Are several small wildlife crossing structures better than a single large? Arguments from the perspective of large wildlife conservation

Crossing structures for large wildlife are increasingly being constructed at major roads and railways in many countries current guidelines mitigation linear infrastructures tend to advocate crossing sited movement corridors the target species. The concept of has, however, been challenged pinching animal movements into bottlenecks entails risks. In this paper, I address SLOSS dilemma road ecology, i.e. discussion whether a Single Large Or Several Small along barrier would produce most benefit wildlife, using case Sweden. point out risks, ecological as well practical, with investing one structure list number situations where it may be more beneficial distribute conservation efforts landscape by constructing several smaller structures; example, when knowledge is insufficient, interactions expected significant, changes over time or future human development cannot controlled. argue that such often what infrastructure planning faces default strategy, therefore, should distribute, rather than concentrate passage opportunities transport infrastructures. suggest distributing convey risk diversification strategy could facilitate mitigation. What choose however depend on, inter alia, composition ecology on relationships amongst A single selected likely can serve proportion animals long-term functionality guaranteed. New research needed support trade-offs between size structures. Cost-effectiveness analyses currently rare need further explored. Camera trapping video surveillance provide analyse details concerning, any individual biases according sex, age, status grouping antagonism species individuals. Wildlife needs better questions posed railway regarding importance specific routes distances.