COVID-19 Lockdowns Altered Mammal Movements Worldwide in 2020

Reduced traffic and human mobility during the 2020 COVID-19 lockdown restrictions rapidly altered some mammals' movement behaviors, according to a new study. The findings illustrate how human activities constrain animal movement and how they react when those activities cease, which provides valuable insight into future conservation strategies designed to improve human-wildlife coexistence. During the initial global outbreak of COVID-19 in 2020, governments worldwide introduced lockdown measures to curb the spread of the virus, resulting in a drastic reduction in human mobility and vehicular traffic. This "anthropause," as it's come to be known, has provided a unique opportunity to quantify the effects of human activity on wildlife behaviors. Human roadways and the need for animals to cross them is important to the conservation of many species. Not only do they reduce habitat and limit the movement and population dispersal for many species, but vehicle collisions can also be a notable source of animal mortality. Despite this, relatively little is known about the impact of roads on animal behavior across species and at global scales. Leveraging the natural experiment afforded by COVID-19 lockdowns, Marlee Tucker and colleagues compiled GPS tracking data from 76 studies – a dataset that encompassed 2300 individual mammals, representing 43 species from around the world – and evaluated how they changed their behaviors during the initial 2020 lockdown period (February 1 – April 28^, 2020) compared with the same period in 2019. Although individual movement and road avoidance behavior responses to lockdowns varied across species and regions globally, Tucker et al. revealed several consistent effects. According to the findings, in locations where COVID-19 lockdown policies were stricter, animals traveled on average 73% farther during the lockdown period than the previous year, suggesting that most animals in these locations were exploring more of the landscape when vehicle movement was reduced. Additionally, the analysis revealed that length of short-distance mammal movements in populated human areas was reduced, and individuals traveled 36% closer to roadways during lockdowns. Tucker et al. suggest that this is because animals were less fearful of the road traffic or human presence in these regions and exhibited shorter fleeing distances as a result. "Tucker et al. provided a comprehensive answer about the ability of some animals to make use of human-inhabited areas and even expand their habitats when human activity declines," write Colleen Cassady St. Clair and Sage Raymond in a related Perspective. "Their results highlight the environmental impact of vehicle activity, which is discussed less often publicly than the effects of emissions, permanent road infrastructure, and habitat loss."