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Geology topics

J. L. Curnutt

Publications and source records attributed to J. L. Curnutt.

3 recordsLinked to original sources

Landscape-based spatially explicit species index models for everglades restoration

As part of the effort to restore the ∼10 000-km 2 Everglades drainage in southern Florida, USA, we developed spatially explicit species index (SESI) models of a number of species and species groups. In this paper we describe the methodology and results of three such models: those for the Cape Sable Seaside Sparrow and the Snail Kite, and the species group model of long-legged wading birds. SESI models are designed to produce relative comparisons of one management alternative to a base scenario or to another alternative. The model outputs do not provide an exact quantitative prediction of future biotic group responses, but rather, when applying the same input data and different hydrologic plans, the models provide the best available means to compare the relative response of the biotic groups. We compared four alternative hydrologic management scenarios to a base scenario (i.e., predicted conditions assuming that current water management practices continue). We ranked the results of the comparisons for each set of models. No one scenario was beneficial to all species; however, they provide a uniform assessment, based on the best available observational information, of relative species responses to alternative water-management plans. As such, these models were used extensively in the restoration planning.

Florida

Bald eagle nest site characteristics in South Florida

Florida had nearly 20% of the coterminous United States population of nesting bald eagles ( Haliaeetus leucocephalus ) in 1990 (U.S. Fish and Wildl. Serv. 1991), yet the nesting ecology of bald eagles in subtropical environments has not been investigated. We examined nest site selection (n = 156 sites) by bald eagles in Florida Bay, Florida, from 1959 to 1990. Black ( Avicennia germinans ) and red mangroves ( Rhizophora mangle ) were used as nest trees almost exclusively (96.9%), and more than half were snags. Eagles also built nests on the ground (n = 3) and raised young on the ground after nests collapsed (n = 5). Eagles preferred (P < 0.05) higher keys (grass, hardwood-buttonwood [ Conocarpus erecta ]) over low-lying keys (mangrove, marsh) for nesting. Management strategies should include the preservation of live and dead mangroves and large, undisturbed keys as potential nesting sites for bald eagles in the subtropical portion of the eagle's range.

Florida