Magnitude and Dynamics of Predation on Juvenile Salmonids in Columbia and Snake River Reservoirs, Annual Report of Research, 1989-1990.
Three aspects of predation upon juvenile salmonids in the Columbia River are addressed in this report: (1) Indexing predator consumption. During 1989--1990, two indices of northern squawfish consumption upon juvenile salmonids were developed for use throughout the Columbia River Basin. The direct Consumption Index (CI) is based upon the concept of meal turnover time and takes into account number of salmonids, temperature, total gut content weight and predator weight. A Bioenergetics Index (BI) for consumption indexing was also developed to complement the direct CI. In the BI, growth, consumption, excretion/evacuation and respiration processes are modeled to predict the consumption required to produce an observed growth increment. (2) Studies on predator-smolt dynamics. Northern squawfish consumption data were collected in the McNary Dam tailrace during nine days in July 1988 to improve our understanding of the predator-smolt functional response. (3) Selective predation by northern squawfish. Laboratory and field protocols were developed to evaluate northern squawfish selection and prey vulnerability. Results from laboratory studies suggest that northern squawfish prefer dead over live prey and that descaled prey may be more vulnerable to predation than non-descaled prey. Stressed and unstressed prey were consumed in equal proportions when predation occurred for 6 or 24 h. Physiological and behavioral effects of stress on juvenile salmon are presented. 100 refs., 13 figs., 12 tabs.
- Research Organization:
- US Fish and Wildlife Service
- Sponsoring Organization:
- US Bonneville Power Administration
- DOE Contract Number:
- AI79-88BP91964
- OSTI ID:
- 6074775
- Report Number(s):
- DOE/BP-91964-1; ON: DE91006328
- Country of Publication:
- United States
- Language:
- English
Similar Records
System-Wide Significance of Predation on Juvenile Salmonids in Columbia and Snake River Reservoirs : Annual Report 1992.
System-Wide Significance of Predation on Juvenile Salmonids in the Columbia and Snake River Reservoirs : Annual Report of Research 1991.
Related Subjects
54 ENVIRONMENTAL SCIENCES
PREDATOR-PREY INTERACTIONS
EVALUATION
SALMON
POPULATION DYNAMICS
AQUACULTURE
AQUATIC ECOSYSTEMS
BIOLOGICAL STRESS
COLUMBIA RIVER BASIN
DYNAMIC FUNCTION STUDIES
FOOD CHAINS
JUVENILES
PROGRESS REPORT
SNAKE RIVER PLAIN
ANADROMOUS FISHES
ANIMALS
AQUATIC ORGANISMS
DOCUMENT TYPES
ECOSYSTEMS
FISHES
VERTEBRATES
Fishes - Mortality
550100* - Behavioral Biology
540310 - Environment
Aquatic- Basic Studies- (1990-)