New efforts to help Buffalo's common tern colony will be installed later this summer, but biologists also fear the birds will be impacted on their migration south by the oil spill in the Gulf of Mexico. (Sharon Cantillon / Buffalo News file photo)
BUFFALO -- Biologists have helped nurture the common tern colony in the Buffalo harbor and the Niagara River to become the largest nesting group of the small white birds on the Great Lakes.
But Connie Adams, senior wildlife biologist for the Department of Environmental Conservation, said the common terns could face a new man-made threat when they leave Lake Erie later this summer.
"I actually fear for them," Adams said in a recent interview, "because of the oil spill in the gulf."
The terns' long migration from Buffalo to Argentina will take them straight through the impacted waters.
"Our birds, when they leave here in late July and early August, will begin a migration that will take them right through the Gulf of Mexico," Adams said. "And we may see a decline in our tern population as a result of that. That will have far reaching repercussions to our bird life right here in Western New York."
The birds -- which Adams called an "important component of sea bird life in Western New York" -- have made gains in the region in recent years, but remain listed as a threatened species by the state.
More than 1,850 pairs of the small white birds made a home to nest along the breakwalls of the inner harbor last summer -- making it the largest tern colony on the Great Lakes, Adams said.
That's a few hundred more pairs, she said, than nested here in 2008.
Adams said gravel and other features added to the breakwall known as Donnelly's Wall have helped the birds contend with harsh lake environment.
"Their populations are really threatened by the fact that they have so few suitable places to nest," Adams said. "And as such, they are really sensitive to any sort of variation in the environment or any disturbance."
Terns -- smaller cousins to the sea gull -- have black caps, forked tails and a shrill call commonly heard in the inner harbor.
A barge placed in the breakwall area last year to improve the tern's nesting area, Adams said, was a temporary project that will not be replaced this year. Instead, additional efforts will be made later this summer to place gravel and make other permanent improvements to the nesting areas. Both initiatives are part of a habitat improvement project funded through a 2007 settlement for the relicensing of the New York Power Authority's Niagara Power Project.
"The barge was sort of a demonstration project to show that through the addition of gravel, you can not only slightly increase, but greatly increase the population of terns that are usually in a given area," Adams said, "because it's like a magnet to the terns. It draws them in."
Because the terns concentrate all of their nests in a small area, Adams said, that makes them "highly susceptible to disturbance." The gravel helps cushion the hard, unforgiving surface of the breakwall.
"Terns have really suffered through the years," Adams said, "And really, unless we provide more or less perpetual monitoring and maintenance of the colony, we would see a great decline in the tern population in Western New York."
Hear more from Adams and see the common terns in the Niagara River in this video: