AC20 Inf. 22 Conservation and Management Status of Spiny Dogfish Sharks (Squalus acanthias):

• Main Authors: Sonja Fordham, Iucn Shark, Specialist Group
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2004
• Subjects: Pacific; New Zealand; North Atlantic; Northeast Atlantic; spiny dogfish; Squalus acanthias
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.232.2690; http://www.flmnh.ufl.edu/fish/organizations/ssg/E20i-22.pdf

The Spiny Dogfish, Squalus acanthias, is a small shark found in temperate waters worldwide, where it is or has been important in commercial fisheries. It is exceptionally slow-growing and long-lived and therefore especially prone to rapid over-exploitation and long-lasting depletion. The sustainability of Spiny Dogfish fisheries is further hampered by the tendency for directed fisheries to target large, mature females. Reproductive biomass in the Northwest has declined by 75 % in the past 15 years and total biomass has fallen by 95 % in the Northeast Atlantic since fisheries began over one hundred years ago. Demand for Spiny Dogfish meat, primarily from Europe where depleted stocks may no longer meet market demand, is driving targeted fisheries around the world, none of which are effectively managed. Spiny Dogfish fins also enter international trade for use in shark fin soup. There are no regional or international management measures in place for Spiny Dogfish. Biology The Spiny Dogfish is a temperate, cosmopolitan species with principal populations found in the North Atlantic, the eastern South Pacific, the South Atlantic off South America, the Cape coast of South Africa, the southern coasts of Australia and New Zealand, and the North Pacific. Although they are highly migratory, little mixing occurs among populations. Spiny Dogfish travel in large schools, segregated by size and sex. They are found from the intertidal zone to depths of 900m. Usually coastal and demersal, they migrate north and south as well as nearshore and offshore in 7–15 o C water (Compagno 1984). Spiny Dogfish are very long-lived. Individuals in the Pacific are thought to grow more slowly and larger than those in the Atlantic (Nammack et al. 1985). Life history characteristics are summarized below. Smith et al. (1998) found Spiny Dogfish to have the lowest intrinsic rebound potential of 26 shark species analyzed. These factors, combined with the tendency of fisheries to target the reproductive females (due to their large size), make the ...