A new study from the journal Waterbirds states there’s an increasing amount of mercury occurring in birds in Alaska’s Arctic coast.
The Yellow-billed loons migrate to Asia from the Alaska Arctic plains every year. Mercury levels tested in these birds have doubled since a study in 1920 was released. The recent study says the methyl mercury in the Arctic is rising, but these loons are receiving the majority of the mercury when they travel overseas to Asia.
The diet of a Yellow-billed loon consists mostly of fish. The higher up the food chain, the more likely the organism is to ingest higher levels of mercury and other toxins.
Executive Director at the Biodiversity Research Institute David Evers says the researchers caught a sample of loons and tested their blood and their feathers.
“And a blood sample shows how much mercury is in their body from the last week or two. A feather tells us the mercury in the body over a year or a life time of the bird. And the objectives of the study were to look at the spatially, both on the breeding ground and the wintering areas, and also temporally, to look at mercury exposure over the past 100 years or so.”
Evers says the scientists have electronic tracers on the loons so they can be monitored from thousands of miles away. He says the birds near the North Slope don’t have high levels of mercury-- it’s when they travel for the winter to Asia that the loons pick up the mercury. He says birds with excess mercury in their system spend 10-15% less time incubating their eggs.
Evers says there are currently a few precautions nationally and even an international program undergoing to make these levels decrease.
“There is direct activities that can be carried out right now. There’s a new global treaty that was signed by the US and 100 countries, in October of 2013. In that global treaty, there are many ways to reduce mercury at local, global and regional levels including the mercury level emissions from India and China that appear to be landing in Alaska. Once that treaty is ratified by half the countries that signed on the clock starts ticking within the convention and the various stipulations go into effect.”
The study looked at 115 birds and eggs collected from 2002 to 2012 mostly from Alaska’s North Slope. There are roughly 3,000 yellow-billed loons in Alaska and the US Fish and Wildlife Service is considering placing the bird on the endangered or threatened species list.