Publications

Fifty gallons per minute (3 liters per second) or more may be obtained from wells in almost all parts of the county, but not at all locations. Adequate exploration to find fracture or solution openings is required. Five hundred gallons per minute (30 liters per second) or more may be obtained from some of the carbonate rocks. Linear features are visible on 1:1,000,000-to 1:24,000-scale aerial imag

Blue Marsh Lake is planned as a multipurpose impoundment to be constructed on Tulpehocken Creek near Bernville, Berks County, Pennsylvania. Prior to construction, samples of water, bed material, and soil were collected throughout the impoundment site to determine concentrations of nutrients, insecticides, trace metals, suspended sediment, and bacteria. Analyses of water suggest the Tulpehocken Cr

No abstract available.

This, the fourth in a series of reports on the mallard, (Anas platyrhynchos), deals at length with the harvest of mallards by waterfowl hunters. Long-term summaries of duck hunting regulations (1948- 1974), Migratory Bird Hunting Stamp sales (1934-1974), Hunter Questionnaire (1952-1974), Duck Wing Collection (1960-1974), and Hunter Performance (1965-1972) Survey data for the United States are pres

Before 1920, native populations of brown pelicans (Pelecanus occidentalis carolinensis) were estimated at 50,000 to 85,000 birds in Louisiana and 5,000 in Texas. By 1958, brown pelicans had vanished from two wintering areas in each state, and wintering and breeding birds disappeared from additional areas between 1959 and 1961. By 1963, the disappearance of the brown pelican from Louisiana was comp

Starlings (Sturnus vulgaris) collected in 1973 at 51 sites throughout the continental United States were analyzed for mercury, lead, cadmium, arsenic, and selenium. All samples contained detectable levels of these elements. In general, residues were low: mercury residues ranged from <0.01 to 0.20 ppm: lead, from <0.10 10 3.20 ppm: cadmium, from <0.05 to 0.20 ppm: arsenic, from <0.05 to 1.40 ppm: a

No abstract available.

No abstract available.

Recently obtained high-resolution seismic profiles (400-4,000-Hz band) show evidence of faults in shallow sedimentary strata near the edge of the Atlantic continental shelf off New Jersey. Apparent normal faults having a throw of about 1.5 m displace sediments to within 7 m of the sea floor. The faults appear to be overlain by undeformed horizontal beds of relatively recent age. Several faults 1 t

A study was conducted to determine the levels of DDT and DDE in the livers of 10 species of waterfowl collected in Louisiana from 1970 to 1971. Livers of 48 of 50 specimens contained detectable levels of DDT and/or DDE. DDT residues ranged from 0.01 to 10.90 ppm; DDE levels ranged from 0.02 to 38.69 ppm.

In December 1973, eight ruddy ducks killed in an oil spill on the Delaware River were collected to be analyzed for residues of environmental pollutants. Whole carcasses were analyzed for organochlorine pesticides and livers were examined for lead, cadmium, and mercury. Residues of polychlorinated biphenyls and DDT and/or its metabolites were present in all carcasses. Dieldrin and hexachlorobenzene

Eggs of wild Screech Owls were collected from nests in northwestern Ohio in 1973. One egg was taken from each of 19 nests near the start of incubation. Mean shell thickness in these 19 eggs and mean thickness of 16 unhatched eggs did not differ from 49 archival eggs collected in Ohio and Pennsylvania prior to the widespread use of organochlorine pesticides. Residues were generally low although all