JEFFERSON, N.H. — Driving along the edges the Silvio O. Conte National Fish and Wildlife Refuge, Dave Govatski slows to marvel at the flock of blue jays flying past and spots a woodpecker-like flicker darting through the pine trees.

That stretch of forest, wetlands and pasture in northern New Hampshire is part of a refuge that covers more than 37,000 acres of mostly former timberland that encompasses parts of Vermont, New Hampshire, Massachusetts and Connecticut. It is home to coyotes, bears as well as rare plants and fish species. But it is best known for migratory birds, with 275 species calling the refuge home.

The birds are a big reason that Govatski, a forester and naturalist, supports plans endorsed earlier this year by the U.S. Fish and Wildlife Service to significantly expand the reserve over the next 15 years.

The Silvio O. Conte National Fish and Wildlife Refuge comprises 36,000 acres in the Connecticut River watershed – mostly in New Hampshire but with smaller tracts in Vermont, Massachusetts and Connecticut. U.S. Fish & Wildlife photo

“These things are refueling stops for birds traveling long distances from South America up into northern parts of North America where they can rest and continue their journey,” Govatski said. “It’s like you are on a highway where you have a chain of rest stops where you can get gas and get food and not be harassed.”

But the scope of the expansion plan is now sparking opposition from the timber industry that fears the loss of lucrative logging sites. And officials in Vermont and New Hampshire have raised concerns that lands that could contribute to the tax rolls would be lost.

“The plan as I see it is a slow motion body blow to the working forest of Vermont and all those who earn their living harvesting forest products and processing them into lumber and into wood products that are part of their lives,” said Bill Sayre, co-owner of a lumber mill in Vermont and plan opponent.