Introduction: the scale of the problem
As road infrastructures proliferate, traffic volumes and speeds rise, and ungulate densities also increase throughout Europe (Gill, 1990; Apollonio et al., 2010), so the frequency of road traffic accidents involving wildlife also escalates throughout Europe.
In 1982 some 10 000 road accidents were recorded in Sweden due to collisions with moose, red deer and roe deer; by 1993 that number had risen to 55 000, with mortality of roe deer alone in excess of 50 000 (Groot Bruinderink and Hazebroek, 1996). Statistics presented by Groot Bruinderink and Hazebroek showed this to be a general trend throughout Europe, and suggested that, at that time, vehicle–ungulate collisions in Europe as whole may have been of the order of 500 000. Estimates offered by Apollonio et al. (2010) indicate that, at least in those countries where estimates are attempted, numbers had risen substantially by 2005 (Table 8.1). Formal records are only maintained in a small proportion of countries, whereas in many others comparable data are not available. It is therefore not possible to offer an accurate estimate for the total number of collisions occurring in Europe as a whole, although we may note that totals recorded in the table (for fewer than half the countries of Europe) already approximate to 400 000, with the full toll of ungulates killed annually on European roads likely to be closer to 1 million.