Potential for sustainable expansion of the dogfish (Squalus acanthias) fishery in the northeast Pacific

Spiny dogfish are one of the most abundant shark species and support major commercial fisheries. Because of their slow life history, including the longest gestation time among vertebrates, they are expected to be vulnerable to overfishing and slow to recover from depletion. Indeed, dogfish in the Atlantic have been declared overfished, and a petition to list them under the CITES agreement is currently underway. In the Pacific, on the other hand, there may be scope for the expansion of the current dogfish fishery. Here, we provide scientific information on stock structure and demographic parameters of dogfish, together with an analysis of the sensitivity of dogfish to exploitation. Genetic data suggested a deep phylogeographic split between dogfish in Atlantic / South Pacific and North Pacific, coinciding with major differences in life history between the two groups. Within the North Pacific, there was little evidence for genetic differentiation, though essentially self recruiting populations may still exist. Statistical comparisons of region-specific growth curves for females indicated differences in growth between dogfish in the northern and southern regions of the latitudinal range and between Puget Sound and outside waters of the open coast. As expected, slower growing and later maturin