Food Consumption of Juvenile Coho (Oncorhynchus kisutch) and Chinook Salmon (O. tshawytscha) on the Continental Shelf off Washington and Oregon
| Autor: | William G. Pearcy, Robert C. Francis, Richard D. Brodeur |
|---|---|
| Rok vydání: | 1992 |
| Předmět: |
geography
Food intake Chinook wind geography.geographical_feature_category biology Continental shelf Food consumption Aquatic Science Seasonality biology.organism_classification medicine.disease Pacific ocean Fishery medicine Environmental science Oncorhynchus Juvenile Ecology Evolution Behavior and Systematics |
| Zdroj: | Canadian Journal of Fisheries and Aquatic Sciences. 49:1670-1685 |
| ISSN: | 1205-7533 0706-652X |
| Popis: | The overall food consumption by juvenile coho (Oncorhychus kisutch) and chinook salmon (O. tshawytscha) along the continental shelf off Washington and Oregon was estimated for the summer months of 1981–84 using both a direct field and indirect bioenergetic approach. Both models yielded similar estimates but the consumption estimated by the bioenergetic model was 14.8 and 3.2% higher for coho and chinook salmon, respectively. In a given year, overall consumption increased throughout the summer, despite decreasing abundances of both salmon species, but there were substantial differences among the four years within the same month. A preliminary comparison of the consumption estimates for important prey taxa early in the summer with estimated zooplankton biomass suggested that sufficient food levels may have been available for salmon during 1981. During the El Niño of 1983, however, several prey groups were consumed at high levels relative to their estimated availability and the biomass of these taxa may not have been sufficient to sustain the total population of salmon. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|