Fewer frogs died on Maine roads in the spring of 2020, at the onset of the COVID-19 pandemic.
A recent study released by University of Maine graduate student Greg LeClair found that the decrease in traffic caused by lockdowns and the early stages of the pandemic had a significant impact on frog mortality rates.
Adult frogs, salamanders and other amphibians migrate in the early spring. They often cross roadways, and end up getting run over by vehicles.
LeClair gathered data on amphibian migration from March 15 to May 15 of 2020 to understand how reduced travel impacted frog populations, along with other amphibians. The data found that 50 percent fewer frogs were hit by vehicles in 2020 than in the three previous years.
The data collection is part of an annual project to understand amphibian behavior called the Maine Big Night: Amphibian Migration Monitoring program. Volunteers across the state gather information from March to May. Since 2018, 426 volunteers have taken part in this project.
The study did not identify a significant decrease in the number of salamanders that were killed by vehicles. LeClair noted that this could be because of the conditions that salamanders tend to favor.
According to his research, frog migration tends to increase during warm, rainy spring nights. However, salamanders tend to travel less frequently during periods of rain, LeClair said.
Data from the Maine Department of Transportation also shows that there were a fewer number of animal deaths throughout the state due to the pandemic than during typical years.
LeClair hopes that the research will help people to understand ways to help the amphibian population — such as avoiding traveling during rainy spring nights — as well as help to raise awareness about the impact of human behavior on ecosystems.