Pioneering study predicts true impact of roadkill on wildlife

August 16, 2018, University of Reading
Credit: Charles Sharp, 2015, South American tapir (Tapirus terrestris), accessed on 16th August 2018 here, CC Attribution-Share Alike 4.0 international

A new tool that predicts which animal species are most at risk of dying on roads, and in which areas, could aid efforts to preserve global biodiversity.

Research by the University of Reading and University of Lavras has allowed estimates to be made for the first time of the number of likely to become roadkill every year, and the characteristics that put some more at risk than others.

The method was used for the first time in Brazil, and estimated more than 10 million animals die on its roads each year. Given Brazil is thought to be the most biodiverse country in the world, the findings are significant to the planet as a whole. The scientists argue they should be taken into account when considering future infrastructure plans.

Manuela Gonzalez-Suarez, conservation biology lecturer at the University of Reading and lead author, said: "Roadkill is known to have an impact on biodiversity, but little work has been done to quantify this, and identify which animals are most at risk. We have shown for the first time that roadkill risk can be predicted based on species' characteristics or traits, such as their size, behaviour, and ecological preferences."

The research, published in the journal Global Ecology and Biogeography, used existing roadkill data to predict future risk.

It calculated that more than 8 million birds and 2 million mammals become roadkill in Brazil every year. The researchers found animals that eat a more diverse diet and use a range of habitats are most at risk, likely because they encounter roads more often and decide to cross them. Road mortality rates were higher for bigger birds with ground foraging behaviour, and for medium-sized, scavenging mammals in Brazil.

Based on the identified relationships, the authors found that birds and mammals occupying the Amazon have characteristics that make them particularly susceptible to road impacts. There are currently relatively few roads in the Amazon, but many animals in coastal areas were found to be at greater risk due to the greater number of roads there.

In Brazil, economic and social growth has made investment in infrastructure a priority. Proposed plans include a 20 percent increase in roads covering regions of exceptional biological diversity and global ecological importance like the Cerrado and the Amazon.

The researchers are now looking to apply their method to other regions to measure the impact of roadkill around the world.

Flavio Zanchetta Ferreira, who compiled the data for the study at the University of Lavras in Brazil, said: "In Brazil, several groups have conducted assessments but we are still missing data for many areas and species.

"New roads are always going to be needed as countries develop their infrastructures, but it is hugely important that research like this is factored into decisions on their location to minimise environmental impact."

Clara Grilo, a co-author from the University of Lavras, said: "Roadkill can reduce population abundance, limit dispersal, decrease genetic diversity, and eventually lead to local extinction. We need to understand these risks to protect biodiversity and threatened species."

Explore further: Researchers may be underestimating roadkill numbers

More information: Manuela González-Suárez et al. Spatial and species-level predictions of road mortality risk using trait data, Global Ecology and Biogeography (2018). DOI: 10.1111/geb.12769

Related Stories

Researchers may be underestimating roadkill numbers

May 14, 2018

A new study in the Journal of Urban Ecology, published by Oxford University Press, indicates that the number of wild animals killed by motor vehicles may be much higher than is generally reported or understood.

How to save animals by reducing roadkill

April 4, 2017

Hundreds of millions of animals are killed every year by road traffic. It's a sad statistic that Jochen Jaeger, associate professor of geography in Concordia's Faculty of Arts and Science, and his international colleagues ...

Pheasant roadkill peaks in autumn and late winter

October 3, 2017

Chickens' motives for crossing the road are often questioned - but pheasants should probably avoid it altogether, new research suggests. Researchers from the universities of Exeter and Cardiff compared roadkill figures from ...

Roadkill studies on the rise

September 13, 2010

(PhysOrg.com) -- Roadkill is the stuff of jokes and sometimes supper. But wild animals hit by vehicles are a serious concern of some ecologists, including UC Davis researcher Fraser Shilling, who just completed the first ...

Roadkill hot spots identified in California

April 17, 2015

An interactive map shows how California's state highway system is strewn with roadkill "hot spots," which are identified in a newly released report by the Road Ecology Center at the University of California, Davis. The data ...

Recommended for you

Scientists engineer new CRISPR platform for DNA targeting

January 23, 2019

A team that includes the scientist who first harnessed the revolutionary CRISPR-Cas9 and other systems for genome editing of eukaryotic organisms, including animals and plants, has engineered another CRISPR system, called ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.