Impact of Anatolian Motorway on Large Mammals: Quantifying the Permeability and Impact Zones
(Oral and Poster)
Ali Onur Sayar
, Deniz Özüt
, Anil Soyumert
, Hasan Emir
, İrfan Kandemir
SEE PEER REVIEW
Roads are one of the major structures that cause habitat fragmentation all over the world. Motorways and highways especially create a greater disturbance due to their size and extent, not only by increasing the fragmentation but also by resulting in edge effect. Large mammals, due to their need for extensive areas for resources, have large home-ranges, which are more easily fragmented by roads acting as barriers. Motorways and highways may further act as total barriers for certain species, dividing their populations.
Turkey is home, still, to a great diversity of large mammals. However, being a developing country, an extensive amount of infrastructure projects have been under way in an increasing fashion during the last two decades. Roads have been built in excessive amounts, serving as the main infrastructural elements to connect new and enlarged settlements and resource extraction sites such as mines and dams. A total of 17,000 kms of highways were built in Turkey during the last decade. Unfortunately, the effects of roads on wildlife have not been assessed. This study is the first one evaluating the road's effects on wildlife in Turkey.
In order to evaluate the effects of roads on wildlife, a 100 km. segment of the Anatolian motorway, connecting Ankara and İstanbul, is monitored for two years, using 200+ camera traps located at every underpass. The surrounding forest areas were monitored using additional 55 camera traps utilizing systematic grids at 1,5 x 1,5 kms.
A total of 2068 red fox, 1926 golden jackal, 934 wolf, 692 wild boar, 168 brown bear, 32 lynx, 10 red deer and 3 roe deer passing events recorded (filtered by hour). Out of three types of underpasses - culvert, multi-use underpass, viaduct - herbivores used only the viaducts. The heights of underpasses - but not the length or width - significantly affect the preference of all carnivores except red fox. An additional effect of the road on the use of large mammals at varying distances from the road is determined: the use of roadside areas were lower than average use in the 0-500 m. zone while it peaked in 500-1500 m. zone, and undulating around average use at 1500-5000 m. zone on both sides of the road. Such a pattern, caused by the effect of road was also determined in several other studies.
INTRO: Roads are one of the major causes of habitat fragmentation. Therefore, in developing countries where an extensive amount of infrastructure are under construction, conservationists are worried about the impact of motorway and highway on wildlife. This study, done in Turkey, uses more than 200 camera traps to monitor big mammals movement in underpasses and surroundings. The study highlight how different species use a different type of underpasses depending on their dimensions and the distance from the roads. Roads are one of the major causes of habitat fragmentation. Therefore, in developing countries where an extensive amount of infrastructure are under construction, conservationists are worried about the impact of motorway and highway on wildlife. This study, done in Turkey, uses more than 200 camera traps to monitor big mammals movement in underpasses and surroundings. The study highlight how different species use a different type of underpasses depending on their dimensions and the distance from the roads.
MERITS: Habitat fragmentation is a key problem for the conservation of many species especially big mammals. Therefore, this study can give precious information in building passages when a road cut territories. The big amount of data collected gives strength to the study and the chosen research variables are easily to communicate to local governments and to technical professionals.
CRITIQUE: Authors affirmed that this is the first study evaluating the road's effects on wildlife. Maybe I misunderstood what they meant because there is already a rich literature about road's effects on wildlife. In the abstract, authors should highlight what is the innovation of this study compared to the previous ones.
DISCUSSION: The implications of this study are evident in the conservation of big mammals facing road's effect on wildlife. This kind of data is easy to be communicated to stakeholders and can mitigate great consequences on wild populations due to habitat fragmentation. Collecting data with camera traps, maybe authors could record other information and not just the species that use the underpasses. For example, they can gather from the photos information about sex, age, the dimension of the herds, numbers of cubs, etc. Useful information to understand if the road's effect changes considering different individuals and groups.