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Abstract Wind has become one of the fastest growing sources of renewable energy worldwide, but widespread and often extensive fatalities of bats have increased concern regarding the impacts of wind energy development on bats and other wildlife. We synthesized available information on patterns of bat fatalities from a review of 21 postconstruction fatality studies conducted at 19 facilities in 5 United States regions and one Canadian province. Dominance of migratory, foliage- and tree-roosting lasiurine species (e.g., hoary bat [Lasiurus cinereus]) killed by turbines was consistent among studies. Bat fatalities, although highly variable and periodic, consistently peaked in late summer and fall, coinciding with migration of lasiurines and other species. A notable exception was documented fatalities of pregnant female Brazilian freetailed bats (Tadarida brasiliensis) in May and June at a facility in Oklahoma, USA, and female silver-haired bats (Lasionycteris noctivagans) during spring in Tennessee, USA, and Alberta, Canada. Most studies reported that fatalities were distributed randomly across turbines at a site, although the highest number of fatalities was often found near the end of turbine strings. Two studies conducted simultaneously in the same region documented similar timing of fatalities between sites, which suggests broader patterns of collisions dictated by weather, prey abundance, or other factors. None of the studies found differences in bat fatalities between turbines equipped with lighting required by the Federal Aviation Administration and turbines that were unlit. All studies that addressed relationships between bat fatalities and weather patterns found that most bats were killed on nights with low wind speed (<6 m/sec) and that fatalities increased immediately before and after passage of storm fronts. Weather patterns may be predictors of bat activity and fatality; thus, mitigation efforts that focus on these high-risk periods could reduce bat fatality substantially. We caution that estimates of bat fatality are conditioned by length of study and search interval and that they are biased in relation to how searcher efficiency, scavenger removal, and habitat differences were or were not accounted for. Our review will assist managers, biologists, and decision-makers with understanding unifying and unique patterns of bat fatality, biases, and limitations of existing efforts, and it will aid in designing future research needed to develop mitigation strategies for minimizing or eliminating bat fatality at wind facilities.  相似文献   
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Hydrococcus brazieri and Arthritica semen on a sandflat at Coodanup,Peel Inlet, Western Australia, accounted for 89.5% of totalmollusc numbers. The mean density of H. brazieri was 9487 m–2and A. semen averaged 8105 m–2. H. brazieri grew at 0.5mm month–1 and reached maturity in 4 months; A. semengrew at 0.3 mm month–1 and reached maturity in 6 months.Somatic production in the Peel-Harvey estuarine system was estimatedto be 0.5 g m–2yr–1for H. brazieri and 4.1 g m–2yr–1for A. semen. The positions of these two species in the estuarinefoodweb is discussed. (Received 26 June 1981;  相似文献   
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At Makthlawaiya, in the Paraguayan Chaco, the prevalence of Trypanosoma (Schizotrypanum) cruzi infection among both domestic Triatoma infestans and domestic dogs was 38%, and IgG anti-T. cruzi antibody was detected by the quantitative enzyme-linked immunosorbent assay (ELISA) in 80% (105/133) of human sera. Ninety percent (25/28) of T. cruzi strains isolated from both T. infestans and dogs showed heterozygous isoenzyme profiles for glucose phosphate isomerase, phosphoglucomutase and 6-phosphogluconate dehydrogenase. These strains appeared to be closely related to Bolivian zymodeme 2. Three Paraguayan T. cruzi strains showed homozygous isoenzyme profiles, similar to those of major Brazilian zymodemes. It was concluded that T. cruzi strains with heterozygous isoenzyme profiles predominate in domestic transmission cycles in this highly endemic area of the Paraguayan Chaco.  相似文献   
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The Ordovician was a time of extensive and pervasive low-magnesium calcite (LMC) precipitation on shallow marine sea floors. The evidence comes from field study (extensive hardgrounds and other early cementation fabrics in shallow-water carbonate sequences) and petrography (large volumes of marine calcite cement in grainstones). Contemporaneous sea-floor events, particularly relationships with boring and encrusting organisms and reworking in sequences of intraformational conglomerates, confirm the early timing of such LMC cementation, and also of widespread associated aragonite dissolution. Local evidence points to the dissolved aragonite as a significant source of the calcite cement. This scenario, and the fabrics that provide the evidence for it, are likely to be pointers to other times in the stratigraphic record when LMC was the predominant shallow marine precipitate (Calcite Sea times). The combination of rapid calcite precipitation and aragonite dissolution at a time early in the Phanerozoic when many major invertebrate groups were becoming established may have acted as an influence on the evolution of both their skeletal mineralogy and their ecology.  相似文献   
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To aid in understanding the structure, dispersal and genetic dynamics of their populations, we developed microsatellite and amplified fragment length polymorphism (AFLP) markers for the sea palm, Postelsia palmaeformis (Laminariales) for samples taken from nine sites in the area of Cape Flattery, Washington State, USA. We identified two AFLP primers that yielded 798 variable fragments and five microsatellite markers with three to seven alleles each. We also report patterns of allelic variation for four previously identified microsatellite markers in this species and several new alleles.  相似文献   
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