Various aspects of downstream migratory behavior of sockeye salmon fry (pncorhynchus nerka) were examined in a series of field and laboratory experiments. The field work at the Department of tie Environment (Fisheries and Marine Service) Fulton Eiver spawning channels, Babine Lake, British Columbia, was concerned with the predation by rainbow trout (Salmo gairdneri) and whitefish (Prosopium williamsoni) on sockeye fry with various kinds of prior experience. The laboratory studies focused on the effects of exposure to light on the behavior of emerging and recently emerged fry. The results showed that : (1) the number of fry moving downstream varies throughout the nightly migration period; (2) the presence cf predators modifies the movement pattern of migrating fry, such that the fry tend to move downstream over a more concentrated time period;
(3) fry response to predators
tends not to be predator-specific,
migrating fry respond
similarly to different species of
predators; (4) emergent
fry are not all similar in
their migratory behavior, some tend to migrate rapidly
(fast migrants), while others
migrate at a slower rate
(slow migrants); (5) generally
fry with prior experience to predators displayed
different migratory behavior compared to fast and slow
migrants; and (6) subjecting newly-emerged fry to increasing
time periods of light
treatment and fry densities,
alters behavior patterns. It
is concluded that fry commencing
downstream movement are
not all similar in their migratory
behavior. Begardless of
the basis for the behavioral difference between fast and slow migrants, the presence of predators modifies and enhances downstream movement. Further, subjecting premigratory fry to light, alters downstream movement and behavioral interactions between fry. / Science, Faculty of / Zoology, Department of / Unknown
| Identifer | oai:union.ndltd.org:UBC/oai:circle.library.ubc.ca:2429/21730 |
| Date | January 1979 |
| Creators | Delaney, Peter Wayne |
| Source Sets | University of British Columbia |
| Language | English |
| Detected Language | English |
| Type | Text, Thesis/Dissertation |
| Rights | For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use. |
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