The use of military bunkers by the European badger and red fox in Western Europe

Abstract

Intensification of agriculture and land consolidation policy induced the removal of most natural features from farmland, reducingthe habitat of many wild species. AbandonedWWII bunkers, unaffected by land consolidation, are a potential shelter for wildlifeand could be used as burrows by carnivores such as European badgers and red foxes.We explored 182 abandoned bunkers in a farmland area in eastern France in summer 2016. Bunkers were located in crops,forests, or groves. Over a three-month period, signs of presence, the number and type of burrows inside the bunkers and in theirimmediate vicinity were noted. Environmental variables were obtained using GIS, and binomial models were created to revealparameters influencing bunker use by badgers and foxes. The degree of bunkers burrowing was used as a co-variable. Twentyonegroves without bunkers were also studied in order to estimate the added value of bunkers in groves.Badger and fox tracks were found on 34% of the sites, and burrows on 24% of them with similar rates for badgers and foxes.Animals used partially buried bunkers more than underground or overground bunkers. The sizes of annual crops and urban areasaround the bunker were positively correlated with bunker use. The presence of a bunker in groves was positively correlated withthe presence of burrows in groves.As bunkers were widely used by badgers and foxes, they may improve conservation in intensive farming landscapes. Werecommend the management of these ruins to facilitate the sustainable installation of a variety of species.