نتایج جستجو برای: waterfowl
تعداد نتایج: 1321 فیلتر نتایج به سال:
The Prairie Pothole Region of the northern Great Plains is an important region for waterfowl production because of the abundance of shallow wetlands. The ecological significance of the region and impacts from intensive agriculture prompted the U.S. Environmental Protection Agency to select it as one of the first areas for developing and evaluating ecological indicators of wetland condition. We ...
Waterfowl frequently acquire high-energy agricultural seeds in harvested and unharvested croplands during migration and winter. Estimates of agricultural seed biomass in harvested and unharvested corn, soybean, and grain sorghum fields do not exist or are outdated for the southeastern United States. Therefore, we estimated seed biomass in 105 harvested and 59 unharvested corn, soybean, and grai...
Abstract Waterfowl managers first recognized the problem of lead poisoning in ducks from ingestion spent shot (pellets) over 100 years ago. The phaseout for waterfowl hunting began Atlantic Flyway 1970s. Lead was subsequently banned throughout United States and Canada prior to 2000. We compared blood levels American black Anas rubripes wintering coastal New Jersey 1978, ban, 2017, about 39 afte...
Relatively little is known about the distribution of avian paramyxoviruses (APMVs) among wild birds in Japan. Surveillance of APMV in migratory waterfowl was conducted in the San-in region of western Japan during winters of 2006 to 2012. A total of 16 avian paramyxoviruses consisting of 3 lentogenic Newcastle disease viruses (NDVs), 12 APMV-4 and 1 APMV-8 were isolated from 1,967 wild-bird feca...
Lead poisoning from the ingestion of spent shotgun pellets has been recognized as an important disease of North American waterfowl since Bellrose's (1959) research >40 years ago. Nation-wide regulations banning the use of lead shot for waterfowl hunting were established in 1991. We compared the prevalence of lead exposure in American black ducks (Anas rubripes) wintering on 2 areas in Tennessee...
From 1994 to 1999 in the Lower Fraser Valley region of southwest Canada, fonofos (Dyfonate G) was recommended for control of introduced wireworm (Agriotes spp.) pests on potato and other root crops. As part of a wildlife-monitoring program, we collected 15 raptors, including 12 bald eagles (Haliaeetus leucocephalus), found dead or debilitated on or near agricultural lands with severely inhibite...
abstract the objective of this paper was to determine species diversity of wintering waterbirds from a ten-year (2002-2011) monitoring in meyghan wetland. data for calculating the estimates of biodiversity come from the midwinter census by using a total count from the department of the markazi province's environment. data analysis for determine species diversity carried out by using ecolog...
The current network of weather surveillance radars within the United States readily detects flying birds and has proven to be a useful remote-sensing tool for ornithological study. Radar reflectivity measures serve as an index to bird density and have been used to quantitatively map landbird distributions during migratory stopover by sampling birds aloft at the onset of nocturnal migratory flig...
The use of unmanned aerial vehicles (UAVs) for ecological research has grown rapidly in recent years, but few studies have assessed the disturbance impacts of these tools on focal subjects, particularly when observing easily disturbed species such as waterfowl. In this study we assessed the level of disturbance that a range of UAV shapes and sizes had on free-living, non-breeding waterfowl surv...
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