Traffic kills millions of animals
In Finland, millions of mammals, birds and amphibians die in traffic every year. However, the four-legged pedestrians are nowadays taken into account when new road networks are being planned.
Badger’s life ended by the side of the road. Photo: Milla Niemi.
There are no exact figures of how many animals die every year in traffic. The most recent mapping can be found from a report, published in 2002. According to it, traffic kills one million mammals, one million amphibians, and three to four million birds annually in Finland.
“The data behind these figures is not very extensive, so the numbers are pure estimates,” says PhD candidate Milla Niemi from the University of Helsinki.
Niemi has done her Master’s degree in Forest Zoology in the Department of Forest Ecology. At the moment she studies road kills. In a recent project Niemi and her colleagues studied how a stretch of land under a bridge, crossing a rivers, offers a safe route for animals. These dry stretches of land have been built for the purpose of making the bridge maintenance easier, but they also function as underpass for animals.
This is only one example of different underpasses, overpasses and crossings that help reduce the amount of road kills. According to Niemi, the best option is to build roads in tunnels so that the so-called roof of the tunnel is left in natural condition.
Some animals learn to use crossings, some use them by chance
In Finland, animal crossings are quite a new thing. However, in new road projects, animals are taken into account. For example along the recently built motorway from Helsinki to Turku, there is a green bridge going over the four lanes.
There are also some underpasses that are big enough for elks, and culverts for smaller mammals and amphibians along the major roads in Finland. The usage of these crossings happens mostly at random.
“If we look at a young mammal looking for new habitat, it uses the crossing if it happens to be on its way. However, elk, for example, that roams long distances, learns to use certain routes and certain crossings and teaches these routes to its fawns as well,” Niemi explains.
Judging by the amount of tiny spoors, the dry stretch of land under a bridge has been used as a safe crossing by many animals. Photo: Milla Niemi.
Habitat fragmentation causes problems
Even though the number of roadkills seems very high, traffic is not a substantial threat to any endangered species in Finland at the moment. Otter is endangered in many countries in Central Europe, and it is a very typical roadkill as well.
“It is important to have eye on otter in Finland as well and observe its habitats and take them into consideration in road planning even though the Finnish otter population has even grown slightly,” Niemi says.
However, the road kills are only the most visible problem with road networks. The roads prevent animals from moving and expanding their habitat. When a certain population lives in an enclosed area, the genetic diversity decreases.
“If a road divides the population into two or more fragments, the members of which don’t reproduce and exchange genes, it can be a threat to the of the population. There is a link between the decrease of genetic diversity and growth in risk of extinction,” Niemi explains.
Next Niemi’s research will concentrate in collisions with elks. She will compare statistics and look for disparities in collisions in different parts of Finland.
“We also aim at finding out whether predicting and mapping the sites where collisions are most likely to occur is possible.”
Sentimentality leads to cruelty
What to do then when an animal is hit by a car? Niemi advises to first make sure that the animal really is dead.
“Typically an animal smaller than elk suffers from so severe injuries that there is no point in trying to rescue it,” she says and encourages people to use common sense: “Taking a severely injured wild animal across Finland to Korkeasaari Zoo, for example, is a clear case of animal cruelty.”
“By law injured animals have to be put down. Nowadays people are overly sentimental when it comes to death, and that may lead to more cruelty than killing,” lecturer of Forest Zoology Petri Niemi from the University of Helsinki points out.
The best way to put down an injured animal is a quick blow on the neck with some heavy object at hand. Then the animal should be moved from the driveway so other motorists won’t hit it. Authorities don’t have to be notified about the incident unless there have been injuries that have to be dealt with insurance company, for example. If the animal is a pet, the owners should be notified, if there is contact information on the collar.
Scavengers eat the smaller carcasses from the side of the road and road contractors collect some of them. Local hunters have contracts with the police so when there is a collision with larger carnivore or elk, they get rid of the carcass.
“The Museum of Natura History collects samples from rarer species, such as otters and bats, and the museum’s Ringing Centre is interested in receiving the rings of dead ringed birds,” Niemi advices and continues:
“Not all people stop after hitting an animal, because they fear that they have to do something to the animal, and get their hands dirty. When it comes to pets, people may think that they have to compensate for a pedigree animal, which is not true. If a cat or a dog runs loose in the middle of traffic, driver is not liable.”
The Finnish Museum of Natural History
Elisa Lautala works as web editor for University of Helsinki's Faculty of Science. Elisa likes all kinds of cultural events, good books, warm weather, and aqua-jogging.