The deer are everywhere: strolling 30 deep through the pastures off North Road, blithely grazing Nat’s Farm field in West Tisbury, and bounding throughout the Island on streets, driveways and occasionally through windshields. They are gorgeous animals, what biologists delightfully call “charismatic megafauna.” But biologists have another term for the Island’s relationship with deer: beyond carrying capacity.

At a population density of 50 deer per square mile, the Vineyard is a virtual Tokyo of even-toed ungulates. And with hunting season here, many hunters, conservationists and concerned citizens hope to cull the population to a manageable level. But it is unlikely that they will do so without opposition.

Since Columbus Day much of the Island’s private and public land has been open to that most ancient and highly-skilled sportsman, the bow hunter. Bow hunting is expected to hit high gear by the end of next week when the rut begins. The rut is a period of the year when white-tailed deer are flooded with hormones compelling them to find love at any cost. Like us, this often makes them more reckless, aggressive and willing to take chances, whether this means imprudently crossing a road or not displaying their characteristic skittishness around hunters.

The start of the season is an ideal time to go hunting says Steve Purcell, owner of Larry’s Bait and Tackle Shop. “The deer aren’t as spooked yet and you can get closer shots. The deer are still moving slow right now though, since there are a lot of acorns in the woods and food to eat, so they’re not traveling like they usually do, but once the rut starts they’ll all start running around crazy,” he said.

Bow season runs until Nov. 21 and is followed by shotgun season, which begins on Nov. 29 and runs for two weeks, ending on Dec. 12. This is followed finally by antique firearms or muzzleloader season, which runs from Dec. 14 to Dec. 31.

Hunting is allowed anywhere on the Island where it is not expressly prohibited. That includes private property unless no hunting signs are conspicuously posted on the premises, although hunters may not hunt within 500 feet of a house. Violations of this prohibition are the most frequent hunting infractions Island environmental police officer Matthew Bass encounters.

“We have some pretty thick vegetation, and whether it’s intentional or not, people all of a sudden will come out of some very thick brush and be right next to somebody’s house. People in the house will then usually call us or the town police,” he said.

He said this kind of conflict with homeowners is becoming increasingly common,

“The area [for hunting] is getting smaller and smaller as more houses and developments are popping up. There are some traditional hunting areas where people have hunted for a long time, then one year they come back and there’s a house there now, or it’s somebody else’s property now who doesn’t want to have hunters around,” Mr. Bass said.

According to the Abstracts of the 2009 Fish and Wildlife Laws, this poses a major ecological problem:

“Hunter access remains one of the greatest challenges [to controlling the density of deer populations]. In a highly fragmented landscape with high human density, deer find small patches of habitat that act as refuges and are often left unchecked. Providing hunters with access to huntable lands in their communities is key.”

Higher densities of deer are problematic for a number of reasons, not least of all for providing a profitable vector for tick-borne illnesses, which have reached epidemic levels on the Island in recent years.

As a result, some conservation areas are now opening up their lands to hunting. Tim Boland, executive director of the Polly Hill Arboretum in West Tisbury, allows a small group of hunters on arboretum property in an effort to protect the biodiversity of the plants, which he sees as under threat from the overabundance of deer,

“What we see around the Island when we do our work monitoring rare plants that’s a little disheartening is that things are really being over-browsed, in certain instances resulting in local extinctions,” Mr. Boland said.

Among the plants threatened by the deer population Mr. Boland cited terrestrial orchids, false foxglove, and blazing star.

“What’s a real warning sign to me,” he said, “is that I’ve been to places where deer numbers continue to rise and in every instance there’s a relationship in the drop of overall biodiversity of plants as well as in the associated animals. Farmers and coyotes traditionally kept these populations in check and I don’t propose bringing back coyotes, but as the Island becomes more suburban we need a way to manage these numbers.”

But the expansion of hunting on conservation lands has not been without its controversy; a recent decision by Sheriff’s Meadow to allow hunting on two of its properties drew sharp criticism from the contributing editor of this newspaper.

But Mr. Bass said hunting is a form of conservation and that it is unhealthy for the deer herds to live in such high densities.

Three years ago shotgun season was extended from one week to two in response to an alarming increase in Lyme disease and other tick-borne illnesses, but some hunters do not feel the measure goes far enough and would like to see an additional hunting period in February.

Mr. Purcell said he has noticed little difference in the deer population since the extension of shotgun season. A drop in the deer harvest to 460 animals officially reported in 2007, down from 622 the year before, led many to believe that the extension of the hunting season was having a measurable impact. But last year’s harvest saw 696 animals taken, and this year there is a strong start as well.

“Last year we checked in 149 deer,” said Mr. Purcell whose shop sells doe tags and serves as an official check-in station. “This year we’re already at about 65 and it’s just starting to pick up.”

Mr. Boland said he understands why people have an emotional response to the killing of deer and empathizes with their cris de coeur.

“I completely understand it, deer are beautiful animals but at the same time, diversity is beautiful too,” he said. “The insects that are rare, the moths and beetle species that we have are unique and beautiful. I kind of think it’s more because deer have eyes. It’s harder to think of killing an animal when those beautiful eyes are looking at you.”