1 Movements, Home Range, and Survival Estimation of Largemouth Bass following Displacement Author - Mark S. Ridgway Name of Journal - American Fishery Society Year Brian Elkington

2 Questions Addressed Effects of “tournament style” displacement on: Movements Home range Survival

3 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

4 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”

5 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

6 Bass Distribution of Displacement

7 Findings Home Range Experiments: Home Range area size did not differ between 1996 – 1998 captured bass

8 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.

9 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

10 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