Publications

No abstract available.

No abstract available.

In 1978 biologists in Gainesville, Florida, began compiling records on the distribution and status of nonindigenous fishes known in U.S. inland waters. The database, now in electronic format, currently contains approximately 17,000 records representing more than 500 nonindigenous fish taxa (i.e., species, hybrids, and unidentified forms). Of these taxa, 317 (61%) are native to the United...

Metazoan parasites and commensals were collected from dead manatees salvaged in Puerto Rico. Thirty-five manatees were examined between 1980 and 1998. Parasites and commensals were identified in 20 (57%) manatees and included 3 species of helminths, 1 nematode (Heterocheilus tunicatus) and 2 digeneans (Chiorchis fabaceus and Cochleotrema cochleotrema). Two species of commensals were also

Lake Chicot, in south central Louisiana, USA, was created in 1943 by the impoundment of Chicot Bayou. Extensive establishment of woody seedlings occurred in the lake during a 1.5 year period, including the growing seasons of both 1986 and 1987, when the reservoir was drained for repair work on the dam. Study plots were established in September 1986 to document woody vegetation...

We created a model to study the process in which nutria (Myocastor coypus) feeding activities lead to erosion and loss of marsh area. This model ties together data on nutria population dynamics and feeding behavior from the literature with data from field studies on the phenology of Scirpus americanus and Spartina patens conducted in the Barataria Basin, Louisiana, USA in 1992. The...

Ideally, general ecological relationships may be used to predict responses of natural communities to environmental change, but few attempts have been made to determine the reliability of predictions based on descriptive data. Using a previously published structural equation model (SEM) of descriptive data from a coastal marsh landscape, we compared these predictions against observed...

Gulf sturgeon spawn on portions of three sites in the upper Suwannee River, which may appropriately be described as spawning reefs. The same areas are utilized from year to year. Habitat factors important in spawning site determination include gravel/cobble substrate, the presence of eddy fields, a neutral to slightly alkaline pH, and an empirically observed range in calcium ion content...

Aircraft L-band VV-, HH-, and VH-polarizations were examined as tools for monitoring burn recovery in a coastal marsh. Significant relationships were observed between time-since-burn (difference between burn and image collection dates; 550-900 days after burn) and returns related to all polarizations. As marsh burn recovery progressed, VV returns decreased while HH and VH returns...

We describe the development, structure, and corroboration process of a simulation model of animal behavior (MOAB). MOAB can create spatially explicit, individual-based animal foraging models. Users can create or replicate heterogeneous landscape patterns, and place resources and individual animals of a goven species on that landscape to simultaneously simulate the foraging behavior of...

Here we propose that an important cause of variation in species density may be prior environmental conditions that continue to influence current patterns. In this paper we investigated the degree to which species density varies with location within the landscape, independent of contemporaneous environmental conditions. The area studied was a coastal marsh landscape subject to periodic...

Variation of electrochemical oxidation-reduction (redox) potential was examined in surface salt march sediments under conditions of flooding and tidal simulation in mesocosms and field sites. Time series were generated of redox potential measured in sediment profiles at 2-10 cm depth using combination Pt-Ag/AgCl (ORP) electrodes. Redox potential data were acquired at rapid rates (1-55...