Storaas, T. (2014). To feed or not to feed? Evidence of the intended and unintended effects of feeding wild ungulates.Journal of Wildlife Management, 78(8) Large ungulates are keystone species in many ecosystems and are a highly valued natural 47 resource for social, cultural, and economic reasons (Gordon et al. 2004). Many populations have grown over recent decades, causing environmental and socio-economic 49 impacts on wider communities and conservation concerns, as well as density-dependent 50 changes in performance (Côté et al. 2004, Putman et al. 2011. Consequently, conflicts 51 arise between stakeholders who benefit economically from high ungulate numbers (e.g., 52hunters, outfitters, tourism operators) and those faced with the costs of their presence 53(e.g., land managers, conservationists, transport users and operators; Austin et al. 2010). 54Manipulating forage availability through the provision of additional food could 60Wildlife can be fed by humans in many different ways, intentionally (e.g., at 61 feeding stations) and unintentionally (e.g., unprotected agricultural crops and rubbish 62 dumps; Oro et al. 2013, Sorensen et al. 2014. In this review, we focus on the effects of 63 intentional feeding of ungulates, specifically considering supplementary feeding (often 64 called winter feeding) and diversionary, or intercept, feeding used to attract animals away 65 from vulnerable vegetation, livestock, or major traffic arteries (defined fully in 66 Supplemental Material). However, many of the issues raised also apply across a broad 67 range of unintentional but predictable anthropogenic food subsidies (Oro et al. 2013). 68Earlier reviews of the consequences of feeding large herbivores, published a decade or 77 METHODS 78We reviewed articles in the peer-reviewed and, to a lesser extent, grey literature that our search terms resulted in 232 articles. 86We identified 5 major management goals of supplementary and diversionary 87 feeding and considered the intended effects of feeding that would allow these goals to be 88 achieved (Table 1). We also identified commonly perceived unintended or secondary 89 consequences of feeding ( Table S1). 152Among adult females, an effect of feeding is complicated by the strong impact of 153 reproductive status on autumn mass (Cook et al. 2013 and higher neonatal growth rates (Jacobsen et al. 1981, Smith et al. 1997). 160The reproductive rate (number of offspring per adult female in summer or 161 autumn) of supplementally fed herbivores increased in 5/7 studies ( were used (Gundersen et al. 2004, Sahlsten et al. 2010 feeding site users and non-users (van Beest et al. 2010b). 282Of 16 controlled studies, 6 showed diversionary feeding to be effective in 283 reducing damage in the targeted areas, whereas 4 showed a significantly increased 284 impact, opposing the management goal ( we found no studies that formally addressed this ( 379In studies addressing the increased probability of browsing or grazing impacts in 380 response to feeding (4/4 studies; Table 2 and Supplem...

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Declines in populations of capercaillie (Tetrao urogallus) and black grouse (Lyrurus tetrix) have been reported from both Central Europe and the continuous boreal forests of Fennoscandia. While intensified land-use is assumed to be the underlying cause of these declines, the mechanisms are not yet understood. Predation is the proximate cause of mortality of eggs, chicks and adults throughout capercaillie and black grouse ranges, but the link between predation and habitat and/or climate change remains unclear. To investigate temporal trends in reproductive output of woodland grouse, we collated previously published and unpublished data of reproduction in capercaillie and black grouse throughout their ranges from 1930 to 2012. We show that, overall, reproductive success has decreased and stabilized at low levels in most regions whilst capercaillie reproductive output in Scotland is still declining. With today's net reproduction, capercaillie and black grouse adult survival is too low to compensate for reproduction declines. Consequently, populations are expected to further decline unless reproductive performances improve. We put our findings in the context of changes in land use, climate and generalist predator numbers. By critically reviewing how these factors limit reproductive success in capercaillie and black grouse, we hope to shed light on the underlying mechanisms causing the decline. Our results imply that measures should be undertaken to reduce mortality of capercaillie and black grouse chicks and eggs. We suggest that future studies should aim to better understand which predators limit capercaillie and black grouse populations and how predation rates are mediated by continuously changing habitat and climate.

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We studied the simultaneous activity patterns of a breeding wolf (Canis lupus) pair and five adult moose (Alces alces) cows from April through November 2004 in a wolf territory in south-eastern Norway. All study animals were GPS collared, and we used a total of 8,297 fixes to analyze their temporal activity patterns. We 1) describe the daily activity rhythm of the two species and how this varied seasonally through the study period, and 2) investigate the association in activity patterns between the two species. Wolf activity peaked at dawn. The distance moved per time unit and the linearity of the movement was higher in wolves than in moose, but both species showed a decrease in these variables in June, coinciding with the denning and calving seasons. With the exception of the summer months when the activity of wolves and moose was limited by the raising of offspring, we found no correlation between the temporal activity of the two species.1 Author for correspondence: Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biology, University of Oslo, PO Box 1066 Blindern, N-0316 Oslo, Norway; e-mail: ane.eriksen@bio.uio.no; phone: (+47) 45269840 2 Hence, we did not find support for the hypothesis that the wolves and moose in Scandinavia have adjusted to each other's activity patterns. We discuss the results in light of the relative density of the two species and the intensive human harvest of moose, and hypothesize that synchronicity of predator-prey activity patterns may be ratio-dependent.Keywords: Activity pattern, Alces alces, Canis lupus, GPS-collar, moose, predation risk, predator avoidance, wolf.Continuous arms races are believed to be ongoing in predator-prey systems (Dawkins & Krebs 1979; Matter & Mannan 2005), resulting in a variety of predator-and anti-predator adaptations (Stephens & Peterson 1984). As one such adaptation, prey may adjust their activity pattern in response to that of their predator, and vice versa. Predators may increase their access to prey by being active in periods when prey is active (Jenny & Zuberbühler 2005). Conversely, prey may avoid their predators by reducing activity when predators are active (Nelson & Vance 1979; Overdorff 1988) or in circumstances in which predators find it easy to locate prey (Caro 2005). Prey, in particular females with young, may also avoid their predators in space by shifting their habitat use in response to predators (Main 1987; Festa-Bianchet 1988; Decaestecker et al. 2002; Caro 2005).The moose, Alces alces, is an important Holarctic prey species for wolves, Canis lupus (Peterson & Ciucci 2003), including within the boreal forests of south-central Scandinavia (Sand et al. 2008). Wolves and moose may both adjust their activity patterns to a number of factors, and when correlations between wolf and moose activity are found, it is a challenge to separate between those resulting from the same external factors acting on both species, and actual adjustments of one of the species to the activity pattern of the other. Without bei...

We analyzed how the application of scent‐marking, forest clearing, and supplemental feeding correlated with the number of moose (Alces alces)–train collisions along the most vulnerable railroad stretch in Norway. Data on 1,045 collisions has been compiled for 18 years since 1985, and remedial actions have occurred during various periods since 1990. We used sections of the rail line where remedies had never been applied as control sections to estimate the expected number of collisions per year and per km. In this way, we took into account the yearly variation in the number of accidents by using the difference between the actual number of accidents and the expected number of accidents as our response variable. We compared the difference between periods when remedies were applied to periods without any remedy. We found a general 46% decrease in the number of accidents during years with a remedy compared to what would have been expected the same years without any remedy. Forest clearing and supplemental feeding seem to be reliable ways of reducing the number of collisions. Scent was only applied for short distances in a few years, and the beneficial effects we observed were questionable. We conclude that mitigative efforts may substantially reduce accidental mortality in moose populations if applied for long distances. We discuss the economics of game‐vehicle collisions by performing a simple calculation to visualize the need for a bio‐economic approach to the problem.

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We used hunting dogs and man to simulate the searching for nests and broods of forest grouse, i.e. capercaillie Tetrao urogallus and black grouse Tetrao tetrix, by mammalian predators. Our aim was to find out if and how forest fragmentation affects the searching efficiency of predators. In total, we found 73 capercaillie and 35 black grouse nests and 20 young capercaillie broods. We calculated that a mammalian predator will detect a capercaillie nest if closer than 1.6 m (95% C.I.: 0.7 ‐ 2.2), a black grouse nest if closer than 1.1 m (95% C.I.: 0.8 ‐ 1.6), and a capercaillie brood if closer than 39 m (95% C.I.: 17 ‐ 89). Nests were distributed in all habitat types, whereas broods were restricted to specific brood habitats. Due to this and the difference in the detection radius between nests and broods, we estimated that the predator gain of searching for broods in brood habitat is about 80 times higher than the gain of searching for nests which are situated in all habitat types in our study area. As young broods concentrate in highly restricted habitats, the predator gain of searching for broods increases exponentially with the loss of brood habitat, whereas it decreases linearly with increasing nest predation. We discuss this mechanism as a possible process explaining the observed decline in capercaillie populations in fragmented forests and consider its implications for grouse management.