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Salmon sharks
Scientific name: Lamna ditropis
The salmon shark is in the lamnid shark family, along with the great white and mako sharks. All members of this group are endothermic; they are capable of elevating their body temperature above that of the surrounding water. Within this group, salmon sharks have the most impressive thremoregulatory capabilities. They can maintain their body temperature above 20 C in waters as cold as 2 C!
Salmon sharks range widely throughout the North Pacific Ocean, most commonly from 65° N latitude to 35° N in the west, and to 30° N in the east. These sharks are found in the transition zone and coastal upwelling areas, and occur in large aggregations in Alaska waters from spring through fall. They consume a wide variety of prey, including salmon, herring, sablefish and squid. Salmon sharks are caught incidentally in a number of fisheries and there has been some discussion about developing a fishery specifically for them. Given the low reproductive capability of this species, the sustainability of such a fishery is questionable.
Salmon sharks have been tracked with acoustic, Smart Position and Temperature (SPOT) and Pop-up Satellite Archival (PSAT) tags. They exhibit short-term site fidelity in coastal waters, surface residency and oscillatory deep diving, making them sound platforms for both geolocation and oceanographic profiling. Their surface residency makes them a perfect candidate for the fixed-fin SPOT tags that uplink data to the satellite when the shark is at the surface. Methods for capturing and handling salmon sharks have proven successful and large numbers can be obtained in Alaska during the summer months.