The Atlantic puffin, with its distinctive colorful beak and upright posture, is a beloved symbol of Iceland during the summer months. These seabirds gather in vast colonies along the country’s rugged coastlines to breed and raise their young. As autumn approaches, however, the puffins disappear from their breeding grounds, embarking on a long journey to unknown oceanic locations.
Their Mysterious Wintering Grounds
Icelandic puffins do not remain near their breeding colonies during the harsh winter months; instead, they disperse widely across the vast expanse of the North Atlantic Ocean. Recent advancements in tracking technology, such as miniature geolocators and satellite tags, have allowed scientists to shed light on these distant journeys. Data from these devices reveal that some Icelandic puffins travel thousands of kilometers, reaching areas as far west as the Grand Banks off Newfoundland. Other individuals venture into the open waters between Iceland and Greenland, or even further south to regions around the Mid-Atlantic Ridge. These findings indicate that puffins do not congregate in a single wintering ground but rather spread out over a considerable oceanic area.
Survival Strategies at Sea
Puffins possess specialized adaptations that allow them to endure months in the challenging conditions of the open ocean. Their dense, waterproof plumage provides insulation and buoyancy, protecting them from the cold North Atlantic waters. They are expert divers, using their powerful wings to “fly” underwater in pursuit of food. Their winter diet primarily consists of small schooling fish like capelin and sand eels, along with various marine invertebrates found in the upper water column. During the non-breeding season, puffins typically lead a solitary existence. This solitary foraging strategy helps them find sufficient food resources in the vast oceanic environment.
The Driving Force Behind Migration
The primary motivation for Icelandic puffins to undertake such extensive migrations is the scarcity of food resources around their breeding colonies during the winter. As the colder months set in, the small fish and marine invertebrates that constitute their summer diet become less abundant or move to deeper waters near the coast. Furthermore, the increasingly harsh weather conditions in the North Atlantic, including severe storms and freezing temperatures, make foraging near land particularly difficult and energetically demanding. Migration allows puffins to escape these unfavorable conditions and access more plentiful food sources in the open ocean.
Conservation Challenges in Winter
Puffins face several threats during their time in the open ocean. They are vulnerable to environmental disasters such as oil spills, which can coat their feathers, compromising their waterproofing and insulation. Entanglement in fishing gear, known as bycatch, poses a significant risk as they dive for food. Climate change presents a growing concern, impacting the distribution and abundance of their primary food sources like capelin and sand eels due to changes in ocean temperature and currents. Plastic pollution emerges as a threat, as puffins may ingest plastic debris or become entangled in larger pieces, affecting their health and survival. These challenges highlight the importance of protecting the marine environment where puffins spend a significant portion of their lives.