Food Consumption of Juvenile Coho (Oncorhynchus kisutch) and Chinook Salmon (O. tshawytscha) on the Continental Shelf off Washington and Oregon

Abstract

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.

In situ determination of food daily ration in fish: review and field evaluation

“…Food daily ration can be determined completely from laboratory experiments (Walh & Stein 1991), from in situ experiments (Thorpe 1977, Boisclair & Leggett 1985,1988,1989, Garcia & Adelman 1985, Kolok & Randorf 1987, Booth 1990, Sagar & Glova 1988, Walsh et al 1988, and often with a combination of both approaches (e.g. daily variations of food content weight determined in the field and food evacuation rate estimated in laboratory; Swenson 1977, Godin 1981, Brodeur & Pearcy 1987, Amundsen & Klemetsen 1988, Ruggerone 1989, Brodeur et al 1992). …”

Ecology of Juvenile Salmon in Shallow Tidal Freshwater Habitats of the Lower Columbia River, 2007?2010

“…Although the physiological response of a salmon is known to vary with ontogeny (Brett 1995), we feel the application of this model is appropriate. Previous research has found model-predicted estimates of consumption by juvenile salmon to be within 10% of field and laboratory estimates derived independently (Beauchamp et al 1989;Brodeur et al 1992;Ruggerone and Rogers 1992).…”

“…Although this model was developed originally for adult Chinook salmon, previous research has found model-predicted estimates of consumption by juvenile salmon to be within 10% of independently generated field and laboratory estimates (Beauchamp et al 1989;Brodeur et al 1992;Ruggerone and Rogers 1992). Thus, the model is appropriate for the analysis of juvenile Chinook salmon energetics.…”

Integrating dynamic energy budget (DEB) theory with traditional bioenergetic models

“…Aydin et al, 2005;Ballantyne et al, 2003;Beauchamp et al, 2004;Brodeur et al, 1992;Cech and Myrick, 1999;Madenjian et al, 2004;Petrell and Jones, 2000;Stewart and Ibarra, 1991) are often limited to a particular size range of individuals and to a particular species. However, to fully understand the cumulative impact of stressors at different life stages, and how management and restoration actions could impact salmon populations, we need tools that connect the different life stages and their environments.…”