Publications

The Trinity River Basin was among the first 20 hydrologic systems under full inplementation of the National Water Quality Assessment (NAWQA) Program. Planning and analysis of existing information began in 1991. Intensive water-quality data collection began in 1993. As a part of the NAWQA Program, pesticide samples were taken from surface water, ground water, streambed sediment, and...

The U.S. Geological Survey's investigations of the water resources of Texas are conducted in cooperation with the Texas Water Development Board, river authorities, cities, counties, U.S. Army Corps of Engineers, Bureau of Reclamation, International Boundary and Water Commission, and others. Investigations are under the general direction of R.O. Hawkinson, District Chief, Texas District...

The avoidance response of brown trout (Salmo trutta) to mixtures of cadmium, copper, lead, and zinc was determined in water simulating the Clark Fork River, Montana. Effects of acidification on the avoidance response were also evaluated. Tests were conducted in a cylindrical chamber that received reference water at one end and metal-contaminated water at the other; a distinct boundary...

Aerial counts and the number of deaths have been a major focus of attention in attempts to understand the population status of the Florida manatee (Trichechus manatus latirostris). Uncertainties associated with these data have made interpretation difficult. However, knowledge of manatee life-history attributes increased and now permits the development of a population model. We describe a

No abstract available.

The magnitude and frequency of the 1993 peak discharges in the upper Mississippi River Basin are characterized by applying Bulletin 17B and L-moment methods to annual peak discharges at 115 unregulated watersheds in the basin. The analysis indicated that the 1993 flood was primarily a 50-year or less event on unregulated watersheds less than about 50,000 km2 (20,000 mi2). Of the 115...

Abstract not supplied at this time

N-terminal amino acid sequences for vitellogenin (Vtg) from six species of teleost fish (striped bass, mummichog, pinfish, brown bullhead, medaka, yellow perch and the sturgeon) are compared with published N-terminal Vtg sequences for the lamprey, clawed frog and domestic chicken. Striped bass and mummichog had 100% identical amino acids between positions 7 and 21, while pinfish, brown...

Abstract not supplied at this time

Selection studies involving multiple intercorrelated independent variables have employed multiple regression analysis as a means to estimate and partition natural and sexual selection's direct and indirect effects. These statistical models assume that independent variables are measured without error. Most would conclude that such is not the case in the field studies for which these...

North America has the richest fauna of temperate freshwater fishes in the world, with about 800 native species in the waters of Canada and the United States. The center of this diversity is in the southeastern United States, where as many as 500 species may exist (62% of the continental fauna north of Mexico). Many coastal marine species also enter fresh waters of the Southeast, and at...

No abstract available.