Allis shad
Allis shad | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Clupeiformes |
Family: | Alosidae |
Genus: | Alosa |
Species: | A. alosa
|
Binomial name | |
Alosa alosa |
The allis shad (Alosa alosa) is a widespread Northeast Atlantic species of fish in the herring family, Clupeidae. It is an anadromous fish which migrates into fresh water to spawn.[2][3] It is found in the eastern Atlantic Ocean, the western Baltic Sea and the western Mediterranean Sea. In appearance it resembles an Atlantic herring but has a distinctive dark spot behind the gill cover and sometimes a row of up to six spots behind this. It sometimes hybridises with the twait shad (A. fallax). This fish becomes mature when three or more years old and migrates to estuaries, later swimming up rivers to spawn. Populations of this fish have declined due to overfishing, pollution and habitat destruction. Conservation of this species is covered by Appendix III of the Bern Convention and Appendix II and V of the European Community Habitats Directive.
Description
The allis shad is a typical herring-type fish. It has no
Distribution
The allis shad is found in the eastern Atlantic in waters bordering most of
Biology and lifecycle
Alosa alosa has a similar lifecycle to that of the
Population reduction
Populations have been reduced primarily by overfishing, pollution, and habitat destruction.[6] The estuarine phase, or the time that they are in the estuaries migrating from spawning grounds to sea, is estimated to have a duration in A. alosa of up to six months.[5] The estimate, however, does not take into account individual variation and/or survival of juveniles in the estuarine phase.[5]
Conservation
Four special areas of conservation have been designated in Ireland where Alosa species have been known to spawn.[6] Alosa alosa "has been placed in Appendix III of the Bern Convention (1979) that lists protected fauna species as well as in Appendix II and V of the European Community Habitats Directive (1992) that list, respectively, species whose conservation requires the designation of special areas of conservation and that are subject to management measures."[5] However, A. alosa is currently under a moratorium (2008) in numerous French watersheds.[5]
References
- ^ . Retrieved 15 November 2021.
- ^ a b c Froese, Rainer; Pauly, Daniel (eds.) (2015). "Alosa alosa" in FishBase. April 2015 version.
- . Retrieved 18 November 2021.
- ^ "Allis shad: Alosa alosa". NatureGate. Retrieved 14 December 2013.
- ^ a b c d e f g Lochet, A., S. Boutry, and E. Rochard. Estuarine Phase during Seaward Migration for Allis Shad Alosa Alosa and Twaite Shad Alosa Fallax Future Spawners. Ecology of Freshwater Fish 18 (2009): 323-35.
- ^ 77.5 (2010): 1137-149.
External links
- Data related to Alosa alosa at Wikispecies
- EU LIFE-Project: The re-introduction of allis shad (Alosa alosa) in the Rhine system
- New International Encyclopedia. 1905. .