The influence of fall-spawning salmon on growth and production of juvenile coho salmon rearing in beaver ponds on the Copper River Delta, Alaska

This thesis examined the influence of fall-spawning coho salmon on the
density, growth rate, body condition, and survival to outmigration of juvenile coho
salmon rearing in beaver ponds on the Copper River Delta, Alaska. During the fall of
1999 and 2000 fish rearing in ponds that received spawning salmon were compared to
ponds that did not receive spawners, and to ponds that were artificially enriched with
salmon carcasses and eggs. Juvenile coho salmon responded variably to fall-spawning
salmon. There were no consistent patterns associated with the two naturally occurring
pond types (spawning vs no spawning). In some ponds, fall-spawning salmon
increased growth rates and improved the body condition of juvenile coho salmon.
Enrichment with salmon carcasses and eggs significantly increased growth rates of
fish in non-spawning ponds. For some ponds, the relative influence of spawning and
enrichment on body condition depended on fish size. There was no evidence that the
influence of fall-spawning resulted in greater smolt production. Fall-spawning salmon
provide important food resources that can benefit juvenile coho salmon rearing in
beaver ponds on the Copper River Delta. However, other factors such as nutrients
from riparian vegetation and catchment characteristics that control hydrology and
thermal regimes are important to coho salmon smolt production. / Graduation date: 2004

Identiferoai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/30820
Date13 June 2003
CreatorsLang, Dirk W.
ContributorsReeves, Gordon H.
Source SetsOregon State University
Languageen_US
Detected LanguageEnglish
TypeThesis/Dissertation

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