Steller sea lion satellite telemetry data used to determine at-sea distribution in the western-central Aleutian Islands, 2000-2013

This dataset was used for an analysis of the at-sea distribution of Steller sea lions in the western-central Aleutian Islands, Alaska. This analysis was prepared to support the 2014 Section 7 Biological Opinion evaluating effects of commercial groundfish fisheries on Steller sea lion populations. In this study we combined all telemetry deployments during 2000-2013 in the central and western Aleutian Islands, including recent deployments on adult females, and conducted a spatial analysis to identify patterns of use relative to sea lion critical habitat and bathymetry in an area of intense fisheries management measures intended to reduce potential competition. The analytical approach modeled travel paths using the continuous-time correlated random walk model (CTCRW; Johnson et al. 2008, Ecology 89:1208-1215.). The CTCRW model output was used to show habitat use by individual to indicate intra-animal variation, then aggregated in a by age-class, season, criticalhabitat zone (<3 nmi, 3-10 nmi, 10-20 nmi, >20 nmi), or occurrence inside/outside of the 200 m isobath contour as possible factors. Some of the deployments included in this analysis have also been used in previous published studies (Call et al., 2007; Fadely et al., 2005; Lander et al., 2011a; Lander et al. 2011b; Lander et al., 2010; Lander et al., 2009; Loughlin et al., 2003; Pitcher et al., 2005; Rehberg and Burns, 2008).