Publications

Over the past decade, the Marbled Murrelet has become a focus of much controversy. It was listed as threatened in Washington, Oregon, and California by the U.S. Fish and Wildlife Service in February 1993. In order to aid the various agencies with management, the Marbled Murrelet Conservation Assessment was formed to bring together scientists, managers, and others to gather all the...

Black bear damage to 108 lodgepole pine trees was found in mixed conifer habitat in central Oregon. No trees of three other conifer species were injured. Eighty-nine percent of the damage occurred in the same year. Nearly 20% of the freshly damaged trees had bark removed from more than 75% of the circumference and, judging from the fate of trees damaged in prior years, probably

We mounted a video camcorder in a single-engine aircraft to estimate nesting density along 10-m wide strip transects in black brant colonies on the Yukon Delta National Wildlife Refuge, Alaska during 1990-1992. A global positioning system (GPS) receiver was connected to the video recorder and a laptop computer to locate transects and annotate video tape with time and latitude

We began a three year study in 1987 to test the feasibility of using sonar in the Togiak River to estimate salmon escapements. Current methods rely on periodic aerial surveys and a counting tower at river kilometer 97. Escapement estimates are not available until 10 to 14 days after the salmon enter the river. Water depth and turbidity preclude relocating the tower to the lower river and...

Black-legged Kittiwakes (Rissa tridactyla) have recently experienced widespread population declines and frequent colony failures throughout the North Pacific. At Glacier Bay National Park, the Margerie Glacier colony was censused visually in 1991 through 1993. In 1993 a new photographic census technique was also tested to assess its feasibility, accuracy, and ease of use, Three years of...

Morphological, behavioral, and life-history differences between Pacific salmon (Oncorhynchus spp.) populations are commonly thought to reflect local adaptation, and it is likewise common to assume that salmon populations separated by small distances are locally adapted. Two alternatives to local adaptation exist: random genetic differentiation owing to genetic drift and founder events...

Survival of young is an important and poorly understood component of waterfowl productivity. We estimated survival of black brant (Branta bernicla nigricans) goslings during summers 1987-89 on the Yukon-Kuskokwim Delta, Alaska, to determine timing and magnitude of gosling mortality and to compare methods of estimating gosling survival. Eighty-two percent of radio-tagged adult females (n...

Emperor Geese (Chen canagica) breed primarily on the Yukon-Kuskokwim Delta, Alaska (Eisenhauer and Kirkpatrick 1977), but a small, poorly quantified proportion of the world's population is known to breed in the Russia Far East (Kistchinski 1976, 1988, Portenko 1981). Eisenhauer and Kirkpatrick (1977) stated that 80 to 90% of all Emperor Geese breed on the Yukon-Kuskokwim Delta, Alaska...

Alloparental care in birds generally involves nonbreeding adults that help at nests or breeding adults that help raise young in communal nests. A less often reported form involves the amalgamation of broods, where one or more adults care for young that are not their own. We observed this phenomenon among Bristle-thighed Curlew Numenius tahitiensis broods in western Alaska during 1990...

Information on the size, distribution, and productivity of the California sea otter population is broadly relevant to two federally mandated goals: removing the population’s listing as threatened under the Endangered Species Act (ESA) and obtaining an “optimal sustainable population” under the Marine Mammal Protection Act. Except for the population in central California, sea otters...

Coho salmon from 10 Washington populations were incubated under controlled conditions to determine the levels of variation in time to hatch among populations and families within populations. The average incubation rate was somewhat slower than that estimated from a quantitative model derived from British Columbia populations, and was slightly faster than that predicted by a Washington...

We studied relationships between body size of female Black Brant goslings (Branta bernicla nigricans) late in their growth period and first year survival, eventual adult body size, breeding propensity, and size and volume of clutches they eventually produced to examine the relationship between growth and fitness in this population. We indexed body size by calculating PC1 scores based on...