In an era when large swaths of pitch pines and scrub oak are routinely cleared to make way for new homes, it would be easy to think of the Vineyard as rapidly losing its woodland character.


In fact forest acreage on the Island has grown over the past 100 years as the Vineyard has shifted from an agricultural-based society of farmers and shepherds to a resort community of second homeowners and seasonal residents.

By some estimates, Island woodlands have increased 20-fold since the late 19th century.

“If you went back in time 100 years you might not even recognize the Vineyard,” said Allan Keith, a Chilmark resident and well-known naturalist and ornithologist. “There were spots in West Tisbury and Chilmark where you could stand and practically see clear across to Edgartown or Vineyard Haven . . . the whole Island was basically one open field.”

The slow evolution from farms and open fields to forests and neighborhoods also has driven out some species of plants and animals, while inviting the return of others that have not been seen here since before colonial times.

Mr. Keith estimated that in the 1950s at least 75 per cent of the Vineyard was open pastures and grasslands with only small patches of low scrub oak.

This abundance of grasslands provided a haven for certain species of birds like the upland sandpiper, vesper sparrows, grasshopper sparrows, killdeer, spotted sandpipers and meadow larks, he said. But with the loss of open fields, many of those species are now gone from the Island, and have been replaced by other woodland species like Baltimore orioles, rose-breasted grosbeaks, black and white warblers, red-eyed vireos and scarlet tanagers, Mr. Keith said.

“It’s a trade-off . . . [the Vineyard] has lost some species with the change in habitat only to see others return or come here for the first time,” he said.

The change in landscape has also affected the population of mammals and larger predators on the Island. Much earlier, before colonial settlers arrived, Mr. Keith said, the Island had a wider range of mammals like red and gray foxes and beavers in addition to raccoons and skunks. But those populations were decimated when they lost their natural habitat or were trapped by colonists who killed them for meat or pelts.

By the late 1800s, Mr. Keith said, many species of mammals — including skunks and raccoons — had disappeared from the Vineyard.

“Around the turn of the [19th] century, Vineyard skunks could fetch as much as $1 for a single fur, which was big money back then. There was a recession going on and people were looking for ways to make money, and since the Island was almost totally deforested just about anyone could go out and find themselves a skunk,” he said.

But as woodlands have grown up in old pastures in recent decades, skunks and raccoons are now flourishing again.

Augustus (Gus) Ben David 2nd, a noted Island naturalist and wildlife expert and former director of the Felix Neck Wildlife Sanctuary, said the return of woodlands has been accompanied by an increase in birds like the Cooper’s hawk and the great horned owl. He said the decline in farmland and increasing forest growth is occurring all over New England, which has led to population shifts for larger animals like black bears and moose, which now must coexist with suburban home developments.

Asked if the changes on the Vineyard are good or bad, Mr. Ben David takes a larger view.

“It’s all cyclical . . . it’s all related. In the case of the Vineyard, all those animals that once lived in the forest are making a comeback while others are disappearing. Meanwhile we’ve lost all these old farms, but we have all these trees,” he said.

Matt Pelikan, director of The Nature Conservancy’s Massachusetts Islands Program, takes a similar view that the changes in plant and animal populations may be part of a larger cycle. He said the population of certain types of butterflies here has shifted over the past century. There was once a thriving population of sulphur butterflies that were closely associated with the agricultural landscape, but their numbers have fallen dramatically in recent years.

Conversely, some woodland butterflies like the cabbage white, the red-spotted purple and the eastern tiger swallow have likely benefited from the return of the forests.

In addition to the change in landscape, other environmental factors can have an impact on the Island ecosystem, Mr. Pelikan said. Some species of butterflies have been recorded on the Island later in the year than usual, perhaps a by-product of warmer temperatures and global warming, he said.

“Other species are actually emerging later in the year than usual, in some cases to an unprecedented degree,” he said.

Mr. Pelikan warned that even slight changes can have a dramatic impact on the ecosystem.

“There are a lot of concerns around the globe about the changing phenology — the cycle when certain things happen in nature at a specific time of year. In the case of butterflies, some species now take longer to hatch and begin to fly later in the season, which in turn affects certain types of plants,” he said.

Felix Neck director Suzan Bellincampi said she has observed changes in animal behavior in recent years. The annual return of the spring peepers — or pinkletinks, as they are called on the Vineyard — seems to come earlier each year, she said, as does the return of the majestic osprey, which many view as a harbinger of spring.

In recent weeks, Ms. Bellincampi said, a milk snake was spotted molting in a closet at Felix Neck headquarters, and a red-backed salamander was spotted during a nature walk — both rarities for this time of year. She said the phenomenons are hard to explain.

“You never know with nature . . . the only thing you can predict with nature is that it’s unpredictable,” she said.