Lone star ticks push further across Vineyard

Local biologist fears infestation of Vineyard Haven and Oak Bluffs in five years.

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Matthew C. Kramer

Lone star ticks have colonized parts of Chappaquiddick and the Vineyard’s three up-Island towns and are now advancing on the Island’s population centers, biologist Dick Johnson told The Times.

Mr. Johnson is a Vineyard Vision fellow who conducts tick surveys on behalf of the Martha’s Vineyard boards of health. Within half a decade, he said the predatory ticks could be as prevalent and bothersome as mosquitoes in Oak Bluffs and Vineyard Haven.

Unlike deer ticks, lone star ticks don’t transmit Lyme disease, but they can infect people with spotted fever, tularemia, ehrlichiosis, and southern tick-associated rash illness (STARI). Lone star ticks also can also trigger an unusual meat allergy called an alpha-gal allergy. The root of this allergy is not believed to be pathogenic, according to University of Massachusetts Amherst microbiologist Stephen Rich, but from a sugar transmitted during the blood meal process. As National Geographic reported this year, galactose-alpha-1, 3-galactose or alpha gal, a sugar common in meat such as beef, can stimulate some people to work up alpha gal specific antibodies when they ingest meat after a lone star tick bite. The antibodies’ assault on alpha gal causes reactions that can range from nausea, vomiting, and hives to anaphylaxis and severe deterioration requiring ICU level care. The severity of a person’s reaction can be compounded by subsequent bites, National Geographic also reported. The condition is thus far incurable. However, according to Tufts tick researcher Sam Telford, the condition should go away in a few months provided the individual receives no further tick bites.

“But if you keep getting bitten, you will stay allergic,” he wrote in a text message. He added that it remains unclear at what intervals bites need to occur to sustain the allergy.

“So much we don’t know about this condition,” he wrote.

Mr. Telford told The Times in March that female lone star ticks often evidence a white “star” on their backs, but not all lone star ticks have the white spot. “All of them, however, are round and brown,” he said. “And they all move fast.”

Lone star ticks don’t seek hosts just through questing — waiting on foliage for something to pass by — like dog and deer ticks do, Mr. Johnson said. They also chase. An Aquinnah resident told Mr. Johnson that lone star ticks crept out from the woods and across a lawn to attack him while he tinkered with a boat in his yard. Unlike deer ticks, lone star ticks have eyes, and detect carbon dioxide emissions, i.e., human exhales. They use those senses to hone in, Mr. Johnson said. Also unlike deer ticks, lone star ticks can deliver a bite that smarts. Mr. Johnson said the ones he’s experienced felt worse than being bitten by a deer fly. One reason for this, Mr. Rich said, may be because the lone star tick possesses particularly “stout” mouth parts.

Based on his surveys, the Island’s lone star tick epicenters are Cape Pogue and the vicinity of Gay Head Light, Mr. Johnson said. Small birds like towhees and sparrows are believed to have carried lone star ticks to the Island, Mr. Johnson said. He also suspects gulls are transport factors. But on-Island, deer are what mainly feed and distribute the ticks, he said. Turkeys are lone star tick hosts, too, he said and in the midwest the tick is also known as the turkey tick. He added that notwithstanding what they may consume while foraging, there is some debate as to how well turkeys are able to preen and eat the ticks from themselves and moreover what value, if any, turkeys’ ingestion of preened or foraged lone star ticks has against the spread of the ticks on-Island, Mr. Johnson said needs further research.

“Are the turkey’s helping or hurting us?” he asked.

Whatever the case, he noted that like deer, Island turkey populations are robust and increasing. The key to suppressing the Island’s surging lone star tick populations, and the diseases linked to them, is to reduce the Island’s deer herds, Mr. Johnson said. The Island has transformed from a giant expanse of sheep pasture that was inhospitable to deer to a place rich with the woods and thickets that deer thrive in, he said. House lots carved into these woods and thickets create yard-woodland interzones that deer love to browse, he said. It’s these borders where they deposit many of the ticks that find their way to people. Since the Island is riddled with properties hedged with woods, a ready framework exists for lone star tick distribution, he said. Whereas deer ticks tend to lurk in habitats like leaf litter to avoid drying out, lone star ticks can be found on dry pine duff, dune grass, and sand, Mr. Johnson said, and seem resistant to environments that would dessicate deer ticks. Deer ticks, like carpenter ants, contain a glycol that acts like antifreeze in the winter — helping to preserve them, Mr. Johnson said. Since the lone star tick is a migrant from the southeast, he is unsure if it developed such a chemical, he said. If it hasn’t, a low-digit winter might decimate it, he said, but emphasized that this was speculation.

Part of the lone star’s gift for rapid Vineyard expansion may be due to its reproductive power. Engorged female lone star ticks can lay up to 5,000 eggs at a time, Mr. Johnson said. The egg masses look like dollops of minute caviar. The larvae that hatch from them are disease free because they haven’t fed yet, Mr. Johnson said. Nevertheless, they can be an irritant. He’s received reports of birdwatchers with their skin and clothing aswarm with them after passing through vegetation on Chappy. Mr. Johnson said he itched maddeningly after brushing up against a concentration of lone star tick larvae in Aquinnah.

The dog tick and the deer tick have long been on Martha’s Vineyard, let alone the in commonwealth but not the lone star tick.

“Ten years ago they were pretty much unheard of in Massachusetts,” Mr. Rich said.