North Atlantic Killer Whales; past, present and future
Killer whales are one of the ocean’s top predators, including the waters around the UK. Climate change is opening new habitats and potentially offering new prey for killer whales, particularly in the Canadian Arctic. With their potential to have population level effects on prey, these top predators have the ability to shape this rapidly changing ecosystem. On the other hand, climate change will likely lead to shifts in distribution and potential availability of other prey that some killer whale populations seem to depend upon, such as Atlantic herring. Although our understanding of North Atlantic killer whale ecology and evolution has come a long way in the last twenty-five years, there are still large gaps in our knowledge of the extent of geographical movements, prey preferences and population viability. Without such information it is impossible to critically assess the threats faced by killer whales and their conservation status. Collaboration between researchers and a long-term consistent monitoring effort will be critical to effectively assess these issues. The ecosystems of the North Atlantic will likely be highly dynamic during the next twenty-five years, and both North Atlantic killer whales and the researchers that investigate them will need to adapt to these ongoing changes and challenges.
Recently a workshop held at the European Cetacean Society conference in Galway (Ireland) reviewed the state of the art of killer whale research in the North Atlantic and selected presentations from this workshop were published in a special section of the Journal of the Marine Biological Association of the United Kingdom. Bringing together research from all corners of the North Atlantic this special section showed that research in the North Atlantic has come a long way. Topics included distribution patterns, population abundance, prey preferences and morphological variation to name a few and revealed the diversity of killer whales found in these waters. The research, however, also identified populations at risk requiring immediate conservation action. The West Coast of Scotland and the Strait of Gibraltar are particular areas of concern, where killer whale numbers are decreasing and birth rates are too low to sustain the populations in the long term.
Dr Andy Foote
University of Copenhagen