Charles J. Henny (Former Employee)

In general. decreases in OC contamination in North America are unmistakable. This is documented by the NPMP. but. more importantly. it is borne out by improvements in the reproduction and population status of the brown pelican. bald eagle, peregrine falcon, and osprey. However, some OC contamination still persists, and several species, particularly predatory birds and insectivorous bats...

Nesting Ospreys (Pandion haliaetus) in the contiguous United States now number about 8,000 pairs. Five regional populations exist (in order of abundance): Atlantic Coast, Florida and Gulf Coast, Pacific Northwest, Western Interior, and Great Lakes. Pesticides severely impacted the populations in the northern portion of the Atlantic Coast (Boston to Cape May) and the Great Lakes, but both...

Habitat data were evaluated at 34 Goshawk (Accipiter gentilis), 31 Cooper's Hawk (A. cooperii), and 15 Sharp-shinned Hawk (A. striatus) nest sites in coniferous forests of northeastern Oregon. Crown volume profiles indicate a strong similarity in vegetative structure at nest sites of cooperii and striatus; both commonly nest in younger successional stands than gentilis. Habitat...

No abstract available.

Three subspecies of Peregrine Falcons (Falco peregrinus) breed in North America: F. p. anatum, formerly bred in all eco-geographic regions of North America south of the Arctic tundra, except for the immediate vicinity of the northwest Pacific Coast; F. p. tundrius breeds in the Arctic tundra; and F. p. pealei, a relatively sedentary form, occupies the region of the northwest Pacific...

A single egg was collected at 62 nests of 10 seabird species from Oregon in 1979. The eggs were analyzed for organochlorine contaminants; contemporary shell thickness was compared with eggshells collected during earlier time periods. Concentrations of DDE and PCB's in 1979 were generally low with the most contaminated species being the Double-crested Cormorant (Phalacrocorax auritus)...

Blood samples from 433 Peregrine Falcons (Falco peregrinus) during fall and spring migrations, 1976-80, indicated that most of their pesticide burden, primarily DDE, was accumulated on wintering grounds in Latin America. DDE in spring migrants returning from Latin America for the first time declined significantly from 1979 to 1980. Only about 10% of breeding-age females contained...

Background levels of DDT and its metabolites (ZDDT) were extremely low or not detected in five species of forest-dwelling bats in northeastern Oregon, i.e., areas not sprayed with DDT in 1974. Other organochlorine pesticides were rarely found and no polychlotinated biphenyls (PCBs) were detected at any time during the study. Four of five species of bats showed significant changes in Z...

Large numbers ofCliff Swallows (Petrochelidon pyrrhonota) died in late May near Burns, Oregon, during cold, wet weather. The brains of five dead birds did not contain lethal concentrations of DDE, and no PCBs were detected.

No abstract available.

Unprecedented declines of the Peregrine Falcon (Falco peregrinus) throughout much of the Northern Hemisphere became apparent during the Madison Peregrine Falcon Conference in 1965 (Hickey 1969). Data from Britain were the most detailed; broken or missing eggs were much more common in 1949-56 than they had been in earlier years (Ratcliffe 1958). Subsequently, Ratcliffe (1967) showed a...

The wintering range of the Great Blue Heron (Ardea herodias) extends further north than does that of any other member of the Ciconiiformes in North America. The northern limits of its range extend along the Pacific coast into southeastern Alaska, into Massachusetts on the Atlantic coast, and inland into southern Montana (Palmer 1962). In the northern part of its range, severe winter...