Roadkill is a tragic, seemingly inevitable part of driving. Roads are almost impassable barriers for many animals, and especially problematic during active mating seasons. The LIFE LINES project in the Alentejo region of Portugal is reshaping roadsides to protect wildlife at risk.
Owls, genets, frogs and salamanders – there are many different species with varying behaviours that suffer from the existence of roads that split their habitats. Roads affect populations, contribute to genetic isolation of species, and fragment breeding and feeding areas. Other so-called grey infrastructure – power lines and railways – also pose challenges to the movement of fauna.
In Alentejo, LIFE LINES is addressing the risks to wildlife whose habitats are near such infrastructure. The region is an apt choice because it contains the main land transport links between Lisbon and Madrid, with many roads and power lines.
Diverse species, many solutions
The common genet (Genetta genetta), a small carnivorous mammal, is widespread in the region. This made it a useful focus for the LIFE LINES team to understand how hunting carnivore mammals traverse roads. Biologists from the University of Évora fitted GPS trackers to individuals to learn their patterns of movement. Based on data gathered, they could map the characteristics of the areas around the roads and determine the best mitigation actions.
This January, the project team finished building various roadside barriers and guiding infrastructure.
Owls and other night-time predators can quickly be disoriented by headlights and collide with passing vehicles. After analysing roadkill hotspots, the team set up netting to prevent owls and other flying vertebrates crossing the road too low and being hit by vehicles. Most at risk are slow-moving amphibians, especially when the ponds and streams they need to breed in lie on the other side of a road. Extended water passageways under the road have been put in place to connect toads, newts and other amphibians with their breeding grounds.
The project received invaluable help from local volunteers and municipal staff to put these protective barriers up and add road signs explaining the changes.
“People keep asking about the frog signs”
António Mira has been doing a lot of media work recently. The LIFE LINES project coordinator described what happened after new road signs showing frogs and owls were put up. “People started phoning the authorities to ask why the road signs were there, and what it was all about,” he said. “The public is really starting to understand why this work is important, and how it is financed. We’re focused on explaining everything.”
Visibility continues to grow. LIFE LINES has recently started a weekly slot on a local radio station where a different aspect of the work is presented. And thanks to the level of interest, the project was also presented on national TV.
“If you told me a year and a half ago we would have achieved this, I would not have believed it,” said Mr Mira.
How data can drive change
At the beginning of 2018, the Portuguese assembly passed 3 draft resolutions around monitoring wildlife deaths, studying ecosystem impacts and adopting preventative measures. They’re an indication that the government recognises the negative impact of grey infrastructure on biodiversity.
Independently, LIFE LINES has been building a dataset covering the abundance and distribution of species and recordings of roadkills. It will work as a common platform for infrastructure operators, including the national roads company Infraestruturas de Portugal, conservation bodies and universities.
“My aim is that this data will be sharable with as many people as possible”, Mr Mira explained. Currently there are some restrictions because it is used in postgraduate research. Permission is needed from some bodies holding the data before sharing it with the public.
“We know the best way to get people on board is to meet face to face, so we’ll be traveling to 12 different infrastructure bodies to discuss with them the value of this data”, he added.
How to balance biodiverse verges and fire risks
Alongside the data mapping and infrastructure improvements conducted by the team, biologists from the University of Évora have been collecting, storing and sowing seed mixtures. In order to create a stable population of native plants – herbaceous plants, bushes and trees which are often rare in traditional beds – large quantities are needed.
The seed beds set up by the project will provide shelter, cover and support for different sizes and species of animals.
Local schoolchildren have been pitching in to help – clearing cane plants in the area and replacing them with native plants and bushes such as ash, arbutus and cork.
But in the wake of devastating wildfires in 2017, there is a tendency to strip roadside verges right back to minimise fire risk. While justified, this comes with strong consequences for biodiversity.
To combat this, the project is presenting the government with a new proposal on how to manage fire risk without compromising biodiversity. “If properly managed, roadside verges can act as small corridors to allow fauna the movement it needs,” says Mr Mira.