There are some persisting myths about the Vineyard — such as the notion that this is an easy place to ride a bicycle, that all Islanders know a ketch from a yawl, grow their own tomatoes, think nothing of picking up hitchhikers or picking off ticks, and most important, own at the very least one dog. Maybe two.

And that last one is the truest. Island dogs are omnipresent — and that doesn’t include the little pups that get carried around in summer purses like fluffy accessories. Island dogs are big, scruffy mutts and mix-and-match labs, retrievers, shepherds, terriers, the working breeds with names like Tashmo, Chappy or Max. They sit panting in open back trucks and on boat decks. They wait patiently for their owners outside Stop & Shop, Cumby’s and the post office. They docilely lope along on fishing trips, and on hikes through the woods.

While the lives of off-Island dogs intersect with their owners, the lives of Vineyard dogs are intertwined with their owners. In purpose and practice, their routines are woven into ours. We are conjoined.

Vineyard Haven harbor master Jay Wilbur and his golden retriever, Marlin, were inseparable. “He was a man about town,” Mr. Wilber says of Marlin. “He would go into Our Market, walk over to where the dog food was kept, and grab a can of Alpo. The Vineyard was like that back then . . . . The Vineyard has a calming affect on dogs. They’re not walking on sidewalks with traffic all around.”

It is with casual grace and nonchalance that Island dogs claim their entitlement. Like Marlin, most go everywhere and do everything with their owners short of voting and taking out a library card. They are the drooling regulars outside morning coffee klatches at Conroy’s, Your Market and Alley’s. Our turf is their turf, and they have come-and-go privileges. They’ve learned to expect the treats they get at gas stations and drive-thru banks, and the water dishes that are set out for them outside Island stores. They go to work with us — just call an electrician, carpenter or plumber and you’ll meet an Island dog.

Jackson and Mary Kenworth, the owners of State Road restaurant, have two “very social” Irish-bred Jack Russells, Berto and Daphne. “We refer to them as “restaurant dogs,” Mr. Kenworth says. “They are with us all the time. We work 50 hours a week and they come to work with us, staying in the office. And when we need to take a break, they take a walk outside with us . . . They have become part of our lives. They love us and we love them. They’re part of our family.”

Mr. Kenworth explains that he grew up in a small town in Illinois and had an Irish setter. “A dog was a pet, a responsibility,” he says.

Mulligan, the Gordon setter of Island native Kerry Scott, is also thought of as family. The owner of Good Dog Goods, Ms. Scott bred the setters. “Dogs have a way of working magic . . . and the same reasons I live here are the same reasons the dogs are glad to share my life: the beaches, the woods, the conservation lands and the staggering beauty of the place.”

Fan Ogilvie, a longtime horsewoman, breeds Irish Jack Russells. It was from her that the Kenworths got their two dogs. (“How could we break up a set?”)

“I think Island dogs are different from off-Island dogs in the same way Island people are different from off-Island people,” Ms. Ogilvie says. “We are able to deeply identify with the land and the sea. My dogs (Robin and Murphy) are the luckiest in the world,” she adds, describing the nine acres of yellow mustard that surrounds her home. “My dogs only know the smells of the outdoors. They’re not leashed, and they’re not cut off from their natural usefulness.” She recalls being on a walk through the woods when Murphy discovered a snake on the path and quickly tossed it away from them. “Off-Island dogs become what their owners want them to be,” she says. “We let our dogs out 10 times a day and they are allowed to express their working nature.”

And Mr. Wilbur has no doubts as to the impact a dog can have on its owner on this little Island. He credits his golden retriever with introducing him to his wife, Beth.

“He was passed on to me by a friend whose relationship had just broken up. This girl saw me walking with Marlin, came up to me and said, ‘That’s my dog.’ It seems my friend had once told her she could have him.” Solution? “She and I started dating.”