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Movements, Home Range, and Survival Estimation of Largemouth Bass following Displacement. Author - Mark S. Ridgway . Name of Journal - American Fishery Society Year - 2002 Brian Elkington. Questions Addressed. Effects of “tournament style” displacement on: Movements Home range
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Movements, Home Range, and Survival Estimation of Largemouth Bass following Displacement Author - Mark S. Ridgway Name of Journal - American Fishery Society Year - 2002 Brian Elkington
Questions Addressed • Effects of “tournament style” displacement on: • Movements • Home range • Survival
Location and Methods • Rideau Lake, Ontario • Mean depth-13.3m • Study was carried out over 1996, 1997, 1998 • Utilized radio and ultrasonic tags to determine movements • Fish were collected using hook and line, 55 fish total
Methods • 27 fish were used for movement studies • 27 fish were used for survival studies • Movement studies displaced bass from 1.5 to 16.5 km • Survival analysis was done with the “Know Fate Model”
Findings • Movement Experiments: • 8 of 27 lost to anglers during study • Only 37% of total displaced bass returned to their capture site. • No bass traveled more then 8km • In one week bass moved approx. 200m • In two weeks they moved approx. 458m
Findings • Home Range Experiments: • Home Range area size did not differ between 1996 – 1998 captured bass
Findings • Survival Experiments: • Overall probability of surviving the fishing season, S=0.587 • Survival studies indicate increased pressure over holiday weekends • 71.7% of all annual mortality occurs in the fishing season.
Authors Discussion • Return to original home range was low, only 7 of 27. • Some bass took up to a year to return. • Increased angling mortality during the first half of the season. • Vulnerability of bass released in large groups may vary
Authors Discussion • Multiple tournaments on one lake would change his findings. • Different stresses may occur in a tournament setting • More studies need to be made to investigate the survival of bass