 31 December 2022.
  6. National Oceanic and Atmospheric Association (12 January 2017). "Endangered and Threatened Wildlife and Plants: Notice of a 12-Month Finding on a Petition to List Alabama Shad as Threatened or Endangered Under the Endangered Species Act". Federal Register. 82 (8): 4022–4067. 82 FR 4022. Retrieved 31 December 2022.
  7. "Discover Fishes: Alabama Shad". Florida Museum. 19 August 2022. Retrieved 31 December 2022.
  8. "Discover Fishes: Hickory Shad". Florida Museum. 19 August 2022. Retrieved 31 December 2022.
  9. "Species: Alosa sapidissima, American shad". Smithsonian Tropical Research Institute. 2015. Retrieved 31 December 2022.
  10. 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.
  11. Mettee, M.F., and P.E. O’Neil. 2003. Status of Alabama shad and skipjack herring in Gulf of Mexico 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 3
  12. Boschung, H.T., and R.L. Mayden. Fishes of Alabama. Smithsonian Books, Washington D.C. 2004. pp 736.
  13. Mickle, P.F. (December 2010). Life History and Habitat Use of the Juvenile Alabama Shad, Alosa alabamae, in Northern Gulf of Mexico Rivers (PhD). The University of Southern Mississippi. Retrieved 2 January 2023 – via The Aquila Digital Community.
  14. Ross, Stephen T. (2001). Inland Fishes of Mississippi. Jackson: University Press of Mississippi. ISBN 1-57806-246-2. Retrieved 2 January 2023 – via The University of Southern Mississippi.
  15. Ingram, Travis R. (May 2007). Age, growth, and fecundity of Alabama shad (Alosa alabamae) in the Apalachicola River, Florida. All Theses (MSc). Clemson University. Retrieved 2 January 2023 – via TigerPrints, All Theses.
  16. Evermann, Barton Warren (1902). "Description of a New Species of Shad (Alosa ohiensis), with Notes on Other Food-Fishes of the Ohio River" (PDF). In Bowers, George M. (ed.). U.S. Commission of Fish and Fisheries, George M. Bowers, Commissioner, Part 27: Report of the Commissioner for the Year Ending June 30, 1901. Washington: Government Printing Office. pp. 275–288. Retrieved 31 December 2022 – via Penobscot Bay Watch.
  17. McAllister, Chris T. (28 September 2021). "Herrings". The CALS Encyclopedia of Arkansas. Retrieved 4 January 2023.
  18. Bowen, B.R.; Kreiser, B.R.; Mickle, P.F.; Schaefer, J.F.; Adams, S.B. (2008). "Phylogenetic relationships among North American Alosa species (Clupeidae)". Journal of Fish Biology. 72 (5): 1188–1201. doi:10.1111/j.1095-8649.2007.01785.x. Retrieved 4 January 2023 – via Forest Service, U.S. Department of Agriculture.
  19. Pearson, William D.; Pearson, B. Juanelle (1989). "Fishes of the Ohio River" (PDF). The Ohio Journal of Science. 89 (5): 181–187. S2CID 8557656. Retrieved 2 January 2023 – via The Ohio State University.
  20. Species of Concern NOAA
  21. National Oceanic and Atmospheric Association (17 February 2011). "Endangered and Threatened Wildlife; 90-Day Finding on a Petition To List Alabama Shad as Threatened or Endangered Under the Endangered Species Act (ESA)". Federal Register. 76 (33): 9320–9321. Retrieved 4 January 2023.
  22. 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.
  23. Rider, Steven J.; Powell, Travis R.; Dattilo, Jason E.; Miles, Gregory T. (2021). "Status and Relative Abundance of Alabama Shad, Alosa alabamae, in Alabama". Southeastern Fishes Council Proceedings. 1 (61): 136–155. Article no. 5. Retrieved 2 January 2023 – via The University of Tennessee Knoxville.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.