Coral Harbour (Aug 02/06) - An outbreak of avian cholera has devastated the Canadian Arctic's largest colony of common eider ducks near Coral Harbour on Southampton Island.

Scientist Grant Gilchrist of the Canadian Wildlife Service said the situation has escalated dramatically in the past year.

About 300 birds died in 2005, but that number has increased to more than 1,500 in 2006. Avian cholera is a naturally occurring disease, but it's uncommon in the North, said Gilchrist.

"We're not sure why it's so rare... but it may be the cold prevents it from persisting over the winter.

"The disease can be brought to the North by migrating birds and, once established, it generates an epidemic like we're seeing now on Southampton Island."

Most worrisome about the cholera epidemic is the toll it has taken on the female eider population.

The hens sit on their eggs in nests, which puts them close to each other on the same ponds where the disease is spread.

Male eiders leave the island a few days after mating with the females.

Since eiders reproduce slowly due to their relatively long lifespan, the epidemic could devastate the colony's breeding population.

The outbreak, though, is still fairly isolated and has yet to spread across Nunavut, Gilchrist said.

The wildife service is working with people in a number of communities to try and track where cholera has occurred.

"It's been more hot spots than a sweeping epidemic across the territory."

One of the worst hot spots is near Coral Harbour, home to one of the largest colonies in the country, he said.

Science has no way to slow the disease other than to burn the dead carcasses.

That can be hard for the short-staffed wildlife service to accomplish in remote Northern communities.

Other bird species at risk of contracting the disease by feeding on dead eiders are glaucous and herring gulls, the raven and jaeger.

Avian cholera is very different from avian flu and cannot be passed onto humans.

However, Gilchrist strongly cautions against the consumption of any bird that may have been afflicted with the disease.

"If, by accident, someone ate one, we're not worried about the disease being transmitted to them.

"But it's never a good practice for humans to eat sick animals or birds."

An average of 4,000 hens nest on Southampton Island, which is 800 metres long and 400 metres wide.

Wildlife officers have counted 350 herring gulls and 30 glaucous gulls scavenging dead carcasses, making the island a gruesome sight with more than one-third of the eider colony dead.

The eider is one of the most heavily harvested sea birds in the Arctic, hunted for its meat and eggs.

The birds that breed in Nunavut are also heavily harvested in Atlantic Canada and western Greenland.

Gilchrist said there are regulations governing the harvest, but they don't assume there's an outbreak.

"If cholera were to become a persistent disease for these birds, as it is in southern Quebec, it would have the potential to heavily influence Inuit harvesting in Nunavut.

"I'm not suggesting that's going to happen because this is an isolated and, hopefully, rare incident."

Eiders breeding in the Gulf of St. Lawrence are hit with cholera outbreaks every few years, he said.

"It's one more pressure on a long-lived bird that can't rebound quickly from these things."

The wildlife service has sent carcasses to southern laboratories for absolute confirmation that cholera is the cause of the outbreak.

Once the eiders leave over the next few days, there won't be any birds left on the island except herring gulls.

At that point, a crew will begin counting the bodies.

The crew will incinerate the carcasses and take water samples to determine the level of cholera on the island.

"We'll be back on Southampton Island next year to see if it happens again," Gilchrist said.