Publications

The coastal red mangrove, Rhizophora mangle L., was introduced to the Hawaiian Islands from Florida 100 yr ago and has spread to cover many shallow intertidal shorelines that once were unvegetated mudflats. We used a field survey approach to test whether mangroves at the land-ocean interface could indicate watershed inputs, especially whether measurements of leaf chemistry could identify...

We presume that the shovelnose sturgeon (Scaphirhynchus platorynchus) has evolved to spawn in the springtime when environmental conditions are at some optimum, but this state has not yet been defined. In this study physiological readiness to spawn in shovelnose sturgeon was examined to define more closely when spawning could occur and thus identify and evaluate prevailing environmental...

Two in-situ exposure studies were conducted with the federally-listed endangered Rio Grande silvery minnow (Hybognathus amarus). One-year-old adults were exposed in cages deployed at three sites in the Middle Rio Grande, N. Mex., for 4 days to assess survival and for 26 days to evaluate survival, growth, overall health, and whole-body elemental composition. The test sites were located on...

The sediments in the Calcasieu Estuary are contaminated with a wide variety of chemicals of potential concern (COPCs), including heavy metals, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, phthalates, chlorinated benzenes, and polychlorinated dibenzo-p-dioxins and dibenzofurans. The sources of these COPCs include both point and non-point source discharges. As part of a...

A remedial investigation/feasibility study (RI/FS) of the Calcasieu Estuary cooperative site was initiated in 1998. This site, which is located in the southwestern portion of Louisiana in the vicinity of Lake Charles, includes the portion of the estuary from the saltwater barrier on the Calcasieu River to Moss Lake. As part of the RI/FS, a baseline ecological risk assessment (BERA) was...

No abstract available.

Many National Wildlife Refuges (Refuges) have impaired water quality resulting from historic and current land uses, upstream sources, and aerial pollutant deposition. Competing duties limit the time available for Refuge staff to identify and evaluate potential water quality issues. As a result, water quality–related issues may not be resolved until a problem has already arisen. This...

The Floristic Quality Index (FQI) has been used as a tool for assessing the integrity of plant communities and for assessing restoration projects in many regions of the USA. Here, we develop a modified FQI (FQImod) for coastal Louisiana wetlands and verify it using 12 years of monitoring data from a coastal restoration project. Plant species that occur in coastal Louisiana were assigned...

No abstract available.

The implementation of freshwater diversions in large-scale coastal restoration schemes presents several scientific and management considerations. Large-scale environmental restructuring necessitates aquatic biomonitoring, and during such field studies, photographs that document animals and habitat may be captured. Among the biomonitoring studies performed in conjunction with the Davis...

The Meramec River Basin in east-central Missouri is an important stronghold for native freshwater mussels (Order: Unionoida) in the United States. Whereas the basin supports more than 40 mussel species, previous studies indicate that the abundance and distribution of most species are declining. Therefore, resource managers have identified the need to prioritize threats to native mussel...

Amphibians are a diverse group of animals that includes frogs, toads, and salamanders. They are adapted to living in a variety of habitats, but most require water for at least one life stage. Amphibians have recently become a worldwide conservation concern because of declines and extinctions even in remote protected areas previously thought to be safe from the pressures of habitat loss...