…from the ESRI Map Book, Volume 24…
“With nearly 10,000 kilometers (6,214 miles) of motorway, 25,500 kilometers (15,845 miles) of trunk roads, and 1,600 kilometers (994 miles) of high-speed train lines in Basse-Normandie, transport networks dividing up natural habitats can have two main effects on animal and plant species. One, they reduce the size of the habitat such that populations of species with large home ranges can no longer survive in them. The other effect is the isolation of the remaining habitat patches, such that species have little chance of moving from one to the other.
“In this situation, the species concerned are threatened with local or regional extinction. It is through these processes that habitat fragmentation by transport networks and the resulting secondary phenomena have become the most serious threats to biological diversity on the planetary scale.
“As part of the French national strategy for biodiversity, and in response to the alarming report on the assessment of the A84 motorway concerning collisions with wildlife, the Environment and Geomatics department of the CETE Normandie Centre set up this study of ecological networks in order to propose development plans in favor of the species concerned and to improve the safety of road users.
“Courtesy of CETE Normandie Centre.”