Durkee’s General Store in Islesboro, Maine, located near the possible origin of the up-island spider, lets seekers of the giant arachnid know they're getting close. (Mimi Kirk)

My husband and I were about to embark on a long drive from Washington to a cabin on the Maine coast, just across West Penobscot Bay from Islesboro, a skinny, sparsely populated 13-mile-long island. Brian and I were ecstatic at the prospect of lolling about for seven days, but still I worried that we’d ultimately get stir crazy. So I was checking out the Wikipedia entry for Islesboro, thinking that a day trip to the island might be nice.

Scanning the entry, my eyes fell on the words “up-island spider.” Hmm. That sounds interesting, I thought, and clicked on the link. And wow.

The spiders, I read, are said to be unique to Islesboro. And huge — up to eight inches across with their legs splayed — with red eyes. “Some specimens are reported to be large and heavy enough to create audible footsteps in a quiet room,” I read with simultaneous fascination and horror.

Of course, the entry was also peppered with caveats. Most sentences describing the arachnid employed phrases like “thought to be” and “said to be.” I wondered: Did this spider actually exist?

I would go to Islesboro, I decided, and find out.

If you go: Islesboro, Maine

Brian is used to my compulsive schemes to see bits of Americana or eccentricity, so he was patient with me, even enthusiastic. He discovered that Portland — two hours south of Islesboro — is host to the International Cryptozoology Museum. He figured that with its focus on “hidden animals” that “remain unverified by science,” such as the Loch Ness Monster or Bigfoot, it would whet our appetites for hunting down the up-island spider. Plus, we could ask museum founder Loren Coleman what he knew of the elusive creature.

Coleman met us at the entrance to the museum on a side street in downtown Portland and cheerfully took $14 for two tickets. He has a professorial air, with a full head of gray hair, a gray beard and sharp blue eyes. He has written more than 35 books on cryptozoology and is a fixture on such shows as “Unsolved Mysteries” and other programs that examine matters like the existence of UFOs. Unfortunately, he didn’t have much to say about our spider.

“That sounds like something the island residents made up to drum up the tourist trade,” he said dismissively.

We enjoyed ourselves anyway, taking pictures with the huge, moldy-looking Bigfoot statue and peering at supposed fecal samples of the Abominable Snowman. And I was pleased to discover a corner dedicated to “Giant Spiders of the Congo and Cameroon,” which recounted (in text typed out on printer paper) how missionaries reported seeing spiders “half the size of Volkswagens.”

“Other [sightings] mention the Giant Spiders being reported under tents, eating pygmy babies, and running through campsites,” the paper declared.

Good Lord, I thought. These Maine spiders are nothing compared to the African ones. No wonder Coleman had no time for my quest.

We continued on in our trusty Pontiac Vibe, driving slowly up the coast toward Islesboro. Soon after settling into our charming gray-shingled cabin, just outside Lincolnville, we went into town to purchase ferry tickets to Islesboro — about a half-hour ride past other small, forested islands. When I asked the man at the ticket counter, who sported a salt-and-pepper ponytail and a New England Patriots polo shirt, about the up-island spider, his blue eyes widened.

“Oh, it’s real,” he said, stretching out his fingers to show me the size. “But it only lives on the north end of the island — up island. It’s a habitat thing,” he said cryptically, adding, “Ask at Durkee’s General Store. They’ll know.”

Durkee’s alerts you to the fact that you’re in up-island spider territory with an enormous brown plastic-and-fabric model perched on its sign. Wikipedia had told me that residents of Islesboro believe that the heart of the up-island spider population can be found at a church near Durkee’s. The teenage checkout girl hadn’t heard about that, but she directed me to the church and assured me that the spiders are real.

“I think I saw a baby one,” she said, making a circle about two inches in diameter with her hands. “But they can be the size of dinner plates.”

The Free Will Baptist Church (organized 1821, building 1843), a quintessential New England clapboard structure with black shutters and a black steeple, was closed that afternoon, but we could easily walk around the grounds and the graveyard. The idea is that the up-island spider may have first been transported to Islesboro in a coffin; hence the church, where the coffin was placed, as the origin and core of the spider population.

A few crickets chirped and a plane droned overhead while we tramped over grass and a sponge-like moss. Though I kept my eyes on the ground, scanning for brown hairy legs and red eyes, I only came across deer and moose scat, as well as a small, brilliantly red dragonfly resting on a blade of grass. Brian teasingly pointed out webs and their tiny spider residents in the white flowering bushes scattered around the cemetery.

Later, we rushed back to the terminal to make the last ferry out at 4:30. With a few minutes to spare, I stepped inside the keeper’s dwelling of Islesboro’s old lighthouse, Grindle Point Light, just steps from the terminal. The old residence now houses a Sailor’s Museum featuring maritime artifacts and photographs, and Jim, a volunteer, was sitting behind a desk by the door. We got to talking after I signed the guest book. I decided to ask about the spider. Jim, an elderly gent with a shock of white hair, seemed like the type of person who’d give me a straight answer.

“Well, I’ve seen small ones,” he said, making the same size circle with his hands as the checkout girl at Durkee’s. He laughed. “They show up at the most inopportune moments, like crawling on your bedspread.” Eek.

We had a great week in Maine, even if we didn’t find any up-island spiders. We dawdled in the cafes and bookstores of the nearby and almost absurdly picturesque towns of Camden and Belfast. We made lobster rolls, ice cream and the locally brewed Andrew’s English Pale Ale our daily midday meal and tried to burn off some of the calories with woodsy climbs in Camden Hills State Park and walks along the blueberry fields of Beech Hill Preserve. We even went canoeing in Portland’s Casco Bay with dear college friends and pondered moving to the area for good.

Once back in Washington, I e-mailed Jonathan Coddington, curator of arachnids and myriapods at the Smithsonian’s National Museum of Natural History. I sent him a couple of pictures that Islesboro residents had taken of what they took to be the up-island spider, one poised in a sink, one hovering on a log.

“Almost certainly Dolomedes tenebrosus,” Coddington graciously shot back.

Of course, I had to look it up: the Dark Fishing Spider, found all over the Northeast (and the South, for that matter). There was nary a red eye to be seen, and the females, the larger sex, max out at about 31 / 2 inches, including the legs.

Ah, well. It made sense. But, I thought, even if ultimately the up-island spider didn’t turn out to be “real,” searching for them in one of the most beautiful American landscapes was pure pleasure.

Kirk is an editor and writer in Washington.