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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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This content will become publicly available on September 1, 2026
Between a Dry Marsh and a Salty Place: Estuarine Habitat Suitability for a Freshwater Fish (Florida Bass) and Implications for Ecosystem Restoration and Climate Change
Numerous species face redistribution and compression of habitat due to climate change. Compounded with anthropogenic stressors, coastal systems are among those experiencing the largest shifts in distribution and degradation of habitats. We coupled long-term movement and environmental data to assess how a freshwater species responds to changes in a coastal refuge habitat to quantify distributional changes, identify key environmental variables, and provide restoration targets. Salinity, variation in salinity, and stage of surrounding marsh habitat were the most important variables driving Florida bass (Micropterus salmoides) occurrence in the estuary. Salinity below 8.7 ppt had the largest positive effect on Florida bass occurrence, while low levels of daily variation in salinity (< 1.3 SD) and marsh stages between 11.4 and 27.7 cm were associated with an increased probability of Florida bass occurrence. Years with above average freshwater inputs that shifted mesohaline boundaries downstream generated 15.3 km2 of both core and conditional habitat for Florida bass, average conditions generated 4.4 km2 of core and conditional habitat, whereas dry conditions compressed Florida bass habitat to 1.7 km2. These results suggest that varying environmental scenarios can shift the amount of suitable habitat available for freshwater species using conditional coastal habitats. Our study provides salinity and marsh depth thresholds that offer actionable management targets to maximize the presence of Florida bass in coastal rivers, with population and fishing quality benefits. Climate change will likely result in large-scale reductions of critical dry season habitat for these species, while restoration efforts and adaptive management can bolster the resiliency of these habitats.
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- PAR ID:
- 10643727
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Estuaries and Coasts
- Volume:
- 48
- Issue:
- 5
- ISSN:
- 1559-2723
- Subject(s) / Keyword(s):
- Habitat suitability Habitat compression Climate change Management thresholds Acoustic telemetry Florida bass
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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