Reproductive biology of trout in a thermally enriched environment: the Firehole River of Yellowstone National Park. Final report, April 1974--June 30, 1978

Technical Report · Fri Jun 30 04:00:00 EDT 1978

OSTI ID:6892999

Kaya, C M

Trout in the warmest section of the Firehole River live at temperatures averaging 10.5 C higher than those in the upstream, coldwater sections. Reproduction of brown and rainbow trout are affected in different ways by residence in the warmest part of the river; brown trout have poor reproductive success, while rainbow trout reproduce successfully but have their spawning period shifted to late fall. This change in spawning time appears to be an adaptation to avoid the high temperatures which would prevail during the spring to early summer spawning period typical for this species in this geographical area. After acclimation to temperatures ranging from 5 to 24.5 C, fingerling and juvenile rainbow trout from the Firehole River had median resistance times to high temperatures and upper incipient lethal temperatures similar to those of two hatchery strains of rainbow trout. Reproduction of rainbow trout in the lower Firehole River thus does not appear to be dependent on, or accompanied by, an adaptation of increased tolerance to high summer temperatures. Both species grow considerably faster at the warm-water stations than they do at the cold-water stations, despite having their growth inhibited by high summer temperatures. Differences in diet are evident, with Trichoptera, Ephemeroptera, and Plecoptera being numerically the most important food items for trout at the cold-water stations, and snails of the genus Physa, Diptera, and Ephemeroptera most important for both species in the warmest section.

• Research Organization: Montana State Univ., Bozeman (USA). Dept. of Biology
• OSTI ID: 6892999
• Report Number(s): RLO-2228-T2-4
• Country of Publication: United States
• Language: English

Related Subjects

520400 -- Environment
Aquatic-- Thermal Effluents Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
560205* -- Thermal Effects-- Vertebrates-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMALS
AQUATIC ORGANISMS
BIOLOGICAL ADAPTATION
DIET
FISHES
PUBLIC LANDS
REPRODUCTION
TEMPERATURE DEPENDENCE
TEMPERATURE EFFECTS
THERMAL WATERS
TROUT
VERTEBRATES
YELLOWSTONE NATIONAL PARK