Back Hypomesus transpacificus CEB Hypomesus transpacificus German Hypomesus transpacificus Basque سیمینماهی دلتا Persian Hypomesus transpacificus French Hypomesus transpacificus Dutch Тихоокеанская корюшка Russian Hypomesus transpacificus Serbian 越洋公魚 Chinese
| Delta smelt | |
|---|---|
| |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Osmeriformes |
| Family: | Osmeridae |
| Genus: | Hypomesus |
| Species: | H. transpacificus
|
| Binomial name | |
| Hypomesus transpacificus McAllister, 1963
| |
The delta smelt (Hypomesus transpacificus) is an endangered[1] slender-bodied smelt, about 5 to 7 cm (2.0 to 2.8 in) long, in the family Osmeridae. Endemic to the upper Sacramento-San Joaquin Estuary of California, it mainly inhabits the freshwater-saltwater mixing zone of the estuary, except during its spawning season, when it migrates upstream to fresh water following winter "first flush" flow events (around March to May).[4] It functions as an indicator species for the overall health of the Delta's ecosystem.[5]
Because of its one-year lifecycle and relatively low fecundity, it is very susceptible to changes in the environmental conditions of its native habitat.[6] It is listed as a federally threatened species under the Endangered Species Act of 1973.[2][3][7] Efforts to protect the fish from further decline and extinction have focused on limiting or modifying the large-scale pumping activities of state and federal water projects at the southern end of the estuary, thereby limiting water available to farming. However, these efforts have not prevented the species from becoming functionally extinct in the wild.[8]
- ^ a b NatureServe (2020) [errata version of 2014 assessment]. "Hypomesus transpacificus". IUCN Red List of Threatened Species. 2014: e.T10722A174778740. doi:10.2305/IUCN.UK.2014-3.RLTS.T10722A174778740.en. Retrieved 7 May 2023.
- ^ a b "Delta smelt (Hypomesus transpacificus)". Environmental Conservation Online System. U.S. Fish & Wildlife Service. Retrieved 7 May 2023.
- ^ a b 58 FR 12854
- ^ Sommer, T. et al. 2011. The spawning migration of delta smelt in the Upper San Francisco Estuary. San Francisco Estuary and Watershed Science: 9(2).
- ^ "Delta Smelt". Center for Biological Diversity. Retrieved 10 May 2015.
- ^ Moyle, PB. 2002. Inland fishes of California. University of California Press, Berkeley.
- ^ Cite error: The named reference
USFWSwas invoked but never defined (see the help page). - ^ Cite error: The named reference
Kriegerwas invoked but never defined (see the help page).