Evidence of usage of Estonia`s first ecoduct by mammals

E263 Tallinn-Tartu-Võru-Luhamaa road is one of the most important national routes in Estonia, connecting capital Tallinn to university town Tartu and South Estonian region. The road separates Estonia`s mainland into two halfs and cuts several important habitats of wild mammals, including large carnivores like gray wolf, brown bear and Eurasian lynx and ungulates like moose, wild boar and roe deer.

Estonia`s first wildlife overpass was built in 2013 on a well-known moose migration corridor during road construction of Aruvalla-Kose road segment on E263. The average annual daily traffic volume on Aruvalla-Kose section was 11 000 vehicles per day in 2015 which makes road-crossing very difficult or even impossible for many species. Road section was upgraded from a regular two-line road to a four-lane partly fenced first class road and several wildlife passages (four small/medium mammal tunnels, three amphibian tunnels, bridge underpass and an ecoduct) were constructed. Three more overpasses and three same-level crossings (fence-breaks) for large mammals are being planned to the next road section. While planning and building such massive and expensive mitigation measures it is important to determine, which species and how often use the passages.

Estonian Road Administration retained Estonian Naturalists` Society to conduct effectiveness monitoring of the wildlife passages on Aruvalla-Kose road section from February 2015 to December 2016. Two infrared-triggered trail cameras Uovision UM565-SMS (GPRS) 12MP were placed on the ecoduct. Additionally, 4 m wide track-pad was checked and raked smooth weekly.

Data presented in this study was received by analysing trail camera photos from period 1 April 2015 –31 March 2016. Cases of two or more individuals crossing together were counted as multiple crossings. Additional data received by checking track-pads was not included.

The first year of monitoring has shown that the most active overpass users are domestic cats (35,8% of total 1006 camera-registered crossings) and red fox (25,9%), followed by wild boar (11,5%) and roe deer (9,6%), domestic dogs (4,8%), humans (4,7%), raccoon dogs (3,6%), gray wolf and European hare (both 0,9%). Also odd crossings by European pine marten and European hedgehog were registered. In 1,9% of the cases the animal species remained unidentified. Further monitoring is necessary to determine if number of wildlife crossings increases in time and if the target species moose starts using the ecoduct.

camera monitoring, mammals, ecoduct