Publications

No abstract available.

We present a method of comparing data on habitat use and availability that allows availability to differ among observations. This method is applicable when habitats change over time and when animals are unable to move throughout a predetermined study area between observations. We used maximum—likelihood techniques to derive an index that estimates the probability that each habitat type...

After the Exxon Valdez oil spill of 24 March 1989, 36,115 dead seabirds were recovered from beaches and processed at morgues. Most or all of 1,888 live oiled seabirds brought to rehabilitation centers also died and about 3,260 oiled carcasses were never delivered to morgues. Of these 41,263 carcasses accounted for, we estimated conservatively that only 30,000 were killed by oil pollution...

Sea otter (Enhydra lutris) populations are increasing and expanding into areas of Southeast Alaska where Dungeness crabs (Cancer magister) are commercially harvested. Although sea otters are known to feed on Dungeness crabs, their effects upon crab demography have not been quantified. We censused Dungeness crabs in adjacent areas within Glacier Bay National Park and Preserve with and...

Seaducks (Tribe Mergini) are a diverse group of birds. In North America, many species nest in boreal or arctic habitats in Canada and Alaska and winter in ice-free coastal, marine, and freshwater habitats. Data from long- term surveys, population studies, and local knowledge suggest that some populations and species of seaducks have declined over the past decades. In most cases, the...

One-hundred-and-ninety-one samples of blood serum collected from 186 polar bears (Ursus maritimus) between 1987 and 1992 were analysed for morbillivirus antibodies. The samples were collected in the Bering, Chukchi and East Siberian seas. Sixty-eight samples (35.6 per cent) had morbillivirus antibody titres > 5; the percentage of positive samples ranged from 26.2 to 46.2 per cent from...

No abstract available.

The activity and feeding behavior of ovigerous Dungeness crabs, Cancer magister, were examined as part of a long-term study. Part of this study surveyed Bartlett Cove in Glacier Bay, Alaska, during the spring of 1994 where 50 commercial pots were soaked for 24 hours. Catch per unit effort (CPUE), dispersion, and stomach samples of male, nonovigerous female, and ovigerous female crabs...

Patterns of micro- to mesoscale distribution of Dungeness crabs (Cancer magister) in nearshore habitats at five locations in and near Glacier Bay National Park were revealed using subtidal transects. Sampling was conducted in April and September 1992 and 1993 and April 1994. Divers censused crabs by sex and reproductive status (ovigerous/nonovigerous females) along belt transects (2 m x...

Data collected under a double-count protocol during line transect surveys were analyzed using new maximum likelihood methods combined with Akaike's information criterion to provide estimates of the abundance of polar bear (Ursus maritimus Phipps) in a pilot study off the coast of Alaska. Visibility biases were corrected by modeling the detection probabilities using logistic regression...

Several years ago, Science published an important essay (Ludwig et al. 1993) on the need to confront the scientific uncertainty associated with managing natural resources. The essay did not discuss instream flow standards explicitly, but its arguments apply. At an April 1995 workshop in Davis, California, all 12 participants agreed that currently no scientifically defensible method...

Bayesian methods have been proposed to estimate optimal escapement goals, using both knowledge about physical determinants of salmon productivity and stock-recruitment data. The Bayesian approach has several advantages over many traditional methods for estimating stock productivity: it allows integration of information from diverse sources and provides a framework for decision