1. FW 479: Tournament Lit Review - 2
11/16/2019
Dispersal of Tournament Caught Black Bass
Gene R. Wilde
2003
Fisheries
Presented by: Brian Kiely

2. FW 479: Tournament Lit Review - 2
11/16/2019
Location of Study
Review of previous research
12 studies of dispersal of tournament caught fish
Conducted from
Throughout CONUS
Studies examined ranged from 36 days to 2.5 years in length and examined dispersal of 5 to 4,323 fish

3. FW 479: Tournament Lit Review - 2
11/16/2019
Major Questions
What proportion of fish return to capture sights?
What is the rate and distance dispersed?
Does dispersal differ among LM and SM bass?

4. FW 479: Tournament Lit Review - 2
11/16/2019
Major Questions
Does dispersal differ between lake and river-caught fish?
What proportion of dispersing fish are recaptured?

5. FW 479: Tournament Lit Review - 2
11/16/2019
Major Findings
Black bass rarely return to the site of capture
Possible effects of tournament handling?
Distance dispersed is greater in SM than LM bass
A: Averaged findings
51% and 26% of LM and SM bass, respectively remained within 1.6 km of their release sites
14% and 32% of LM and SM bass, respectively returned to their capture site
23% of tournament caught black bass die after release
For LMB, probability of return is inversely related to distance displaced (Ridgeway 2002)
B: Mean distances dispersed by species
LMB: 1.2 to 9.3 km
SMB: 4 to 9.5 km
Currently, no viable theory has been present to explained the the greater dispersal distance observed for SMB

6. FW 479: Tournament Lit Review - 2
11/16/2019
Major Findings
No evidence for different dispersal rates in lakes vs. rivers
Recapture rates were high for both species
No significant interspecies difference
A: Two-way ANOVA found no evidence of varying dispersal in lakes vs. rivers (P=0.1443)
B: Average recapture rate
LMB: 21.9%
SMB: 14.5%
These estimates are conservative because they are based on tag returns and do not account for tag loss, angler non-reporting, and delayed mortality
Despite higher proportion of LMB being recaptured, the difference between species was not significant (P=0.3936)

7. FW 479: Tournament Lit Review - 2
11/16/2019
Major Findings
Some individuals feed immediately after release
Anglers often exploit concentrations of tournament caught black bass A:
Some researchers suggest that tournament caught black bass may been susceptible to recapture because they are concentrated around release sites which stresses food resources, thus making them more aggressive B:
Numerous studies suggest that most recaptured black bass are caught by participants in subsequent tournaments.

8. FW 479: Tournament Lit Review - 2
11/16/2019
Recommendations
A predictive model of the dispersal process is needed
Studies to predict fishery benefits from better holding and handling of tournament caught fish
Studies of dispersal should be on the same scale as those over which fish are dispersed B:
Improvements in holding and handling could decrease tournament associated mortality
Release practices should be improved
In reservoirs with steep banks, fish are often released through long pieces of PVC pipe

9. FW 479: Tournament Lit Review - 2
11/16/2019
Recommendations
Studies should population effects of recapture of tournament caught fish
Tournament organizers and participants should heed the recommendations of researchers!

10. FW 479: Tournament Lit Review - 2
11/16/2019
Questions?