Delta Smelt fin) Sitsatopthebackbetweendorsal Deltasmeltarefoundonlyinthesacramento- Threatened,Listedmarch5,1993
Endangered SpecU.S. Environmental iesFacts Protection Agency Delta Smelt Hypomes us transpacificus Description and Ecology Status Threatened, listed March 5, 1993. large geographic area such as Suisun Bay, which has shoals, sloughs, wetland edges, and suitable spawning substrate at Critical Habitat Designated December 19, 1994. depths less than 13 feet. Low outflows keep adult delta smelt Appearance The delta smelt typically grows to 2.4–2.8 and their larvae upstream in the deep, narrow channels of inches in length. Except for the steel-blue sheen on its sides, the rivers and delta, where food production is limited by the Photo source: B. Moose Peterson/USFWS Digital Library its delicate, slender body appears nearly transparent. Its eyes inability of sunlight to penetrate water depths. appear large. Its relatively small mouth has little, pointed Reproduction and Life Cycle While spawning teeth on the upper and lower jaws. A small, fl eshy fi n (adi- can occur from January through July, low outfl ow tends The delta smelt is a threatened pose fin) sits atop the back between the dorsal fin and the to eclipse the season from March to mid-May. Spawning species. Threatened species tail. are plants and animals whose occurs in sloughs and shallow, edge-waters of channels in Range Delta smelt are found only in the Sacramento- population numbers are so the upper Delta. Each female broadcasts 1,200–2,600 eggs. San Joaquin estuary in California. Historically, populations Eggs sink to the bottom and adhere to rocks, gravel, tree low that they may become were found from Suisun Bay, east to the Delta area, and roots, and submerged vegetation or branches.
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