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In South Florida, the allocation of the limited freshwater supply is of constant debate. Stakeholder groups for freshwater include agriculture, South Florida populations, and the natural environment and the ecosystem services that they provide. One ecosystem service invaluable to South Florida is the provisioning of coastal recreational fisheries. This ecosystem service generates approximately 8 billion dollars in angler expenditures in Florida alone. However, the interplay between the provisioning of fisheries and the allocation and input of freshwater to coastal systems is largely unknown. One such way that recreationally important fishes could be impacted by changes in freshwater inputs to coastal systems is through the availability of food. Previous research has shown that seasonal rainfall patterns and freshwater management create spikes in prey availability for important recreational fishes such as Common Snook (Centropomus undecimalis) and Largemouth Bass (Micropterus salmoides). These prey pulses are restricted to the most inland reaches of the estuary. However, two important questions remain unanswered: 1) How far away do snook and bass move to take advantage of this prey subsidy? 2) Do these spikes in prey availability increase the reproductive output of snook? In order to answer these questions, we use acoustic telemetry to track the movements of key recreational fish species (Common Snook and Largemouth Bass) over multiple years (2012 – current) in the Shark River Estuary, Everglades National Park. Data provided by this study will be the first step in quantifying the importance of freshwater inflows to coastal fisheries. From a science perspective our research will provide valuable insight to how highly mobile species respond to pulses of prey across a patchy landscape, and how these temporary highly abundant resources will act to boost consumer populations. The value of pulsed resources to consumers have been identified as an important information gap in population ecology.
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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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