Genetic Control in Lakeward Migrations of Cutthroat Trout Fry
- 1 January 1971
- journal article
- Published by Oxford University Press (OUP) in Transactions of the American Fisheries Society
- Vol. 100 (1) , 33-40
- https://doi.org/10.1577/1548-8659(1971)100<33:gcilmo>2.0.co;2
Abstract
Cutthroat trout (Salmo clarki) in Yellowstone Lake spawn in the inlets or in the outlet, Yellowstone River. Fry from natal gravels in inlets move downstream to the lake rearing area while most fry from the outlet move upstream to the lake. We examined the roles of temperature, water source, and innate control in directing migrations of fry. We collected fertilized eggs from cutthroat in an inlet and the outlet of Yellowstone Lake, and incubated them under identical environmental conditions at Jackson, Wyoming. Our test facility on the shore of Yellowstone Lake consisted of three simulated stream sections 14.6 m long, 0.3 m wide, and 6.3 cm deep with a trap at each end. We controlled water temperature with a heater and coolers, and could test fish in pumped lake or stream water. We introduced fry at dusk at the mid‐point of the stream sections, and counted fish which moved upstream or downstream within 12 hours. We kept environment and handling procedures identical during the tests for lots of inlet and outlet fry. The source of acclimation water did not significantly affect direction of migration of fry from either inlet or outlet populations when tested with lake water. Water temperature significantly altered ratios of outlet fry moving upstream and downstream but did not affect direction of movement of inlet fry. We concluded that upstream and downstream migrations by cutthroat fry from inlet and outlet populations were largely controlled by innate responses to environmental stimuli. Our work and other recent studies indicate that the specifically and racially different migration patterns of emergent salmonid fry (Oncorhynchus nerka, Salmo gairdneri and S. clarki) from natal gravels to rearing areas embody genetic‐environmental interactions. Failure by resource managers to match innately‐controlled migration characteristics of a donor population to the requirements of the new environment may explain some unsuccessful attempts to transplant fish.This publication has 0 references indexed in Scilit: