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Abstract Catch‐and‐release (C&R) angling is often used to maintain high catch rates but fish vulnerability to capture may decrease following hooking, thereby decreasing angler catch per unit effort (CPUE) (hyperdepletion). To determine if fish post‐capture response affected recapture probability and population‐level CPUE, individual capture histories of Largemouth Bass in two lakes were compared before and after doubling angling effort in a Before‐After Control‐Impact (BACI) analysis. Previous capture and day‐of‐season both affected recapture probability. Counteracting effects of previous capture and reduced late‐season catch rates caused no hyperdepletion of angler CPUE. Our results highlight the complexity of fish behavioral responses to angling and suggest that hyperdepletion of angling catch rates may not be an issue in C&R fisheries.
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Survival of Florida Largemouth Bass in a Coastal Refuge Habitat across Years of Varying Drying Severity
Abstract In aquatic systems, refuge habitats increase resistance to drying events and maintain populations in disturbed environments. However, reduced water availability and altered flow regimes threaten the function of these habitats. We conducted a capture–mark–recapture study, integrating angler citizen science. Our objectives were to quantify variation in survival of Florida Largemouth BassMicropterus salmoides floridanusin a coastal refuge habitat across seasonal hydrological periods and over 4 years of varying drying severity and to determine the contribution of angler sampling to improving capture probabilities. Apparent survival of Florida Largemouth Bass in the coastal Everglades was highest in wet and drying periods and lowest in dry and reflooding periods. Interannual survival was closely tied to the length of upstream marsh drying, with the lowest observed survival (0.21) during a drought year. The inclusion of angler sampling improved recapture probabilities, suggesting that angler data can supplement standardized electrofishing sampling. Findings show that during short drying events Florida Largemouth Bass survival can be relatively high, with implications for Everglades restoration. Understanding the ability of refuge habitats to buffer populations from drying disturbance is a key component for conservation and restoration, particularly under climate change scenarios.
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- PAR ID:
- 10449285
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Transactions of the American Fisheries Society
- Volume:
- 150
- Issue:
- 4
- ISSN:
- 0002-8487
- Format(s):
- Medium: X Size: p. 435-451
- Size(s):
- p. 435-451
- Sponsoring Org:
- National Science Foundation
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