Geology topics
Publications and source records attributed to C. J. Stafford.
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.
Blood biopsy for chemical analysis is a valuable technique for evaluating chemical exposure of birds in the wild without harming the birds. Field conditions, however, often make sample storage difficult. Better methods than freezing are needed to improve the interpretive value of chemical analysis of the sample. The use of formalin was explored for this purpose. A pooled sample of blood containing naturally incorporated 1,1-bis-(p-chlorophenyl)-2,2,2-trichloroethane (DDT), 2,2-bis-(p-chlorophenyl)1,1 dichloroethylene (DDE), and dieldrin was subdivided into 30 samples, of which 10 were frozen, 10 more were kept at room temperature, and 10 were formalinized by adding I part of chemically pure formalin to 20 parts of blood. The formalinized samples yielded the highest and least variable concentrations of chemicals. The field procedures are outlined.
Mink (Mustela vison) and river otters (Lutra canadensis) collected during the 1978-1979 trapping season in Oregon were analyzed for organochlorine pesticide and polychlorinated biphenyl (PCB) residues. PCB residues were most frequently encountered in both species from the Lower Columbia River. PCB residues in 6 of 9 Columbia River mink livers were as high as those reported in livers of experimental female mink that experienced total reproductive failure after eating a PCB-contaminated diet of 0.64 ppm for 160 days. Also, some fish from the Columbia River contained PCBs (range 0.24-2.8 ppm) equivalent to or higher than the dietary dosage given in the same laboratory study. River otter livers from the same area contained even higher levels of PCBs [(M) geometric mean 9.3 ppm, (F) geometric mean 3.5 ppm], but the relative sensitivity of the 2 species to these contaminants is unknown. The river otter harvest along the Lower Columbia River has declined in the last 3 decades, whereas the statewide harvest trend is upward. PCBs were generally low or not detected in the remainder of the Oregon locations studied. Lower Columbia River collections also showed the highest organochlorine pesticides (mainly DDE) in both species. We are less concerned about the DDE residues reported, particularly in mink, because mink are less sensitive to DDT than to PCBs. Population declines of both mink and otters resulting from PCB contamination may have occurred, and may still be occurring, along the Lower Columbia River.
No abstract available.
Ruptured-yolk peritonitis was responsible for the death of a royal tern. Lodgment of eggs in the oviduct was probably due to reverse peristalsis brought about by breakage of the thin-shelled eggs and secondary bacterial infection. The thin shells were apparently not related to the low levels of DDE and other organochlorine pollutants found in tissues and egg contents.