ORIGINAL PAPER Habitat use and spatial patterns of wild boar Sus scrofa (L.): agricultural fields and edges Henrik Thurfjell & John P. Ball & Per-Arne Åhlén & Peter Kornacher & Holger Dettki & Kjell Sjöberg Received: 12 October 2008 / Revised: 16 March 2009 / Accepted: 26 March 2009 / Published online: 21 April 2009 # Springer-Verlag 2009 Abstract Rapidly increasing populations of wild boar in Sweden and Europe cause much damage to crops, and there is a critical need for more knowledge about their habitat utilization, especially of agricultural fields. In our study, we first assess the spatial pattern of damage in relation to the edges of agricultural fields. Next, with the aid of global positioning system collars, we studied the pattern of movement of wild boar on agricultural fields. Finally, in order to understand the role of agricultural fields, we studied how habitat selection may vary throughout the year. We found edge effects on damage patterns in agricultural fields. During winter and spring, we found wild boar not only to follow edges, but also to move along narrow landscape elements within agricultural fields. In our habitat analysis, we found strong avoidance of exposed agricultural fields throughout the year, but significantly less when crops are ripe. Keywords GIS . Edge effect . Damage . Sweden Introduction Wild boar (Sus scrofa, L.) were hunted to extinction in Sweden in the seventeenth century, and reintroduced and hunted to extinction again in the 1940s. In the 1970s, wild boar escaped from enclosures where they were held for hunting and meat production. The population has grown rapidly in the southern and central parts of Sweden and wild boar are once again considered a part of the Swedish fauna (Truvé and Lemel 2003). Currently, farmers are suffering crop damage, and hunters feed the wild boar to increase their numbers and provide hunting opportunities. This has lead to a conflict of interests—a common problem in many areas of Europe (e.g., Wenum et al. 2003; Calenge et al. 2004; Geisser and Reyer 2004; Herrero et al. 2006). From a management perspective, it is important to evaluate and estimate the activity patterns of wild boar (Pettersson 2007). In this study, we have both mapped the damage on agricultural fields to investigate their spatial pattern, and we have followed 17 large sows equipped with global position- ing system (GPS) collars. Our aims were to determine the spatial patterns of damage to agricultural fields, to evaluate the spatial patterns of wild boar movements on the agricultural fields, and to analyze the habitat selection of wild boar in order to examine how this (especially their use of agricultural fields) may change over time. Damage and forest edges Previous studies have suggested that damage caused by wild boar is not located randomly with respect to forest edges (e.g., Briedermann 1990; Geisser 1998; Lemel 1999). If fields are located close to a forest edge, damage levels are often very high (Lemel 1999) and a relationship among the fragmentation of the landscape, the length of the forest-field edge and damage intensity have been suggested (Drozd 1988). In the scientific literature, there are few quantitative studies on how wild boar forages with respect to edges (e.g., Geisser 1998; Meriggi and Sacchi 2001) although it has been suggested that wild boar feeds close to edges in Eur J Wildl Res (2009) 55:517–523 DOI 10.1007/s10344-009-0268-1 Communicated by E. Hadjisterkotis H. Thurfjell (*) : J. P. Ball : P.-A. Åhlén : H. Dettki : K. Sjöberg Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, 901 83 Umeå, Sweden e-mail: henrik.thurfjell@vfm.slu.se P. Kornacher Makoa Farm, P.O. Box 203, Moshi, Tanzania e-mail: pkornacher@web.de