In this May 9, 2010, file photo, oil-stained cattle egrets walk the deck of a supply boat in the Gulf of Mexico, off the Louisiana coast. (Gerald Herbert/Associated Press)A Memorial University professor says migratory birds that return to Newfoundland and Labrador each year are being killed by oil spilling into the Gulf of Mexico.

Every spring tens of thousands of white gannets circle the bluffs of the Cape St. Mary's Bird Sanctuary, southwest of St. John's. There are also large gannet colonies in Quebec. They come north to nest, lay eggs and raise their chicks.

Many of them migrate from the southern U.S., where a BP well has been spilling thousands of litres of oil into the Gulf of Mexico since April 20.

"We know our birds are dying there," said professor and seabird researcher Bill Montevecchi.

"You know, we can feel the long reach of that oil spill in Louisiana, Gulf of Mexico, here in Eastern Canada. What we do know is that some of our gannets are being oiled and the birds I've seen [pictures of from the Gulf of Mexico] are so heavily oiled that they are going to sink in a day or two."

Bill Montevecchi is a bird researcher and professor at Memorial University in St. John's. (CBC)Montevecchi and other bird scientists are planning to attach satellite tags to some birds in Newfoundland this summer in order to track them and see how they fare when they return to the Gulf next fall.

"It seems to me it's just responsible to find out what's happening to our birds that are going back there from eastern Canada."

He worries birds that head south from Canada will land in oily water in the Gulf and die.

"The birds I've seen already, the most humane thing to do

'It's a total assault on their body'—Bill Montevecchi. bird scientist

would be euthanasia. They are so covered with oil there is no way they are going to survive. It's a total assault on their body. It shuts down their oil glands. They ingest it. You can clean them on the outside but they are dying on the inside," said Montevecchi.

He said there is also fear that the oil spill in the Gulf may harm marine mammals, such as humpback whales, that come to Eastern Canada annually.

The Cape St. Mary's Bird Sanctuary is a popular tourist attraction in the spring and summer months when gannets are there.

"It's really quite a tragedy that I hadn't contemplated until we arrived here," said John Carol of Milton, Ont., who was at the sanctuary on Wednesday. "What it really points out is the international implications of a disaster thousands of miles away that has implications for Newfoundlanders or tourists like us who come to visit this beautiful spot."