Ann. Zool. Fennici 44: 225–231 ISSN 0003-455X Helsinki 21 June 2007 © Finnish Zoological and Botanical Publishing Board 2007 Human impact on wolf activity in the Bieszczady Mountains, SE Poland Jörn Theuerkauf 1 , Roman Gula 1 , Bartosz Pirga 1 , Hiroshi Tsunoda 2 , Julia Eggermann 3 , Barbara Brzezowska 4 , Sophie Rouys 5 & Stephan Radler 6 1) Museum and Institute of Zoology, Polish Academy of Sciences, Wilcza 64, PL-00-679 Warsaw, Poland (e-mails: jtheuer@miiz.waw.pl, rgula@miiz.waw.pl, wrzosowe_wzgorze@poczta.onet.pl) 2) Wildlife Conservation Laboratory, Department of Agriculture, Tokyo University of Agriculture and Technology, Saiwai-cho 3-5-8, Fuchu-shi, Tokyo, 183-8509, Japan (e-mail: dayan_and_jitan@ hotmail.com) 3) Faculty of Biology, Ruhr University Bochum, Universitätsstr. 150, D-44801 Bochum, Germany (e-mail: julia.eggermann@web.de) 4) Department of Animal Ecology, Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, PL-30-387 Kraków, Poland (e-mail: bulbulek@wp.pl) 5) Conservation Research New Caledonia, B.P. 2549, 98846 Nouméa, New Caledonia (e-mail: rouys@ifrance.com) 6) University of Applied Forest Sciences Rottenburg, Schadenweilerhof, D-72108 Rottenburg, Germany (e-mail: stephan.radler@fh-rottenburg.de) Received 2 Jan. 2007, revised version received 20 Mar. 2007, accepted 25 Feb. 2007 Theuerkauf, J., Gula, R., Pirga, B., Tsunoda, H., Eggermann, J., Brzezowska, B., Rouys, S. & Radler, S. 2007: Human impact on wolf activity in the Bieszczady Mountains, SE Poland. — Ann. Zool. Fennici 44: 225–231. Human activity is sometimes seen as the reason for nocturnal activity of wolves (Canis lupus). We tested this assumption in the Bieszczady Mountains (southeastern Poland), a region with a human density of 44 inhabitants km –2 , and where wolves were hunted until recently. The radio tracked wolves of three packs moved throughout the day with one major peak around dawn. Wolves avoided the area around main public roads more at night (up to a distance of 1.5 km) than in the day (up to 0.5 km). Wolves avoided a 0.5-km area around secondary public roads and paved forest roads both at night and in the day but did not avoid the surroundings of settlements. As compared with other studies, wolves in this study were the least nocturnal although human density was the highest. We conclude that human activity is unlikely to be the reason for nocturnal activity in wolves. Introduction Activity patterns of wolves (Canis lupus) differ considerably among study areas: wolves were mainly nocturnal in Italy (Ciucci et al. 1997), Spain (Vilà et al. 1995), Croatia (Kusak et al. 2005) and Minnesota (Chavez & Gese 2006), active in the day and at night in Canada (Kolenosky & Johnston 1967) and Alaska (Fancy & Ballard 1995), and had bimodal activity pat- terns in northeastern Poland (Theuerkauf et al. 2003a). Vilà et al. (1995), Ciucci et al. (1997) and Kusak et al. (2005) related the mainly noc- turnal activity patterns of wolves in southern