Many of you will question the title of this article, especially in light of the recent hype and hysteria around shark bite incidents around the world, but let me explain. Two years ago I watched a National Geographic special called ‘Alaskan Killer Shark’. I expected the normal fear generating shark propaganda, but instead the show turned out to be one of the best natural history shark documentaries I have ever seen. It told the amazing story of a little known species of shark, the salmon shark (Lamna ditropis) found in the most unlikely place, Alaska. Inspired to learn more about this shark I contacted Dr. Ken Goldman of the Alaska Department of Fish and Game (ADF&G), the scientific advisor on the documentary and a pioneering white shark researcher. To my absolute delight Dr. Goldman invited me along on their next salmon shark research expedition, which is how I ended up in Cordova, a small fishing port in Alaska, a few weeks ago on my own journey ‘hunting’ down these extraordinary sharks.

Dreaming of Alaska my mind conjured up images of glaciers, grizzly bears and pines trees, but certainly not sharks, especially warm-bodied ones. Yet, the cold waters of the north Pacific are this species stronghold. Salmon sharks are close cousins of white sharks, and although a third smaller in length, they are superior in their thermoregulatory abilities, capable of maintaining an elevated body temperature up to 21 degrees Celsius higher than the ambient ocean temperature. Pretty cool for a shark! Currently salmon shark populations seem to be stable across their range according to Dr. Goldman and his colleagues; however, of some concern are the (currently) unreported catches in commercial seine fisheries and the effects of sport fishing which seem to be increasing in popularity.

Alaska is a country of extreme beauty. Picturesque landscapes disguise a harsh and unforgiving wilderness, but this powerful combination is a giant magnet for free-spirits and adventurers. Brown and black bears, moose and deer are your neighbours, and living side by side Mother Nature is non-negotiable. During a single short drive the landscape is constantly changing from sea, to wetland, to river delta, to snow covered mountains and glacier grand finales. The importance of the annual salmon migration is obvious the moment one arrives in Cordova with locals and tourists alike passionately casting their lines alongside the bears, sea otters, harbour seals, and bald eagles - all hoping to take home the ‘catch of the day’.

The aim of the research trip was to retrieve and redeploy tracking stations in Prince William Sound that monitor tagged salmon shark presence and furthermore to catch salmon sharks to attach acoustic pingers and satellite tags to study their migration patterns. The project is a collaboration between the Alaska Department of Fish and Game, Hopkins Marine Station, Stanford University and Virginia Institute of Marine Science. We managed to achieve the first objective and the tracking receivers reported five tagged sharks in the area just five days before our arrival. However, we didn’t manage to fulfill the tagging objectives as we didn’t encounter any sharks during our time there. We spent days searching for signs of hunting sharks and fishing for them, but didn’t see a single one. Such is the life of a shark scientist and while this was a disappointment for the team, it highlighted the need for a better understanding of the driving forces behind their movements, and the importance of the ongoing research. Next year the team will attempt the tagging again and I can only hope for another special opportunity to encounter these Alaskan “killer” sharks.

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