Publications

Multichannel seismic reflection profiles from the Southeast Georgia Embayment and northern Blake Plateau show reflectors that have been correlated tentatively with horizons of known age. The top of the Cretaceous extends smoothly seaward beneath the continental shelf and Blake Plateau, unaffected at the present shelf edge. A reflector inferred to correspond approximately to the top of the Jurassic

No abstract available.

Partly serpentinized peridotite of early Keweenawan age crops out in two places along a 20-kilometer-long zone of positive aeromagnetic anomalies in northern Marquette County, Michigan. Most of the area is mantled by Pleistocene drift with few bedrock exposures.Petrographic and electron microprobe studies show that the peridotite was originally a plagioclase lherzolite containing 40 to 50 percent 

The Indiana State Board of Health is developing a water-quality management plan that includes establishing limits for wastewater effluents discharged into Indiana streams. A digital model calibrated to conditions in West Fork Blue River was used to predict alternatives for future waste loadings that would be compatible with Indiana stream water-quality standards defined for two critical hydrologic

Three generations of mallard ducks (Anas platyrhynchos) were fed either a control diet or a diet containing 0.5 ppm mercury in the form of methylmercury. The levels of mercury in adult tissues and eggs remained about the same over 3 generations. The methylmercury diet had no effect on adult weights or weight changes during the reproductive season. Females fed a diet containing 0.5 ppm mercury laid

Many raptorial species in the Pacific Northwest have not been studied from the viewpoint of pollutant contamination. The Swainson's Hawk (Buteo swainsoni) is particularly interesting because of its highly migratory characteristic; it apparently winters primarily in Argentina (Brown and Amadon 1968, Houston 1968). White and Cade (1977) and others have suggested Central America and South America as

An estimated 810 ± 55 pairs (minimum estimate) of ospreys (Pandion haliaetus) were nesting in the study area during our survey (24 March-1 April 1977). Approximately 174 pairs nested along the Pacific side of Baja California, 255 pairs along the gulf side, 187 pairs on the Midriff Islands, and 194 pairs in coastal Sonora and Sinaloa. Most nested on cliffs adjacent to the sea (59%); some nested on

Least Tern nesting colonies on the Cape Romain National Wildlife Refuge and surrounding areas in South Carolina were studied from 1971 through 1975. We located 10 colonies including 6 on the Refuge and 4 on nearby coastal islands. The number of nests in each colony ranged from several up to 220. Least Terns began reproductive activity in April, and the egg-laying period ranged from May to July. Th

Concentrations of mercury in passerine birds fed diets containing 40 ppm methylmercury were similar in tissues of birds that died from mercury poisoning and in those that were sacrificed after half the group had died. Residues were higher in tissues of birds that died, but the differences were not statistically significant. Residue levels were highest in livers, followed by kidneys and brains. Le

Acute oral (po) and 24-hr percutaneous (perc) LD50 values for 21 common pesticides (19 anticholinesterases, of which 18 were organophosphates, and one was a carbamate; one was an organochlorine central nervous system stimulant; and one was an organonitrogen pneumotoxicant) were determined in mallards (Anas platyrhynchos). Three of the pesticides tested were more toxic percutaneously than orally. A

No abstract available.

Experiments involving dietary toxicity and residue relationships of DDT, dieldrin, and endrin were conducted with short-tailed shrews. Dietary concentrations of DDT dissolved in vegetable oils were usually more toxic than diets containing comparable amounts of powdered DDT. Younger shrews, particularly females, were more tolerant of powdered DDT than older animals; yet, there were no conspicuous a