“Forage fish” such as sardines, herring and other small schooling species form a crucial link in marine food webs. They feed on plankton and convert this abundant but tiny energy source into dense packets of protein and fat that sustain larger predators. Seabirds, marine mammals, and larger fish (including most species eaten by humans) depend heavily on forage fish for their own growth and reproduction.
Today, puffins in most parts of the world are protected by wildlife regulations and colonies are in wildlife reserves, but life at sea is more precarious. Puffins rely on forage fish for day-to-day survival and for feeding chicks, but the availability of that food is far less secure than the birds themselves. In particular, there are large-scale fisheries for important puffin prey, such as sand lance (aka sand eels in Europe), herring, sprat, capelin, anchovy and sardine which have historically created deficits in predator diets. Reduction in forage fish availability to birds may also arise from competition from fish and mammal predators that share forage resources, and when forage fish stocks are diminished by ocean warming events, which are increasing in frequency.
When forage fish are overfished, the effects cascade through entire ecosystems. Declines in sand eel stocks in the North Sea, for example, have been linked to poor breeding success in seabirds such as kittiwakes and puffins. Similar concerns exist for capelin in the North Atlantic and anchovies in the North Pacific. Despite the ecological importance of forage fish, fishery managers often set quotas based primarily on maximizing harvest rather than maintaining sufficient prey for marine predators. Ecosystem-based management—accounting for the needs of seabirds, marine mammals, and larger fish—remains only partially implemented in many fisheries today.
What actions can you take to help make sure puffins find the fish they need to thrive? There is no simple solution. Management of forage fish stocks is a global issue, and many organizations take an active role in advocating for sustainable fishing practices that accommodate the needs of marine birds and mammals in healthy marine ecosystems. Here’s a few you can visit to educate yourself further about the role of forage fish in marine ecosystems, and see how you might contribute to their conservation.
FISHSEC The Fisheries Secretariat (Europe)
Marine Fish Conservation Network (USA)
National Audubon Society (USA)
OCEANA Protecting the World’s Oceans (International)
Oceans North (Canada)
