Cassin’s auklets (Ptychoramphus aleuticus) are tiny seabirds that build their homes in small burrows. Although the species is filed in the “least concern” category, the number of members in some of the populations has dropped.
A team of seabird experts has been documenting this rather mysterious event since fall. The scientists reported to have identified a total of 1,200 Cassin’s auklet bodies washed ashore. Executive director of the University of Washington’s Coastal Observation and Seabird Survey Team (COASST) Julia Parrish believes that what they found is just a fragment of the total number of dead birds estimated to be around tens of thousands.
It is a known fact seabirds can lose their lives during rough winters and especially when hit by powerful storms. This, however, does not explain the “massive die-off” that is currently unfolding.
According to Lindsay Adrean, Wildlife biologist at the Oregon Department of Fish and Wildlife, most of the Cassin’s auklet birds died of starvation, thus ruling out an oil spill or toxic reaction to food as possible cause.
But what made the birds starve? One explanation could be the fact that the birds had a very successful breeding season last year, with nearly all pairs laying an egg. Parish, who is also a professor of marine sciences, believes that some of the younger birds couldn’t find small fish to feed on during their winter flight towards south.
Another plausible cause would be climate change with the Pacific Ocean being warmer during this winter compared to recent years. This could result in small but effective changes in the food chain thus complicating the birds’ search for food. Violent storms could also interfere with the birds’ usual route making them fly in unfamiliar environment or interfering in their process of foraging.
Oregon Shores Conservation Coalition executive director Phillip Johnson considers that “the ocean, for some combination of reasons, is less abundant for their food sources.” Parrish, however, explained that the team couldn’t identify any other high death rate among other bird species living in the same areas as Cassin’s auklet. She continued by saying that normally, if one of the basic species in the ecosystem would start dying, all the other species would follow.
As the U.S. Geological Survey’s National Wildlife Health Center in Wisconsin is already examining the Cassin’s auklets carcasses, a cause for the mysterious death should be annuonced in the near future.
Image Source: Wikipedia