Long-term captive breeding does not necessarily prevent reestablishment: lessons learned from Eagle Lake rainbow trout |
| |
Authors: | Gerard Carmona-Catot Peter B Moyle Rachel E Simmons |
| |
Institution: | (1) Department of Wildlife, Fish and Conservation Biology, University of California, Davis, Davis, 95616, CA, USA;(2) Institute of Aquatic Ecology, University of Girona, 17071 Girona, Catalonia, Spain;(3) Department of Animal Science, Genomic Variation Lab, University of California, Davis, Davis, 95616, CA, USA |
| |
Abstract: | Captive breeding of animals is often cited as an important tool in conservation, especially for fishes, but there are few
reports of long-term (<50 years) success of captive breeding programs, even in salmonid fishes. Here we describe the captive
breeding program for Eagle Lake rainbow trout, Oncorhynchus mykiss aquilarum, which is endemic to the Eagle Lake watershed of northeastern California. The population in Eagle Lake has been dependent
on captive breeding for more than 60 years and supports a trophy fishery in the lake. Nevertheless, the basic life history,
ecological, and genetic traits of the subspecies still seem to be mostly intact. Although management has apparently minimized
negative effects of hatchery rearing, reestablishing a wild population would ensure maintenance of its distinctive life history
and its value for future use as a hatchery fish. An important factor that makes reestablishment possible is that the habitat
in Eagle Lake is still intact and that Pine Creek, its major spawning stream, is recovering as habitat. With the exception
of an abundant alien brook trout (Salvelinus fontinalis) population in Pine Creek, the habitat factors that led to the presumed near-extinction of Eagle Lake rainbow trout in the
early twentieth century have been ameliorated, although the final stages of reestablishment (eradication of brook trout, unequivocal
demonstration of successful spawning migration) have still not been completed. The Eagle Lake rainbow trout story shows that
long-term captive breeding of migratory salmonid fishes does not necessarily prevent reestablishment of wild populations,
provided effort is made to counter the effects of hatchery selection and that natural habitats are restored for reintroduction.
Long-term success, however, ultimately depends upon eliminating hatchery influences on wild-spawning populations. Extinction
of Eagle Lake rainbow trout as a wild species becomes increasingly likely if we fail to act boldly to protect it and the Eagle
Lake watershed. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|