Ticks prove resilient to extreme temperatures
by Will Ferguson, Washington State University
June 01, 2023
PULLMAN, Wash. — Tick season is here, along with the increased danger of Lyme disease, and it turns out the tiny arachnids are even tougher than scientists previously thought.
A recent study in Ecological Monographs shows blacklegged ticks (Ixodes scapularis) are actually really good at surviving extreme cold and heat in nature. Previous lab research suggests that even short periods of especially warm or cold conditions should easily kill ticks, but the Washington State University-led analysis reveals this is only the case for larval ticks in the environment. Instead, nymph and adult ticks weather the hot and cold times with little impact, dying when they apparently run out of energy. The findings could ultimately provide valuable insights into the spread of Lyme disease and other vector-borne pathogens.
“We thought we would see some evidence that if there was like a very dry period, all the ticks might be at a greater risk of dying,” said Jesse Brunner, lead author of the study and an associate professor of biological sciences at WSU. “However, just the larvae were impacted by heat and dry conditions. Cold weather had even less of an impact. Somehow, they hunker down and survive great.”
Blacklegged ticks are notorious carriers of pathogens responsible for various diseases, including Lyme disease, which is the most common vector-borne illness in North America. Over the years, these ticks have expanded their range significantly across the Eastern United States and Midwest, challenging previous assumptions about their preferred habitats. While one of the culprits is likely climate change, scientists have yet to clearly establish why ticks are abundant in some areas while rare in others.
Read the Ecological Monographs paper: https://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/ecm.1572