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Captive, crippled bald eagles unsuitable for release were fed lead shot to determine diagnostic criteria for lead poisoning. The eagles were fluoroscoped and bled periodically to determine shot retention and blood delta--aminolevulinic acid dehydratase activity. Microscopic examination revealed renal tubular degeneration, arterial fibrinoid necrosis and myocardial necrosis. Acid-fast intra-nuclear inclusion...

A systematic survey was conducted in the Tidal Potomac River in 1978 to determine the presence, abundance, and phenology of submersed aquatic macrophytes. The survey covered 81.5 km of main river and 59.3 km of tributary on the Maryland shore. Four regions were selected for the study: (1)...

In 1976 and 1977, die-offs of birds of several species occurred in Umatilla and Morrow counties, Oregon. Detection of high levels of heptachlor epoxide (HE) in tissues of Canada geese (Branta canadensis) prompted this study to determine the extent and impact of heptachlor contamination on geese on two study areas...

Lethal residues of heptachlor epoxide in brains of birds fed heptachlor ranged from 9 to 27 ppm wet weight; residues of oxychlordane in birds fed oxychlordane ranged from 6 to 16 ppm; both were diagnostically distinct from those in equally exposed survivors. In birds fed chlordane, brains of those that...

For the first time (1978) artificial insemination (AI) with frozen greater sandhill crane (Grus canadensis tabida) semen resulted in fertile eggs and chicks. During the 2 year (1977-78) study, 6 of 27 eggs produced were fertile. Three chicks hatched. Semen samples used for insemination were frozen and stored in liquid...

Endrin residues in brains that are diagnostic of death were determined for several species of birds. Residues of 0.8 ppm or more of endrin in brain meant death; 0.6 ppm or less meant survival; between was a zone of overlap. These criteria indicate that some wild birds of the...

Data from published bird censuses were used to determine changes in avian communities in relation to plant succession, fire, type conversion, and timber management practices in lowland conifer forests in the northeastern United States. With modifications in current logging practices, habitat for the bird species that nest in undisturbed...

Many of the insectivorous songbird species that winter in the tropics are dependent on large unbroken tracts of forest during the breeding season. These species are disappearing from localities where forests are becoming fragmented. By long-range planning, managers can prevent local extinctions of these area-sensitive birds through use...

Evaluation of the effects of environmental contaminants on wildlife is geared to interpreting events in the field, especially population effects, and both field and laboratory studies are planned for this purpose; procedures are adapted to specific problems and therefore do not include strict protocols or routine testing. Field evaluations include...

British workers showed that in rats the endrin metabolite, 12-ketoendrin, was five times as toxic as endrin, was probably the ultimate cause of death, and was the main form of endrin in the brain at death. In cows and rabbits, however, they detected little of this metabolite. They...

Geese described are non-migratory, free-flying Todd's Canada geese (Branta canadensis interior). The genealogy of 261 of these geese was traced by archival research and three years of field observations. Nest locations and densities, preferences for various types of artificial nest structures, clutch sizes, hatching success, brood survival to...

This collection of photographs reflects 100 years of public service by the U.S. Geological Survey since its founding on March 3, 1879: "... for the classification of the public lands, and examination of the geological structure, mineral resources, and products of the national domain."...

Lacustrine limestone samples from sedimentary pan deposits at Rooidam, near Kimberley, South Africa, that contain late Acheulian (Fauresmith) artifacts have been dated by 230Th234U and 231Pa235U methods. Results indicate a minimum age of about 200,000 yr B.P. for the terminal Acheulian in the interior of South Africa. ...

Dating samples of corals and shell from the elevated coral reef terrace on Rottnest Island, Western Australia, indicate that in this region away from active plate boundaries the sea stood at least 3 m above present sea level 132,000 ± 5,000 years ago. There is no geologic evidence of other...

A radiographic scanning technique (RST) can produce single continuous radiographs of cores or core sections up to 1.5 m long and up to 30 cm wide. Changing a portable industrial X-ray unit from the normal still-shot mode to a scanning mode requires simple, inexpensive, easily constructed, and highly durable equipment....

Surficial sediments of the Kodiak shelf, Gulf of Alaska, contain various amounts of volcanic ash whose physical properties indicate that it originated from the 1912 Katmai eruption. The distribution of ash is related to the shelf physiography and represents redistribution by oceanic circulation rather than the original depositional pattern from...

Analyses of 24 high-resolution seismic-reflection profiles that were collected during local and regional surveys show that small-scale slump deposite are ubiquitous whthin the intercanyon areas of the Continental Slope of the Middle Atlantic Bight. The deposits involve the upper 10-90 m of sediments, extend downslops for 1.8-7.2 km, and are...

The mechanical interaction between a fluid-filled fracture (e.g., hydraulic fracture joint, or igneous dike) and the earth's surface is analyzed using a two-dimensional elastic solution for a slit of arbitrary inclination buried beneath a horizontal free surface and subjected to an arbitrary pressure distribution. The solution is obtained by...

Microbial contaminants may be introduced on outcrop as well as en route to or in the laboratory. Micropseudofossils may be natural or man-made. It is possible to recognize such misleading objects and important that they are not allowed to dilute the growing record of authentic pre-Phanerozoic life. Filamentous microbial contaminants...

Rocks deposited near sea level under marine, estuarine, and lacustrine conditions, and located along the course of the lower Colorado River from the mouth of the Grand Canyon as far as the Mexican border, have been displaced to present positions as high as 880 m a.s.l. and as low as...

The NW—SE trending southern California coastline between the Palos Verdes Peninsula and San Diego roughly parallels the southern part and off-shore extension of the dominantly right-lateral, strike-slip, Newport—Inglewood fault zone. Emergent marine terraces between Newport Bay and San Diego record general uplift and gentle warping on the northeast side of...