Feeding Activity, Rate of Consumption, Daily Ration and Prey Selection of Major Predators in John Day Reservoir, 1984 : Annual Report.

Technical Report · Tue Jul 01 04:00:00 EDT 1986

DOI:https://doi.org/10.2172/5498471· OSTI ID:5498471

Gray, Gerard A

The extent of predation on juvenile salmonids in John Day Reservoir was determined. Salmonids were the single most important food item by weight for northern squawfish (Ptychocheilus oregonensis) in the restricted zones at McNary tailrace and John Day forebay during all sampling periods. Salmonids accounted for 18.1% of the weight in the diet of walleyes (Stizostedion vitreum vitreum) in 1984 which was at least twice that found in previous years. In smallmouth bass (Micropterus dolomieui) salmonids contributed little to their diet whereas for channel catfish (Ictalurus punctatus) fish accounted for 64.1% of the weight in their diet with salmonids responsible for approximately half of this weight. An intensive search of the fisheries literature was conducted to review various fish capture and control techniques which might have potential as predation control measures for the major predators of juvenile salmonids in the Columbia River system. Most prey protection measures were judged to have high potential and direct predator control measures were judged to have moderate or low potential.

• Research Organization: Fish and Wildlife Service, Cook, WA (USA). Willard Field Station
• DOE Contract Number: AI79-82BP34796
• OSTI ID: 5498471
• Report Number(s): DOE/BP-34796-1; ON: DE86014192
• Country of Publication: United States
• Language: English

Related Subjects

13 HYDRO ENERGY
130600 -- Hydro Energy-- Environmental Aspects
520500* -- Environment
Aquatic-- Site Resource & Use Studies-- (-1989)
54 ENVIRONMENTAL SCIENCES
ANADROMOUS FISHES
ANIMALS
AQUATIC ORGANISMS
COLUMBIA RIVER
CONTROL
DIET
FEDERAL REGION X
FISHES
Fishes - Food - Columbia River
NORTH AMERICA
OREGON
PEST CONTROL
PREDATOR-PREY INTERACTIONS
Predation (Biology)
RIVERS
SALMON
STREAMS
SURFACE WATERS
USA
VERTEBRATES
WATER RESERVOIRS