Earth 365: A warm winter's impact on Pennsylvania's tick population
PITTSBURGH (KDKA) - As we approach Earth Day this weekend, CBS News and KDKA-TV continue to highlight our commitment to covering stories about the Earth all year long.
Earlier this week in our "Earth 365" series, we explored the reasons behind the unusually warm winter we had and the impact that's having on local crops and farming.
But that's not the only fallout from our warm winter. It's also impacting Pennsylvania's tick population.
"We have blacklegged ticks in all 67 counties in the commonwealth. And we have a lot of those pathogens that the blacklegged tick can transmit in every county in the commonwealth as well, especially Lyme Disease and the causative agent of anaplasmosis", said Christian Boyer, a tick specialist with the Pennsylvania Department of Environmental Protection.
And those pathogen-passing ticks can be more active in the winter if the conditions are right.
"Usually most ticks, specifically the main species of tick that we have in Pennsylvania, which is the blacklegged tick, can only be active if the temperature is above 40 degrees. Which means that when we have really weak winters, that tick can be active even outside of the normal time frame. So, the time frame when people are at risk of tick bites increases," said Emily Stuckhoff, a Vector-Borne Disease program specialist with PSU Extension.
While dealing with the established dog ticks and blacklegged ticks more of the time, a warmer winter like the one we just finished wouldn't necessarily mean we would see more of these ticks.
But some issues occur when you see warmer winters over time. Since 1970, Pittsburgh has seen its winters warming, on average, faster than any other season.
This has led to an average of ten fewer nights each winter with temperatures below freezing.
During that same period, we've seen an average of eight fewer cold snaps, too.
As our winter climate is changing, so are some habitats. And with changing habitats, come new inhabitants.
"When you have milder winters, you can see those ticks expand their ranges further and further north. So that's something that we're even seeing in the northeast and in the upper mid-west, where there are some species that have historically been constrained to the southern United States," said Stuckhoff.
And it's not just one species making Pennsylvania their home.
"The ones that have been increasing are the new, invasive ticks. Such as the Asian longhorned tick, which showed up in Pennsylvania in 2019. The lone star tick, which is another invasive tick in Pennsylvania, has been mostly a southern tick. And I think it's just that their survivability is increasing with the warmer temperatures. I think their eggs are viable throughout the winter and they're becoming more viable as the warmer temperatures increase. And we have another tick, the gulf coast tick, that was just discovered in 2020 and established populations in the Philadelphia area in 2021. And I think that can be attributed to warming weather conditions in the right habitat. Once they find that, they can flourish," said Boyer.
And controlling tick populations is not as easy as it may sound.
Stuckhoff said, "There is not a 'one size fits all' widespread control option available."
Pesticides are available, but pesticides also kill beneficial insects. So, they should be used very sparingly. There are things you can do to protect yourself, though.
Ticks thrive in tall grasses and bushy areas. Keeping those low in areas where people frequent is important, as is checking yourself and your pets for ticks when you come inside after being in areas like that.
All things to keep in mind as our area becomes more hospitable to ticks.
"Especially these ticks that are expanding north and expanding their range. And we'll continue to see that in Pennsylvania," said Boyer.
It's also important to note that different species of ticks carry different pathogens, so Lyme Disease isn't our only tick related issue.
That said, we are just now coming into the nymphal blacklegged tick season, and nymph life stage is the one that is mostly connected to the transmission of Lyme Disease and other tickborne pathogens to people because of their small size.
Our "Earth 365" series continues Friday.
"On The Dot" host David Schechter checks in with one of America's top climate scientists to see if we're making any progress on controlling global warming.
Plus, KDKA First Alert meteorologist Falicia Woody travels to Erie to see how climate change is impacting Lake Erie and, in turn, our weather and the fishing industry along the lake.