Publications

Surface water quality was monitored at 19 stations (2-4 week intervals) in six drainage basins of Big Thicket National Preserve of east Texas between 1996 and 1999. The parameters monitored were temperature, dissolved oxygen, pH, conductivity, current speed, light attenuation, chlorophyll a and concentrations of ammonium, ortho-phosphate, nitrate and nitrite. The best water quality (low...

We developed a key to identify wings of hybrids between American Black Ducks (Anas rubripes) and Mallards (A. platyrhynchos). Material for analysis included review of historical descriptions dating from the late 1700's, older museum collections in Europe and North America, wings collected from hunters in North America and Great Britain, birds banded in Canada and the United States, and a...

No abstract available.

Fire has played an important role in the structure of natural ecosystems throughout North America. As a natural process, fire helps clear away dead and dying plant matter and increases the production of native species that occur in fire prone habitats. It also reduces the invasion of exotic species and the succession to woody species in pitcher plant bogs, pine savannas, coastal prairies...

Louisiana's coast and its degradation and restoration are major environmental issues being studied at the National Wetlands Research Center. Coastal ecosystems are vulnerable because of the tremendous amount of human activity that takes place along the coast. Information on ecological processes is essential to guide the development along the coast as well as to protect and restore...

The USGS National Wetlands Research Center has documented that Seagrasses in the northern Gulf of Mexico constitute an ecosystem in trouble. From studies in St. Andrews Bay, Period Bay, the Chandeleur Islands, and the Gulf Islands National Seashore, scientists have discovered that declining seagrass acreage ranges from 12% to 66% in bays and estuaries of the Gulf of Mexico. Not only are...

St. Vincent National Wildlife Refuge is managed by the U.S. Fish and Wildlife Service (USFWS). The refuge was acquired in 1968 from a private land owner and occupies all of St. Vincent Island, a barrier island located off the southern coast of the Florida Panhandle near Apalachicola (fig. 1). The island, which covers 12,358 acres, is about 9 miles long and 4 miles across at its widest...

An extensive deep (~100 m) reef tract occurs on the Mississippi-Alabama outer continental shelf (OCS). The tract, known as "The Pinnacles", is apparently part of a sequence of drowned reef complexes along the "40-fathom" shelf edge of the northern Gulf of Mexico (Ludwick and Walton, 1957). It is critical to determine the accurate geomorphology of deep-reefs because of their importance as...

No abstract available.

No abstract available.

This project examined the pathways of mercury (Hg) bioaccumulation and its relation to trophic position and hydroperiod in the Everglades. I described fish-diet differences across habitats and seasons by analyzing stomach contents of 4,000 fishes of 32 native and introduced species. Major foods included periphyton, detritus/algal conglomerate, small invertebrates, aquatic insects...

No abstract available.