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At least 901 records · Page 50Linked to original sources
USGS1978

Osprey distribution, abundance, and status in western North America: I. The northern California population

An estimated 355 ± 40 pairs (95 percent C.I.) of Ospreys (<i>Pandion haliaetus carolinensis</i>) nested in the northern California survey area in 1975. Eighty-one pairs were estimated along the extreme northern coast in Del Norte and Humboldt Counties. One hundred and forty-four pairs were estimated along California's northern coast in Mendociuo, Sonoma, and Marin Counties. The northern interior region, primarily in Siskiyou, Trinity, Shasta, Lassen, and Plumas Counties, contained an estimated 130 pairs. Forty-nine percent of the interior Osprey population is associated with reservoirs that were not present in 1900. We believe more Ospreys are present in the interior now than 75 years ago because of the increase in suitable habitat; nevertheless, populations at Shasta Lake and Clair Engle Lake are now exhibiting below-normal production rates and local declines. The long-term status of the coastal population, nesting along rivers, streams, and bays, is not clear. Recent production rates from two segments of the coastal population appear to be normal, but production at Usal Creek is below normal.

California↗
USGS2000

Influence of calcium on the distribution of the pheasant in North America

Rapid Bioassessment Protocols (RBP) and the Sediment Quality Triad (SQT) were used to evaluate the biological effects of a municipal waste-water treatment facility (WWTF) on a small southern stream. During major storm events, raw sewage from the WWTF is released directly into the stream. The headwaters of the stream also receive non-point surface runoff from urban areas. RBP analyses, which included benthos, fish and habitat evaluations, and SQT, including the benthos (from the RBP), contaminant analyses (metals, organochlorine pesticides, PCBs and PAHs) andl toxicity tests of depositional sediment (exposures of Hyalella azteca to solid-phase sediment and pore water) were conducted at five sites on the stream (two upstream of the WWTF and three downstream). The stream has been channelized throughout its entire length, resulting in high, unstable banks, degraded stream channel, and unstable substratum. RBP analyses indicated that the two stations upstream of the WWTF were degraded due to poor physical habitat quality (unstable benthic substratum and lack of fish habitat). The SQT also showed reduced habitat quality at the two stations above the WWTF, but the cause was attributed to high concentrations of PAHs and metals in the sediments. The increased discharge and stabilized base flow provided by the WWTF improved habitat quality downnstream, although conditions were still impaired due to the habitat alteration. Though the causes of degradation were attributed to different factors (physical habitat vs. contamination), there was close concordance between the RBP and SQT in identifying the degraded sites in this stream. The combination of these two procedures provides a robust examination of environmental quality utilizing the weight of evidence approach.

Society of Environmental Toxicology and Chemistry,↗