In Clayquot Sound, British Columbia, gray whales (Eschrichtius robustus) forage primarily on mysids (Family Mysideae) and also on crab larvae (Family Porcellanidae) that are constrained to specific habitat, which relate to bathymetric depths. In this paper we characterize the interactions of gray whales and their prey by analyzing fine scale spatial-temporal patterns in foraging gray whale distribution within a season. Kernel density estimators are applied to two seasons (1998 and 2002) of highresolution data on foraging by gray whales. By partitioning data from each foraging season into several time periods (12 in 1998 and 11 in 2002), using a temporal autocorrelation function, and generating kernel density estimated surfaces for each time period, it is possible to identify discrete areas of increasing and declining foraging effort. Our results indicate that gray whales forage on mysids throughout a season and opportunistically forage on crab larvae. The episodic crab larvae feeding may reduce, but not eliminate, pressure to mysid populations enabling mysids to reassemble swarms and continue to support gray whale foraging in the latter part of the season. Results suggest that when managing marine environments, gray whale populations require multiple and connected habitats for summer foraging. 356 NELSON ET AL.: GRAY WHALE FORAGING PATTERNS 357
The management of many ocean wildlife species is left in an institutional void, yet certain species command considerable public attention and have burgeoning management problems. In this paper the non-consumptive recreational use of Killer Whales (Orcinus orca) on Canada's Pacific Ocean coast is used as an example of management difficulties that are associated with oceanic species. Problems associated with jurisdiction and institutional arrangements are coupled to significant levels of biological uncertainty and restricted management options, as well as to management concerns associated with the human domain. The case is conceptualized as an interaction between the human and more general ecological spheres, mediated by the history of the relationship between humans and the species in question. Two routes to regulation are presented, dealing respectively with the human and ecological aspects. Of particular significance is the idea that both types of information are necessary to maximize utility to both the human user and the Whales.Results from an ongoing study of recreational use are presented to indicate some of the variables that have emerged. These are to be interpreted within current resource management infrastructure to create a tenuous situation. The unfortunate logic that results from this study is that if Killer Whales (a high-profile species) in Canada (a well-endowed nation) have not warranted more substantial protection, then the outlook for less well-known marine species in areas of the world where resource management priorities involve more direct survival concerns, is not optimistic.
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