Abstract. Fifteen reproductive groups of red foxes were observed on Round Island, Alaska during five field seasons. Polygyny occurred among these foxes, correlated with abundant food resources. The predictions of the polygyny threshold model were supported, i.e. polygynous females had equal or better reproductive success than monogamous females.

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We characterized small-scale movement patterns and habitat of acoustic-tagged adult (68 to 220 cm total length) female Pacific halibut during summer and fall in Glacier Bay National Park, Alaska, a marine protected area (MPA). We used net squared displacement analysis methods to identify 2 movement states, characterize individual dispersal patterns, and relate habitat variables to movement scales. Movement states identified for 32 of 43 halibut consisted of (1) a non-dispersive 'residential' movement state (n = 27 fish), where movement was restricted to an average movement radius of 401.3 m (95% CI 312.2−515.9 m) over a median observation period of 58 d, and (2) a 'dispersive' movement state (n = 15 fish), where movements of up to 18 km occurred over a median observation period of 27 d. Some fish (n = 10) exhibited both movement states. Individual fish demonstrated primarily non-random dispersal patterns including home range (n = 17), site fidelity (return to previously occupied locations following forays, n = 6), and shifted home ranges (n = 5). However, we also observed a random dispersal pattern (n = 4) with an estimated mean ± SE diffusion rate of 0.9 ± 0.05 km 2 d −1. Home range size increased with depth but not fish size. Home range locations were associated with heterogeneous habitat, intermediate tidal velocities, and depths <100 m. Observations of non-dispersive movement patterns, relatively small home ranges, and site fidelity for adult females suggest that MPAs such as Glacier Bay may have utility for conservation of Pacific halibut broodstock.

Nielsen, J. K., Taggart, S. J., Shirley, T. C., and Mondragon, J. 2007. Spatial distribution of juvenile and adult female Tanner crabs (Chionoecetes bairdi) in a glacial fjord ecosystem: implications for recruitment processes. – ICES Journal of Marine Science, 64: 1772–1784. A systematic pot survey in Glacier Bay, Alaska, was conducted to characterize the spatial distribution of juvenile and adult female Tanner crabs, and their association with depth and temperature. The information was used to infer important recruitment processes for Tanner crabs in glaciated ecosystems. High-catch areas for juvenile and adult female Tanner crabs were identified using local autocorrelation statistics. Spatial segregation by size class corresponded to features in the glacial landscape: high-catch areas for juveniles were located at the distal ends of two narrow glacial fjords, and high-catch areas for adults were located in the open waters of the central Bay. Juvenile female Tanner crabs were found at nearly all sampled depths (15–439 m) and temperatures (4–8°C), but the biggest catches were at depths <150 m where adults were scarce. Because adults may prey on or compete with juveniles, the distribution of juveniles could be influenced by the distribution of adults. Areas where adults or predators are scarce, such as glacially influenced fjords, could serve as refuges for juvenile Tanner crabs.