The season of the dog tick

Dog tick numbers high after a dry spring, with lone star nymphs on the rise after heavy rain.

A dog tick — Wiki Commons

Every spring on the Martha’s Vineyard, Islanders seem to say: “It’s the worst tick season there’s ever been.” But are the ticks actually worse this year? 

Patrick Roden-Reynolds, of the MV Tick Program, couldn’t definitively say if there are truly more ticks in 2023 compared to other years, but he has seen a dramatic increase of dog ticks in his surveys this past month.

“I’ve probably collected double the amount of dog ticks this year compared to last year at this time. The dog ticks have been particularly abundant,” said Roden-Reynolds. “People are saying it’s the worst tick season they’ve ever seen, and unfortunately we’re just barely getting into it.”

Though the dog ticks are “abundant,” they are the largest, most easily noticeable, and least likely to successfully transmit serious diseases. American dog ticks — also known as wood ticks, scientific name Dermacentor variabilis — carry and can transmit the diseases tularemia and rocky mountain spotted fever. They are typically brown or mottled brown in color with a yellow “collar.”  Dog ticks can transmit disease but out of the three tick species found on the island, they seem to be “bad” vectors, as the tick expert put it, of transmitting disease. “You still want to avoid bites,” he said. 

During tick season, from April to September, Roden-Reynolds performs twice monthly tick surveys at six different trail locations around the island. “It gives me an idea of what’s out and what’s active,” says Roden-Reynolds. The collected sample is how experts like Roden-Reynolds can definitively say that the dog tick numbers have, indeed, been up. “In the past month I was collecting mostly dog ticks on my sample. I’ll find 50 dog ticks, 6 lone stars, and 6 deer ticks, for example,” he said.  

Roden Reynolds had a theory on this season’s high numbers of dog ticks. He suspected that dog ticks, being more robust and larger, are more able to tolerate dry conditions than other smaller types of ticks. With only a few days of rain this spring, and most ticks preferring a wetter climate, he guessed the dog ticks were simply able to better tolerate the dry conditions and that’s part of the reason for their abundant numbers.

In addition to dog ticks, he also reported from his recent surveys an increase in numbers of lone-star nymphs, the type of tick that carries alpha-gal syndrome. “One day I found 75 lone star nymphs, double the amount I’ve picked up in any other survey this year,” Roden-Reynolds said. The climate may play a role in the most recent spike. “The rain we had last weekend might’ve kickstarted some activity, because it’s been a pretty dry spring, which in the end helps with the tick situation,” he said. 

Ticks are very sensitized to climate and moisture, and most thrive in humid and damp conditions, particularly smaller ticks. Larger, more “robust” ticks, as Roden-Reynolds put it, like mature dog ticks, are able to tolerate dryer conditions.  

Dog ticks in particular are found in green, grassy vegetation, fields, and meadows. Hikers and dog walkers interested in minimizing tick exposure might try to stay in the middle of the trail, away from overhanging vegetation and tall grass, or to opt for walking on paved roads and sidewalks instead of in the woods. 

Still, anywhere on the island is a possible tick habitat, especially for the pioneering dog tick. “They are a bit more mobile and can withstand the dryer conditions, so they can travel and end up in odd places you wouldn’t expect for a tick,” Roden-Reynolds said. 

As part of his work at the MV Tick Program, Roden-Reynolds surveys six different trails across the island. The surveys are performed using a tick flag, which he described as the gold standard for collecting questing ticks in the scientific research community. It’s a white piece of cloth attached to a broom handle that is dragged through the woods over leaf litter and vegetation. Ticks posed in “questing” position latch on to the flag, thinking it’s an animal host. Every few steps, Roden-Reynolds checks the flag for ticks and uses a lint roller to collect ticks off the flag. “After the survey that gives me an easy way to count and organize them by sex and life stage,” he said. 

Then they go into a freezer, are tested for pathogens, or are sent to research collaborators, like Professor of Infectious Diseases Sam Telford at Tufts University. There they conduct research on lyme disease, babesiosis, and other tick-borne illnesses. 

The MV Tick Program offers a residential survey program as well, where Roden-Reynolds makes house calls to evaluate backyards and residential properties for tick habitat. “I’ll come and do the tick flagging and dragging in your yard for anyone who is interested and wants to have me come over,” he said. “Flagging the yard gives me a general idea of how many ticks I’m finding in the yard, whether it’s 1 tick, 5 ticks, or 50 ticks. It’s pretty common to come up with 5 ticks, that’s not too much of a concern here on the Vineyard. But if I’m picking up 40 or 50 ticks, that puts people more at risk,” he said. Roden-Reynolds then speaks with homeowners to discuss recommendations for what they can do to reduce the number of ticks. 

The number one thing all homeowners can do to discourage ticks from habitating in their yard is raking up and removing leaf litter.  “All ticks are tied to leaf litter, so anywhere you can rake it up and really clean up the perimeter of the yard will help,” Roden-Reynolds said. Leaf litter offers ticks their preferred damp environment. Deer ticks especially are very sensitive to moisture and like to hide in the moisture of leaf litter. 

The other tactic Roden-Reynolds recommends is installing a deer fence.  “Keep the deer off your property, because they’re the ones bringing the ticks close to the home,” he said. “The hosts are bringing the ticks around to different parts of the island. Lone stars and dog ticks can crawl, but they’re not gonna go that far, 30 feet at most.”

MV Tick Program offers home surveys May 15th through July 31st.  “We are really trying to sample during the peak tick season,” says Roden-Reynolds. The survey takes about an hour, and is free, although donations to the Tick Program are encouraged. 

“I don’t want the thought of having to pay, turn people away from what I’m doing,” says Roden-Reynolds.  

The MV Tick program was established in 2011. The program recently received a public health grant, but before then, the program ran entirely on donations. 

“There’s a lot of people in this community that care about keeping this program alive,” said Roden-Reynolds. 


  1. I remember Jim Athearn telling me one time that the ground doesn’t freeze properly during a mild winter, you’re going to see a lot of ticks come summer.

  2. Jenna- Great article with a ton of good information. I highly recommend the yard surveys if you are concerned about ticks around your house. Patrick can also provide information about permethrin treated clothing which provide the best protection from ticks when you are walking trails or just out and about.

Comments are closed.