Acoustic scattering layers are ubiquitous, horizontally extensive aggregations of both vertebrate and invertebrate organisms that play key roles in oceanic ecosystems. However, currently there are no conventions or widely adaptable automatic methods for identifying these often dynamic, spatially complex features, so it is difficult to consistently and efficiently describe and...
Acoustic echo sounders designed to map and discriminate organisms in the water column have primarily been deployed on ships. Because of acoustic attenuation of higher frequencies used to detect and discriminate micronekton and nekton, this has effectively restricted the range of this information to the upper water column. In an...
We used split-beam acoustic techniques to observe free-swimming of jumbo squid Dosidicus gigas during 4 cruises in the Gulf of California. Four-dimensional spatio-temporal data revealed that at night in shallow water, jumbo squid were using ascending, spiral-like swimming paths to emerge from extremely dense aggregations, and were likely foraging on...
Many wind-power facilities in the United States have established effective monitoring programs to determine turbine-caused fatality rates of birds and bats, but estimating the number of fatalities of rare species poses special difficulties. The loss of even small numbers of individuals may adversely affect fragile populations, but typically, few (if...
Intrinsic and extrinsic factors affect vital rates and population-level processes, and understanding these factors is paramount to devising successful management plans for wildlife species. For example, birds time migration in response, in part, to local and broadscale climate fluctuations to initiate breeding upon arrival to nesting territories, and prolonged inclement...
Intrinsic and extrinsic factors affect vital rates and population-level processes, and understanding these factors is paramount to devising successful management plans for wildlife species. For example, birds time migration in response, in part, to local and broadscale climate fluctuations to initiate breeding upon arrival to nesting territories, and prolonged inclement...
Background: Improved maps of species distributions are important for effective management of wildlife under increasing anthropogenic pressures. Recent advances in lidar and radar remote sensing have shown considerable potential for mapping forest structure and habitat characteristics across landscapes. However, their relative efficacies and integrated use in habitat mapping remain largely...
Seabirds have often been proposed as environmental indicators. Beached bird data may provide an additional data source and such data is efficacious because it can reliably be collected by volunteers. In addition to anthropogenic factors, such as oil spills, changes in the ocean-atmosphere can affect carcass beaching rate in 3...
Rice, maize, sorghum, wheat, barley and the other
major crop grasses from the family Poaceae
(Gramineae) are mankind’s most important source
of calories and contribute tens of billions of dollars
annually to the world economy (FAO 1999, http://www.fao.org; USDA 1997, http://www.usda.gov).
Continued improvement of Poaceae crops is necessary
in order...
LiDAR (Light Detection And Ranging) is an emerging remote-sensing tool that can provide fine-scale data describing vertical complexity of vegetation relevant to species that are responsive to forest structure. We used LiDAR data to estimate occupancy probability for the federally threatened marbled murrelet (Brachyramphus marmoratus) in the Oregon Coast Range...