Resumen
The negative influence of extension of transportation system over fauna populations mainly consists in destroying their natural habitats, causing higher animal death rates (road accidents), fragmentation of sites and hindering migration as well as isolating animal populations. From the point of view of ecologists, fragmentation of animal life caused by transportation ways is a much bigger problem than collisions in which individual animals die. Big animals must migrate and contact other groups, otherwise they will not survive. That is why relevant technical solutions need to be applied, for example animal crossings of relevant overall dimensions. The paper characterizes the problem of preservation of wildlife animals in connection with extension of transportation road systems. The constantly evolving transportation infrastructure in Europe, especially in its Midwestern part, on one hand connects, making it easier for people to travel and ship goods, but on the other hand it irreversibly divides and leaves its painful impress on virgin natural areas (fragmentation of the environment). It enumerates possible types of animal crossings together with their characteristics. Some examples of underpasses, overpasses and crossing on the road surface are also presented. It also presents specificity and phases of designing engineering structures of this type, as well as the most common design errors and their influence over the use of such structures by animals. The conclusion mentions complexity of the problem of animal crossing construction, which can be of use to designers and constructors of this type of engineering structures.