Researchers from Madrid University found that 70% of collisions occurred on just 7.7% of the roads in the area they studied. According to the authors: "Large animals such red deer, roe deer and wild boar are forest species, but their territory includes other habitats. Often they forage outside forest, especially when there are few people around. This then brings them into contact with roads, with disastrous consequences."
The study found that collision black spots occur where animals find it easier to cross roads in the absence of human habitation. Fences or large, steep embankments deter animals from crossing roads and funnel animals to easy crossing points. At these points planners should install over- or underpasses for animals, the researchers say.
The need to consider the impact of roads on wildlife is emphasised in a second paper in the same issue of the Journal of Applied Ecology.
The Eurasian lynx is extremely rare in Germany and attempts at reintroduction are being made. Ecologists have found that conservationists need to reduce road mortality if such schemes are to be effective. Researchers from the UFZ Centre for Environmental Research found that the high density of roads in Germany means that many lynx are killed moving around the landscape.
According to the researchers: "The dense transport system results in high mortality. This gives clear management directives for dealing with reintroductions of lynx in Germany."