image: This is a whiskered auklet. view more
Credit: Ian Jones
A new study from The Auk: Ornithological Advances presents some of the best evidence that Whiskered Auklets are an outlier in the auklet family by not migrating and instead staying close to "home" (their breeding colonies) year-round. Most migratory birds lead two opposite lifestyles in the same year. During the breeding season a bird's location is constrained and their habits are repetitive given a nest full of chicks that require food, warmth, and protection. For some birds it is the only time they congregate or otherwise come together. Comparatively, during the non-breeding season their only true task is to survive. Whether migratory or residential, as long as the bird makes it back to the breeding grounds to reproduce, they can go almost wherever they want. Whiskered Auklets are consistent through the year though and don't wander far at all.
Carley Schacter and Ian Jones of Memorial University of Newfoundland used light-based archival geolocation tags on Whiskered Auklets in Buldir Island, Aleutian Islands, Alaska, to determine the locations of their full annual life cycle. The data they collected corroborated what researchers have long suspected. This species is unique in the auklet family for not migrating at all. Most seabirds roost on the water at night, but Whiskered Auklets stay in the vicinity of the breeding colony year-round and consistently return to roost at night on land. Such behavior may not only be unique to auklets, but to the entire seabirds group. How could this unusual adaptation have come about? Whiskered Auklets capitalize on the foraging habitat close to their breeding colony which reduces metabolic costs. Given the influence of tradeoffs on animal behavior and life history strategies, this foraging area could be a large contributor to their residential behavior. But there are risks to this strategy as well. Lead author Carley Schacter notes, "While this non-migratory behavior is very interesting to us on a theoretical level, there are also important implications for the conservation and management of this most vulnerable of auklet species. Year-round residence near the breeding site (an area of high fishing and shipping traffic) makes Aleutian-breeding Whiskered Auklets even more exposed than previously thought to human threats such as oil/fuel spills and light attraction leading to fatal collisions with vessels. Their nocturnal roosting behavior also makes them especially vulnerable to introduced mammalian predators such as rats and foxes."
"The authors found evidence for an almost unique adaptation of a seabird in a remote, difficult-to-work-in, and isolated environment," adds Jeff Williams, Assistant Refuge Manager at the Alaska Maritime National Wildlife Refuge, who was not involved with this research. "We now know that Whiskered Auklets are particularly sensitive to human-caused disturbances (oil spills, light attraction, invasive species introductions etc.) and can incorporate this information into management planning."
###
Confirmed year-round residence and land roosting of Whiskered Auklets (Aethia pygmaea) at Buldir Island, Alaska will be available May 30, 2018, at http://www.bioone.org/doi/full/10.1642/AUK-17-235.1
Researcher contact: Carley R. Schacter, crs634@mun.ca
About the journal: The Auk: Ornithological Advances is a peer-reviewed, international journal of ornithology that began in 1884 as the official publication of the American Ornithologists' Union, which merged with the Cooper Ornithological Society in 2016 to become the American Ornithological Society. In 2009, The Auk was honored as one of the 100 most influential journals of biology and medicine over the past 100 years.