Heavy use of outdoor recreation areas in the United States
since World War II is endangering their quality. Demand made by a
rapidly growing population with rising personal incomes and increasing
leisure time is expected to grow 50 percent nationally and 146 percent in Oregon by 1975. In Oregon, population,...
I developed a priori hypotheses and used logistic regression to model Greater Sandhill
Crane (Grus canadensis tabida) nest success in relation to weather, habitat and management variables for cranes breeding at Malheur National Wildlife Refuge (MNWR) in southeast Oregon. My primary interest was to investigate the effects of habitat conditions...
Lepidium latifolium L. (perennial pepperweed, LEPLA) is an exotic invader throughout western North America. At Malheur National Wildlife Refuge (MNWR) in southeast Oregon, it has invaded about 10% of meadow habitats that are important for wildlife. This study's objective was to determine the most effective and least environmentally harmful treatment...
Bullfrogs were introduced into Oregon in the early 1900s and have become widespread members of many wetland communities. Little is known of their ecology outside their native range, although they may play a role in the current declines observed in native herpetofauna. I analyzed the diets of 401 bullfrogs from...
I conducted 14-22 waterbird and raptor censuses each year from 1992-1995 during late April or early May through October. I observed 44 waterbird and 13 raptor species, including hatch year individuals of seven waterbird species. The records for each census are given.
From 25 April through 30 October 1992, I conducted 14 waterbird and raptor censuses at Cabell Marsh. I observed 33 waterbird taxa and seven raptor species, including hatch-year individuals of five waterbird species. The records for each census are given.
Dedicated to the preservation and promotion of many of the nation’s most threatened and endangered species, the W.L. Finley National Wildlife Refuge is highly invested in the management of some of the last remaining upland prairies once prevalent throughout Oregon's Willamette Valley. More than a century of land fragmentation, fire...
The Pantanal is one of the largest wetlands in the world, covering 195,000 km2 across Brazil, Bolivia and Paraguay. It has a unique annual flooding regime with the majority of land being completely inundated during the wet season, which provides important habitat for threatened species such as jaguars (Panthera onca)...
Report by Portland State University's Oregon Biodiversity Information Center (ORBIC), part of the Oregon University System's Institute for Natural Resources.
Greater Sage-Grouse (Centrocercus urophasianus) have experienced declines throughout their range over the last 50 years. Long-term declines in sage-grouse abundance in Nevada and Oregon have been attributed to reduced productivity. From 1995-1997, sage-grouse production on Sheldon National Wildlife Refuge (SNWR), Nevada was greater compared to Hart Mountain National Antelope Refuge...