EDMONTON - Alberta is under heavy pressure to strengthen its environmental standards as the fallout from the death of 500 ducks in a toxic wastewater pond gets stickier than the province's oilsands.

Images and stories of the dying waterfowl have been bobbing up on news outlets and blogs around the world, prompting even Prime Minister Stephen Harper to suggest that the dead ducks have tarred Alberta's and Canada's international image.

"I'm not here to make any excuses for the particular event that occurred over the last few days. It is a terrible event. It is not going to do anybody's image any good,'' Harper said in Edmonton on Thursday.

"And you know I think the premier's government and our government are obviously prepared to work together to make sure that industry fulfils both its existing obligations and any new obligations that we think are necessary.''

The flock of ducks landed earlier this week on a Syncrude Canada Ltd. tailings pond near Fort McMurray.

Such ponds, which contain billions of litres of water left tainted after being used to remove oil from sand in the area, sit along the flyways birds use to migrate to and from northern nesting grounds.

The Syncrude pond is usually ringed with noise-making cannons that are supposed to scare birds away, but the sonic scarecrows were not in place earlier this week.

Bruce March, the new CEO of Imperial Oil -- which has a 25 per cent stake in Syncrude -- called the death of the ducks a tragic event and suggested the corporation will change its procedures to ensure it isn't repeated.

"I'm deeply disappointed,'' March said in Calgary.

"It's something that hasn't happened in a very long time, but (there are) really no excuses for what happened. It shouldn't have happened and we're deeply upset, doing all we can do to change work processes and change procedures to prevent it from occurring in the future.''

As Harper and March grabbed the issue, Alberta Premier Ed Stelmach appeared to try to dodge the dead-duck flap. He called the deaths tragic and promised to get to the bottom of what happened. But he qualified his remarks by telling reporters that wind turbines claim far more birds that oilsands tailings ponds.

"Just to give everyone a bit of perspective ... it's well known that on an annual basis, the minimum number of birds killed by wind turbines is around 30,000,'' Stelmach said.

The province has acknowledged that the furor surrounding this story has dealt a blow to Alberta's $25-million campaign to sell its booming oilsands as eco-friendly.

News organizations began reporting on the story at the same time that Alberta's deputy premier was in Washington, D.C., to dispel what the premier has called the "myth'' being spread that the oilsands are an environmental disaster.

Aboriginals who live near the Alberta oilsands site where the ducks died have called for a federal inquiry on how to protect migratory birds, fish stocks and species at risk.

Chief Vern Janvier of the Chipewyan Prairie First Nation said his people are upset and alarmed at the federal and Alberta government's negligence in protecting the environment.

He said Ottawa has legal and constitutional obligations to provide such protection, based on treaties it has signed with aboriginal people.

"The governments wish us to believe they are monitoring environmental impacts towards ensuring the protection of our environment, but we have repeatedly witnessed their neglect of their duties,'' Janvier said.

"We demand that the First Nation governments have an independent role in monitoring the activities.''

Chipewyan elder David Janvier said there should also be a moratorium on further oilsands development until new rules are in place to protect the environment.

Waterfowl experts such as professor Lee Foote of the University of Alberta also weighed in on Thursday. While the number of birds that die in tailings ponds is relatively low every year, Foote said over time the numbers could become significant.

"These mortalities from oil pits must stop,'' Foote said. "They could represent a long-term sink in the population that is essentially permanent unless addressed properly.''

American environmental organizations such as the Natural Resources Defence Council noted that the dead duck story was reported by news outlets including the New York Times, CNN, MSNBC, the International Herald Tribune, the Scotsman and wire services.

Groups that oppose the oilsands will use the story and the images to reinforce their lobbying efforts, council spokeswoman Liz Barratt-Brown predicted.

"This story is going to become an emblem of what is wrong with the tar sands.''

The global reach of the death of a few hundred birds in Alberta was not lost on the prime minister, who made a point of reiterating that his government plans to strengthen environmental enforcement across the country. Harper said the dead ducks provide yet another reason to follow through on the commitment.

"Part of our responsibility as an emerging energy superpower is to be good stewards of our environment and also to become world leading on the environmental side of the energy business,'' he said.