Conservation
Toxic Mementos Left Behind in the Arctic

submitted by Kelly Liao

“When one tugs at a single thing in nature he finds it attached to the rest of the world.” — John Muir
The "Silent Spring" of Rachel Carson continues to flow. The effects of human impact upon the environment can be observed as near as our backyards or as far away as the Arctic.

The Arctic may be devoid of industry and agriculture, but it is slowly turning into a pollutant dump just the same.  The phenomenon is known as the grasshopper effect, because the contaminants — including persistent organic compounds like PCBs and DDT — tend to evaporate in the more temperate zones where they are produced, migrate on air currents and condense in the colder polar region.

"What we've been seeing over the past 15 years is that the Arctic is essentially acting as a depository for many industrial chemicals," said Jules M. Blais, a biology professor at the University of Ottawa.  But the distribution of these contaminants in the Arctic is not uniform.  "Some places have a lot and others a little," Dr. Blais said.  He and colleagues have now provided an explanation:  seabirds, they write in the journal Science, can concentrate the contaminants in a small area.

The researchers studied the effects of a colony of Northern Fulmars on Devon Island in the Canadian Arctic.  About 20,000 of the birds live along 800-foot cliffs, above a series of ponds.  The birds eat fish, squid and other food from the ocean, and their wastes are washed down the cliffs into the ponds.  All the nutrients in the wastes make the nearer ponds teem with life — mosses, insects, even small birds — in what is otherwise a bleak landscape.  The seabirds, Dr. Blais said, "support an entire ecosystem below where they are nesting."  But analyses of pond sediment show that the seabirds are also passing on DDT, mercury and other contaminants.  Ponds closer to the nests had more of the toxins.

The birds are eating relatively high on the food chain, Dr. Blais said. "The things they are eating have bioconcentrated the chemicals," he said.  "Essentially, the birds are funneling a large mass of marine carnivores like fish and squid into small areas where they are nesting."  Dr. Blais said that the fulmar colony was fairly typical of seabird colonies in the Arctic, so it is likely that there are many other areas with concentrations of contaminants.  "The concern is that this contamination is happening precisely in areas that are focal points for biological activity in the Arctic," he said. -- Henry Fountain, New York Times, July 19, 2005
— Henry Fountain, The New York Times, July 19, 2005

Wings Over Dutchess, January 2006

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