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Article (refereed)Dowding (Singleton et al., 1999;Stenseth et al., 2003).72 Consequently, a range of methods is employed to reduce rodent density and 73 associated damage. This is most commonly done in developed countries using 74 anticoagulant rodenticides, vitamin K antagonists that prevent the synthesis of 75 functional prothombrin and related blood-clotting factors. Extensive use of first-76 generation anticoagulant rodenticides (FGARs) during the 1950s, however, led to the 77 evolution of genetic resistance in brown rats (Rattus norvegicus), with widespread 78 cross-resistance to other compounds (Cowan et al., 1995;Thijssen, 1995). As a 79 result, more potent second-generation anticoagulant rodenticides (SGARs) were 80 developed which have a greater affinity to binding sites, resulting in greater 81 accumulation, persistence and toxicity (Parmar et al., 1987; Huckle and Warburton, 82 1986). 83Given their mode of action, both FGARs and SGARs are potentially harmful to all 84 vertebrates, and so users are expected to adopt measures that limit direct exposure 85 to non-target species. However, the degree to which these preventive measures are 86 adhered to, particularly by non-professionals, is unknown. For example, in Britain 87 some products are readily available to householders who may be less aware of the 88 risks of non-target poisoning and/or less likely to follow manufacturer's guidelines.89 Non-target species may also be deliberately poisoned (Barnett et al., 2006). 90Most studies investigating indirect exposure of non-target species to 91 anticoagulant rodenticides have focussed on the consumption of poisoned rodents by 92 predatory birds and mammals (Newton et al

Traffic collisions can be a major source of mortality in wild populations, and animals may be expected to exhibit behavioral mechanisms that reduce the risk associated with crossing roads. Animals living in urban areas in particular have to negotiate very dense road networks, often with high levels of traffic flow. We examined traffic-related mortality of red foxes (Vulpes vulpes) in the city of Bristol, UK, and the extent to which roads affected fox activity by comparing real and randomly generated patterns of movement. There were significant seasonal differences in the number of traffic-related fox deaths for different age and sex classes; peaks were associated with periods when individuals were likely to be moving through unfamiliar terrain and would have had to cross major roads. Mortality rates per unit road length increased with road magnitude. The number of roads crossed by foxes and the rate at which roads were crossed per hour of activity increased after midnight when traffic flow was lower. Adults and juveniles crossed 17% and 30% fewer roads, respectively, than expected from randomly generated movement. This highly mobile species appeared to reduce the mortality risk of minor category roads by changing its activity patterns, but it remained vulnerable to the effects of larger roads with higher traffic flows during periods associated with extraterritorial movements.