Tracking Polar Bears
Arctic sea ice, the vital habitat of polar bears, has undergone basin-wide reductions in extent and thickness over the past few decades. Indices used to delineate pan-Arctic polar bear habitat suggest future sea ice declines will result in loss of “critical” habitat. To aid and refine local management decisions season-specific resource selection functions (RSF) were developed from satellite radio-telemetry locations of adult female polar bears and data from several sources including the European Space Agency’s environmental satellite (ENVISAT), the National Oceanic and Atmospheric Adminis
USGS Science Supports Early Humanitarian Response to Famine Conditions in East Africa
USGS scientists, in partnership with USAID, developed forecasts of drought conditions and supported the United Nations famine declaration for southern Somalia. Parts of eastern Africa, including Somalia, experienced two consecutive seasons of poor rainfall, resulting in the worst drought in 60 years. Crops failed, livestock deaths were widespread, and food prices were high. While the depth of the crisis outstripped the capacity of the humanitarian response, USGS support to the Famine Early Warning Systems Network (FEWS NET) helped mitigate severe malnutrition and mortality. Sponsored
Changing Arctic Ecosystems: Mapping Long-term Changes in Vegetation Important to Migratory Birds and Mammals of Alaska’s Arctic Coastal Plain
A primary objective of the Changing Arctic Ecosystems Initiative of the USGS Alaska Science Center is to measure and forecast the effect of changing terrestrial ecosystem processes on wildlife populations along Alaska’s Arctic Coastal Plain. The Initiative seeks to understand the environmental changes resulting from warming during the 20th and 21st century, and how these changes are impacting molting and breeding bird populations, such as those of Pacific Black Brant geese and White-fronted geese. Time series image analysis and field sampling are used to determine th
Compiling and Analyzing Condor Tracking Data
Historically, the endangered California condor ranged from southern Canada to northern Mexico, but by the late 1970s, only about 30 birds remained in a small area in southern California. A captive breeding program was established, and condors that were reintroduced to the wild were tracked by radio and satellite. This information helps managers develop a broad understanding of condor populations, refine management strategies, and evaluate new sites for releases.
Documenting Year-round Movements of Swainson's Hawks
Most swainson’s hawks migrate between North American breeding grounds and South America, but little is known about their migration, use of stopover areas, and movements on the pampas of South America. USGS scientists characterized the annual patterns of long-distance movement and delineated migration routes of 46 hawks tagged in separate nesting areas throughout their breeding range. Satellite telemetry tracking the hawks showed they followed three main routes south, converged along the east coast of central Mexico, and then followed a narrow corridor to an area in central Argentina.
Impacts of Fire on Greater Everglades Ecosystem
Historically, fire has been influential in shaping and maintaining the biotic components of the Greater Everglades ecosystem. As a result, Everglades National Park has been at the forefront of NPS fire policy development. In 1948 it was the first to allow prescribed burns and one of the first to develop a fire management plan.
Mapping landscape features suitable for polar bear maternal dens in coastal regions of the National Petroleum Reserve – Alaska, using an IfSAR digital terrain model
The Arctic Coastal Plain (ACP) in northern Alaska provides denning habitat for polar bears and has several oil and gas fields currently in development or extraction phases (the National Petroleum Reserve, Alaska). To assure that wintertime exploration and development activities do not disrupt denning or threaten survival of cubs, managers need to know the distribution of the landscape features where polar bears are most likely to dig maternal dens. Maps of potential den habitat were developed for the central and eastern portions of the ACP using standard photogrammatic techniques. The
Modeling fire severity and wildfire-driven changes in land cover
Wildfires are the primary disturbance in the Alaskan boreal forest. Burned area and fire severity are increasing in response to increased temperatures in the region. Fires consume aboveground biomass and surface organic materials, which affects post-fire succession. Black spruce stands, which constitute 70 percent of the forest cover in the Alaskan boreal forest, may become dominated by deciduous vegetation if most of the surface organic material is consumed by fire.
Monitoring Manatee Habitat
Florida manatees range along the Gulf of Mexico coast from Florida to Texas, little is known about manatee use areas and habits west of the Suwannee River. Understanding manatee distribution and resource use is necessary for managing northern Gulf of Mexico coastal habitats. Knowledge of shelter and forage resources for manatees and other species, such as fish and sea turtles is important. GPS telemetry records from radio-tagged manatees linked to a camera-based sampling system were used to detect and characterize seagrass beds.