Fire and Flooding Effects on the Habitat of the Cape Sable Seaside Sparrow

Snyder, James

The Cape Sable seaside sparrow (CSSS) is a federally listed endangered species whose range is entirely within Everglades National Park and Big Cypress National Preserve. Its preferred nesting habitat is the short-hydroperiod grassland known as marl or muhly (for Muhlenbergia filipes) prairie found on either side of the Shark River and Taylor Sloughs (U.S. Fish and Wildlife Service 1999). Recent concerns stem from population declines brought about by prolonged flooding in the sparrow range west of Shark Slough {Walters, et al. 1999). Sparrow habitat requires periodic fire to prevent the encroachment of hardwoods (Curnutt et al. 1998) and prescribed burning is also recommended to prevent large wildfires from denuding significant portions of the critical habitat, fires that would most likely occur during the breeding season (Snyder 1991). The suitability of these short-hydroperiod prairies as sparrow habitat improves with time post-bum for at least four to ten years (U.S. Fish and Wildlife Service 1999, Curnutt et al. 1998). Taylor (1983) suggested that rate of recovery of sparrow populations after burning and sparrow density are higher on more productive sites. While fire is a natural and necessary phenomenon in marl prairies, the interaction of fire and flooding can have profound effects on vegetation structure and composition (Olmsted and Loope 1984; Herndon et al. 1991 ). Fire followed by flooding can result in high levels of mortality of plants that normally resprout vigorously. We propose to document the development of habitat structure following fire at several sites within the range of the CSSS and to examine the interaction of fire and flooding in the recovery of postburn vegetation.