Affiliation:
1. California Department of Fish and Wildlife
Abstract
The Arroyo Chub (Gila orcutti) is a small cyprinid native to coastal drainages of Los Angeles, Orange, Riverside, and San Diego counties. We surveyed the seven drainages historically known to support the species in 2012-2014 and again in 2019 to determine current range and distribution. We compared our results to the most recent species account we could locate (1993). We detected Arroyo Chub in 18 of the 40 streams (45%) and within six of the seven native watersheds in our 2012-2014 surveys, while our 2019 surveys located fish in all of the seven native watersheds. This native species has retreated to the headwaters in most watersheds and the number of populations have declined since the most recent species account. Non-native species, habitat loss, urbanization, water development, flood control, and drought are thought to be the primary causes of this decline.
Publisher
California Fish and Wildlife Journal, California Department of Fish and Wildlife
Reference39 articles.
1. Baskin, J. N. 1974. Final report on the status of the unarmored threespine stickleback (Gasterosteus aculeatus williamsoni), in the upper Santa Clara River, California.
2. Benjamin, A., B. May, J. O’Brien, and A. J. Finger. 2016. Conservation genetics of an urban desert fish, the Arroyo Chub. Transactions of the American Fisheries Society 145:277–286.
3. Bessert, M. L., and G. Orti. 2008. Genetic effects of habitat fragmentation on Blue Sucker populations in the upper Missouri River (Cycleptuse longatus Lesueur, 1918). Conservation Genetics 9:821¬–832.
4. Brown, L. R., C. A. Burton, and K. Belitz. 2005. Aquatic assemblages of the highly urbanized Santa Ana River Basin, California. American Fisheries Society Symposium 47:263¬–287.
5. Castleberry, D. T., and J. J. Cech, Jr. 1986. Physiological responses of a native and an introduced desert fish to environmental stressors. Ecology 67:912–¬918.