Nekton in the northern Gulf of Mexico often depend on marsh habitat and estuarine nursery areas during their life history, but patterns of habitat use and the underlying processes that drive these patterns are not fully understood. We examined small-scale (1-50 m) patterns of habitat use in Barataria Bay, Louisiana, between 2002 and 2006 by collecting nekton with a 1-m2 drop sampler. Habitat-specific densities were estimated for six habitat types at various distances from the shoreline into the marsh (Marsh1M = 1m and Marsh3M = 3 m into the marsh) and over shallow nonvegetated bottom, SNB (SNB1M = 1 m, SNB5M = 5 m, SNB20M = 20 m, and SNB50M = 50 m) seaward of the marsh. Habitat-specific growth rates also were estimated for brown shrimp Farfantepenaeus aztecus caged in SNB1M, SNB5M, and SNB20M. Nekton density patterns in Barataria Bay appeared to be clearly different from the Galveston Bay model, which predicts nekton distribution patterns relative to the marsh shoreline. Although densities in Barataria Bay were significantly higher in samples near the marsh shoreline (Marsh1M or SNB1M) for brown shrimp, blue crab, and white shrimp, highest mean densities were not always present in marsh edge vegetation. In addition, densities of brown shrimp and white shrimp in Barataria Bay declined much more steeply with distance into the marsh than in the model. Daily growth rates (1.0 - 1.2 mm TL day-1; 68 - 89 mg day-1) for brown shrimp were similar among SNB habitat types. Our results suggest that SNB in Barataria Bay may be relatively more important as habitat for fishery species than previously assumed.

Patterns of habitat utilization were compared among transplanted and natural Spartina alterniflora marshes in the Halls Lake area of Chocolate Bay in the Galveston Bay estuary, and East Matagorda and Corpus Christi Bay systems along the lower Texas coast to test the null hypothesis that transplanted marshes along the Texas coast were equivalent to natural marshes.

Sampled marshes and ponds along two transects within the intermediate and brackish marsh zones of Breton Sound, Louisiana, from May 7-11, 2001. Sampling followed several planned releases of freshwater from the Caernarvon diversion structure during the winter of 2000 and spring of 2001 as part of a larger study to examine the ecological effect of pulsed freshwater releases on the ecosystem.

This data set contains sensitive biological resource data for marine, estuarine, anadromous, and freshwater fish species in Columbia River. Vector polygons in this data set represent locations of fish distribution, concentration areas, spawning areas, and salmon spawning runs. Species specific abundance, seasonality, status, life history, and source information are stored in relational data tables (described below) designed to be used in conjunction with this spatial data layer.This data set comprises a portion of the Environmental Sensitivity Index (ESI) data for Columbia River. ESI data characterize the marine and coastal environments and wildlife by their sensitivity to spilled oil. The ESI data include information for three main components: shoreline habitats, sensitive biological resources, and human-use resources. See also the FISHL (Fish Lines) data layer, part of the larger Columbia River ESI database, for additional fish information.