A piece of wooded land near our home is about to be developed. This will mean removal of some trees that are 200 years old. The woods is a remnant of the Big Woods that once covered much of east central Minnesota.

The owner cannot maintain the land, and so chooses to sell. That's understandable.

There about 30 acres of old trees there, a woods deeply shaded in the summer, an understory so thin that walking is unimpeded. I've spent a lot of time there; it's beautiful. It's not particularly birdy; old woods tend to be that way. It's heavy on woodpeckers, chickadees, and nuthatches. Owls have nested there, and Red-shouldered Hawks, I believe. Wild Turkeys are common, as are deer and coyotes.

Thirty acres could be called mostly edge. You can't walk very far into 30 acres before you come out the other side. The impact of edges on use by animals extends far enough into this woods that little of it is untouched. But five homesites, an access road, and driveways all create more edges, and will turn the entire piece into habitat dominated by edge. All of it will change.

The negative impacts created by edges, according to a study in New York state, bring decreased nesting near trails, altered bird species composition near trails, and increased nests predation by cowbirds, skunks, raccoons, and foxes using the clearings, trails, and roads as corridors. The study also showed that some species of animals are reluctant to cross openings, even to fly across openings. This reduces land available for nesting territory and foraging.

On the other hand, some species find edges attractive. Vegetation types change. There is more light and more rain.

Plus and minus.

Overall, though, with this change we lose more of a habitat type that is disappearing.

A recent article in "The New Yorker" addressed the environmental impact of roads ("What Roads Have Wrought" by Michelle Nijhuis).

She quotes Prof. William Laurence of James University in Cook, Australia, as saying: "Roads scare the hell out of ecologists. You can't be in my line of business and not be struck by their transformative power."

Nijhuis writes: "No matter the ecosystem — forest, prairie, patch of moss — the effects of habitat fragmentation are ruinous."

So, the woods change, the animals likely leave, and that's the way it goes.