WINNIPEG — While Canadians have watched the Gulf of Mexico oil spill unfold from the safety of their living rooms, any number of the country's birds won't be so lucky as to escape the environmental catastrophe.

Experts say many species of water and shore birds that breed in Canada will soon be landing in oil-contaminated waters in the Gulf, where they stop on the way south.

And the impact on those species that make contact with the oil could be catastrophic.

Birds such as the white pelican, the common loon, the western grebe and the great blue heron might be among the casualties of the spill.

Ted Cheskey, manager of bird conservation programs for Nature Canada, said 40 to 60 species of water-dependent birds are starting to head to the Gulf area, including ducks, pelicans, gulls, herons and sand pipers.

"We're talking about possibly tens of millions of birds from Canada," Cheskey said. "For some birds for sure it's a one-way trip, they won't be coming back."

Cheskey said we might start seeing the impact of birds killed by the spill in the next few months and for years to come. And though nothing is certain, it's not looking good.

"I hope I'm wrong," said Cheskey, who has been bird lover since childhood. "It's hard knowing so many birds are going there, flying to their deaths. It's hard to talk about this but on the other hand I know it's a story that's not being told."

The loss of bird species could have unpredictable and unexpected effects on ecosystems and natural resources we all depend on, said Dr. Nicola Koper, ecologist and assistant professor in the Natural Resources Institute at the University of Manitoba.

"This oil spill is so devastating it's hard to comprehend what it could do to North American species," Koper said.

"I'm sure all of us are really happy it's not happening in our own back yard," but that doesn't mean we won't feel the spill's effects, she said.

"Birds are part of an ecosystem. When you remove a significant portion of that ecosystem, it can change that ecosystem in ways we can't predict very well."

This means humans could be out of luck if an ecosystem falls off-balance, affecting fish populations people depend of for their livelihoods, for example.

Koper said it's important for Canadian policy-makers to take the devastating event as a warning and to be cautious with the country's underwater drilling policy to avoid a similar event in Canada.

"We need to look after our own back yard to ensure this type of disaster doesn't happen here."