Wolf Diet Research Articles

Estimating biomass of berries consumed by gray wolves

ABSTRACTGray wolves (Canis lupus) consume berries and other wild fruits seasonally when available or abundant. However, a method to convert percent frequency of occurrence or percent volume of berries in wolf scats to percent biomass has not yet been developed. We used estimates of the average number of blueberry (Vaccinium spp.) seeds in 10 individual wolf scats collected in and adjacent to Voyageurs National Park, Minnesota, USA, along with published values of the number of seeds per blueberry and blueberry masses to estimate that a wolf scat containing only berries equated to an average of 0.468 kg of berries consumed. We recommend using this berry conversion factor (0.468 kg/scat) to convert the percent frequency of occurrence or percent volume of berries and other wild fruits to percent biomass when estimating wolf diets from scats. © 2017 The Wildlife Society.

Reconstruction of the extinct Ezo wolf's diet

On Hokkaido, Japan, the Ezo wolf Canis lupus hattai, an apex predator, became extinct at the end of the 19th century owing to human activities. Top predators often have an important role in their ecosystems, yet we have no scientific information on the feeding habits of the Ezo wolf. We performed carbon and nitrogen stable isotope analysis and radiocarbon dating of specimens of the wolf (n = 7) and its prey species and estimated the components of the wolves’ diet using an isotope mixing model. Radiocarbon dating suggested that most of the wolves examined came from different populations or generations. The mean stable isotope ratios of the wolves were −19.5 ‰ (±1.9 ‰ sd) for δ13C and 8.7 ‰ (±2.6 ‰ sd) for δ15N. The discrimination-corrected isotopic ratios of five of the seven wolves were almost the same as those of Sika deer at the same sites. In contrast, those of two wolves had clearly higher isotopic values than those of deer, suggesting that these wolves depended partly on marine prey such as salmon and marine mammals. Thus, Ezo wolves had similar ecological roles to Canadian grey wolves, and were a second subspecies shown to have fed on a marine diet, in addition to the ‘coastal wolves’ of British Columbia.

Weekly Summer Diet of Gray Wolves (Canis lupus) in Northeastern Minnesota

Abstract Wolves (Canis lupus) are opportunistic predators and will capitalize on available abundant food sources. However, wolf diet has primarily been examined at monthly, seasonal, or annual scales, which can obscure short-term responses to available food. We examined weekly wolf diet from late June to early October by collecting scats from a single wolf pack in northeastern Minnesota. During our 15 wk study, nonungulate food types constituted 58% of diet biomass. Deer (Odocoileus virginianus) fawns were a major food item until mid-July after which berries (primarily Vaccinium and Rubus spp.) composed 56–83% of weekly diet biomass until mid-August. After mid-August, snowshoe hares (Lepus americanus) and adult deer were the primary prey. Weekly diet diversity approximately doubled from June to October as wolves began using several food types in similar proportions as the summer transitioned into fall. Recreational hunting of black bears (Ursus americanus) contributed to weekly wolf diet in the fall as wo...

What does the wild boar mean to the wolf?

Generalist predators are expected to shape their diets according to the local availability of prey species. In turn, the extent of consumption of a prey would be influenced by the number of alternative prey species. We have tested this prediction by considering the wild boar and the grey wolf: two widespread species whose distribution ranges overlap largely in Southern Europe, e.g. in Italy. We have reviewed 16 studies from a total of 21 study areas, to assess whether the absolute frequency of occurrence of wild boar in the wolf diet was influenced by (i) occurrence of the other ungulate species in diet and (ii) the number of available ungulate species. Wild boar turned out to be the main prey of the wolf (49% occurrence, on average), followed by roe deer (24%) and livestock (18%). Occurrence of wild boar in the wolf diet decreased with increasing usage of roe deer, livestock, and to a lower extent, chamois and red deer. The number of prey species did not influence the occurrence of wild boar in the wolf diet. The wild boar is a gregarious, noisy and often locally abundant ungulate, thus easily detectable, to a predator. In turn, the extent of predation on this ungulate may not be influenced so much by the availability of other potential prey. Heavy artificial reductions of wild boar numbers, e.g. through numerical control, may concentrate predation by wolves on alternative prey (e.g. roe deer) and/or livestock, thus increasing conflicts with human activities.

Quantifying prey selection of Northern and Southern European wolves (Canis lupus)

Wolf (Canis lupus) diet is determined by several ecological factors which can differ with latitude and human impact on the environment. Here we aim to compare Northern and Southern Europe with respect to wolf feeding habits. Scats were collected and analysed for nine years in South-central Scandinavia and four years in Tuscany, Italy, where prey density, predator-prey size relation and habitat heterogeneity, were compared in different ecological perspectives. Consumption followed prey density in Scandinavia but not in Tuscany and the main prey species, moose and wild boar respectively, were more seasonally age diversified in Scandinavia than in Tuscany. Most likely, the risk of injury was an important factor in prey age selection, especially in Tuscany. Diet composition in Scandinavia showed a negligible variance while in Tuscany, temporal and spatial variation were clearly recognised. The underlying mechanism is most likely related to the limited ecological diversity of landscape in Scandinavia contrasted with the higher variability of South European landscapes resulting in higher variation in prey abundance and consequently prey choice.

Exploitation of marine resources by wolves in southwestern Alaska

Predation by large carnivores is a dominant factor shaping wildlife communities and an understanding of local foraging strategies of predators is central to the management of wildlife populations. Information on local foraging strategies is particularly important where carnivores might exploit alternate resources that could influence predator–prey interactions, carnivore population dynamics, and a variety of interactions at lower trophic levels. We used carbon (δ13C) and nitrogen (δ15N) values in serially sampled wolf ( Canis lupus ) vibrissae to quantify relative resource use and dietary variation among wolves ( n = 115) from 4 areas in southwestern Alaska that differed in the availability of terrestrial and marine resources. Mean vibrissae isotope values varied by ~8‰ for δ13C and ~12‰ for δ15N and showed high levels of spatial, seasonal, and individual variation. While results showed that ungulates were the principal prey for wolves in all 4 areas, wolves also exploited a variety of alternate marine resources that represented an important component of wolf diets in some areas. Estimated dietary contributions from marine resources ranged from 28% to 56% among areas and use of these resources varied both spatially and seasonally. Dietary variation and use of marine resources increased from northeast to southwest along the Alaska Peninsula with increasing access to coastal areas and decreasing ungulate abundance. Seasonal shifts in resource use were also evident with dietary variation being highest during summer and fall when wolves consumed more alternate resources than during winter. Our findings suggest that use of marine resources and local variation in foraging strategies of wolves might, through a variety of pathways, have broad implications for the management of wolf–ungulate communities in southwestern Alaska.

Intestinal parasites of gray wolves (Canis lupus) in northern and western Canada

Gray wolves (Canis lupus L., 1758) are mobile opportunistic predators that can be infected by a wide range of parasites, with many acquired via predator–prey relationships. Historically, many of these parasites were identified only to genus or family, but genetic tools now enable identification of parasite fauna to species and beyond. We examined 191 intestines from wolves harvested for other purposes from regions in the Northwest Territories, British Columbia, Saskatchewan, and Manitoba. Adult helminths were collected from intestinal contents for morphological and molecular identification, and for a subset of wolves, fecal samples were also analyzed to detect helminth eggs and protozoan (oo)cysts. Using both detection methods, we found that 83% of 191 intestines contained one or more parasite species, including cestodes (Taenia spp., Echinococcus spp., and Diphyllobothrium sp.), nematodes (Uncinaria stenocephala Railliet, 1884, Trichuris spp., Physaloptera spp., and Toxascaris leonina (von Linstow, 1902)), a trematode (Alaria sp.), and protozoa (Sarcocystis spp., Giardia sp., and Cryptosporidium spp.). Molecular characterization identified one species of Diphyllobothrium (Diphyllobothrium latum (L., 1758) Cobbold, 1858), three species of Taenia (Taenia krabbei Moniez, 1879, Taenia hydatigena Pallas, 1766, and Taenia multiceps Leske, 1786), and two Giardia duodenalis (Davaine) Deschiens, 1921 assemblages (B and C). These results demonstrate the diverse diet of wolves and illustrate the possibility of parasite spillover among wildlife, domestic animals, and people.

Alternative prey use affects helminth parasite infections in grey wolves.

Predators affect prey populations not only through direct predation, but also by acting as definitive hosts for their parasites and completing parasite life cycles. Understanding the affects of parasitism on prey population dynamics requires knowing how their predators' parasite community is affected by diet and prey availability. Ungulates, such as moose (Alces americanus) and white-tailed deer (Odocoileus virginianus), are often important prey for wolves (Canis lupus), but wolves also consume a variety of alternative prey, including beaver (Castor canadensis) and snowshoe hare (Lepus americanus). The use of alternative prey, which may host different or fewer parasites than ungulates, could potentially reduce overall abundance of ungulate parasites within the ecosystem, benefiting both wolves and ungulate hosts. We examined parasites in wolf carcasses from eastern Manitoba and estimated wolf diet using stable isotope analysis. Taeniidae cestodes were present in most wolves (75%), reflecting a diet primarily comprised of ungulates, but nematodes were unexpectedly rare. Cestode abundance was negatively related to the wolf's δ(13) C value, indicating diet affects parasite abundance. Wolves that consumed a higher proportion of beaver and caribou (Rangifer tarandus), estimated using Bayesian mixing models, had lower cestode abundance, suggesting the use of these alternative prey can reduce parasite loads. Long-term consumption of beavers may lower the abundance of adult parasites in wolves, eventually lowering parasite density in the region and ultimately benefiting ungulates that serve as intermediate hosts. Thus, alternative prey can affect both predator-prey and host-parasite interactions and potentially affect food web dynamics.

Food habits of the world's grey wolves

Abstract Grey wolves Canis lupus have been studied extensively, but there has been no detailed review of the species’ feeding ecology, despite growing debate about how to conserve wolf populations while limiting their impacts on wild or domestic ungulates. Here, we assess the extent to which the grey wolf diet varies among and within North America, Europe, and Asia. We derived dietary data from searches of published literature. We grouped studies based on their bioregional location. We compared grey wolf diet among locations using non‐metric multidimensional scaling and analysis of similarity. We assessed whether increased human impacts are associated with decreased grey wolf dietary diversity. Finally, using studies from southern Europe, we assessed whether the importance of wild ungulates in grey wolf diet has increased over time, coincident with a decline in domestic species in grey wolf diet over time. We compiled dietary data from 177 studies incorporating 94607 scat and stomach samples. Grey wolf diet was dominated by large (240–650 kg) and medium‐sized (23–130 kg) wild ungulates, but variation in the percentages of wild ungulates consumed, along with variation in the percentages of domestic and smaller prey species consumed, contributed to the dietary differences found among and within continents. We found no evidence that grey wolf dietary diversity varies globally, although the results from southern Europe suggest that grey wolves may switch their diets away from domestic species if more wild ungulates are available. The diversity of prey consumed by grey wolves shows that the species is capable of surviving dramatic anthropogenic upheaval. However, there is an urgent need to increase our understanding of grey wolf foraging ecology in human‐dominated landscapes, in order to determine whether restoration of depleted prey populations, coupled with effective damage‐prevention measures, will reduce human‐wolf conflicts.

Why do wolves eat livestock?: Factors influencing wolf diet in northern Italy

Thanks to protection by law and increasing habitat restoration, wolves (Canis lupus) are currently re-colonizing Europe from the surviving populations of Russia, the Balkan countries, Spain and Italy, raising the need to update conservation strategies. A major conservation issue is to restore connections and gene flow among fragmented populations, thus contrasting the deleterious consequences of isolation. Wolves in Italy are expanding from the Apennines towards the Alps, crossing the Ligurian Mountains (northern Italy) and establishing connections with the Dinaric populations. Wolf expansion is threatened by poaching and incidental killings, mainly due to livestock depredations and conflicts with shepherds, which could limit the establishment of stable populations. Aiming to find out the factors affecting the use of livestock by wolves, in this study we determined the composition of wolf diet in Liguria. We examined 1457 scats collected from 2008 to 2013. Individual scats were genotyped using a non-invasive genetic procedure, and their content was determined using microscopical analyses. Wolves in Liguria consumed mainly wild ungulates (64.4%; in particular wild boar Sus scrofa and roe deer Capreolus capreolus) and, to a lesser extent, livestock (26.3%; in particular goats Capra hircus). We modeled the consumption of livestock using environmental features, wild ungulate community diversity, husbandry characteristics and wolf social organization (stable packs or dispersing individuals). Wolf diet varied according to years and seasons with an overall decrease of livestock and an increase of wild ungulate consumption, but also between packs and dispersing individuals with greater livestock consumption for the latter. The presence of stable packs, instead of dispersing wolves, the adoption of prevention measures on pastures, roe deer abundance, and the percentage of deciduous woods, reduced predation on livestock. Thus, we suggest promoting wild ungulate expansion, the use of prevention tools in pastures, and supporting wolf pack establishment, avoiding lethal control and poaching, to mitigate conflicts between wolf conservation and husbandry.

Comparison of DNA and hair-based approaches to dietary analysis of free-ranging wolves (Canis lupus)

Dietary habits of free-ranging animals are essential for understanding their ecology, conservation and management. Carnivore diet is most frequently estimated using morphological analysis of prey remains found in scats. However, genetic methods may identify prey in scats when parts are too small to identify by morphological methods. We developed an easy and accurate molecular approach to assess occurrence of prey species in the diet of free-ranging wolves (Canis lupus) and compared the results to analyses of prey hair in the same scat samples collected from northeastern Alberta, Canada. Species-specific mitochondrial DNA primers detected 1.34 times more prey occurrences from scats, and more readily differentiated similar ungulate species such as woodland caribou (Rangifer tarandus caribou) and deer (Odocoileus sp.) than morphological methods. These findings suggest that molecular analysis of prey in carnivore scat are objective, reproducible and, can help promote effective conservation and management of carnivore species at risk of conflict with humans.

Carbon and nitrogen discrimination factors of wolves and accuracy of diet inferences using stable isotope analysis

Dietary inferences using stable isotope analysis rely on comparing stable carbon and nitrogen isotope content of consumer to prey tissues by modeling discrimination between these tissues. Diet–tissue discrimination factors applied in these models for wild populations must be obtained from controlled feeding studies where consumer diets are known. Species-specific discrimination factors are lacking for wolves (Canis lupus), and most researchers assessing the diet of free-ranging wolves have used discrimination factors derived from red foxes (Vulpes vulpes) fed a commercial pellet diet. We calculated diet–tissue discrimination factors for various tissues from captive wolves fed a controlled diet of horse (Equus caballus) meat and also assessed the feasibility of seasonal delineation of diet through the partitioning of metabolically inactive tissues such as guard hairs and whiskers. Stable carbon isotopic discrimination in wolves was highest in whiskers (4.31‰), followed by guard hair (4.25‰), and lowest in serum (2.21‰) and red blood cells (2.16‰). Stable nitrogen isotopic discrimination was highest in serum (4.54‰), guard hair (3.09‰), and whiskers (3.05‰), and lowest in red blood cells (2.99‰). Using these values, we demonstrated the sensitivity of estimated wolf diet proportions to choice of discrimination factors. We also documented a decrease in growth rate of hair and whiskers from summer through autumn, which cautions estimating temporally explicit diet of mammals based on stable isotope analysis of discrete sections of hair and whiskers. We conclude that species-specific discrimination estimates should be used in dietary assessments based on stable isotope analyses to limit inaccuracies in diet interpretation of wild populations. © 2015 The Wildlife Society.

Indirect effects of changes in environmental and agricultural policies on the diet of wolves

Policies have the potential to affect human–wildlife coexistence. However, despite consequences being evident beforehand or emerging soon after their implementation, potential conflicts between policies and biodiversity conservation are not always easy to predict. Wolves feeding on anthropogenic food sources (AFS) usually fall into conflict with humans, mainly due to predation on livestock. But the availability of AFS can be influenced by different policies leading to diet shifts, which could trigger new conflicts or exacerbate existing ones. Here, we show a long-term shift in the diet of wolves in northwestern Iberia over the last three decades and discuss its potential connection to changes in sanitary, environmental, and socioeconomic policies. Wolves persisted for a long time due to the activity of humans with AFS accounting for >94 % of their diet. Our results suggest a connection between a diet shift in wolves and changes in policies, from a broad diet including more feedlot (pigs, chickens) and medium-sized (goats and dogs) species, mainly in the form of carrion, to a more narrow diet based primarily on large domestic ungulates (cattle and horses). We discuss the potential implications of the observed shift in the diet of wolves on human–wolf conflicts. We also call attention on the pressing need to integrate policies into biodiversity conservation to anticipate future conservation and management dilemmas.

EU Sanitary Regulation on Livestock Disposal: Implications for the Diet of Wolves.

Sanitary and environmental regulations may have indirect effects on the wildlife and ecosystem services beyond their regulatory scope. To illustrate such effects, this paper examines how EU sanitary measures, in conjunction with additional regulations and socio-economic changes, have caused wolf diet to shift in Galicia, northwestern Spain. Prior to the bovine spongiform encephalopathy (BSE) crisis in Europe in 2000, livestock carcasses used to be left on the field and were eaten by scavengers and carnivores. As a result of the BSE crisis, sanitary regulations regarding the disposal of livestock carcasses were introduced. These regulations affected the populations of avian scavengers. We hypothesize that wolf ecology has also been affected by the aforementioned regulations. We analysed wolf diet for the period 2003-2006 and compared the results with those of a previously published study (1974-1978). We found a shift in wolf feeding habits following the implementation of these EU regulations. A decrease in carrion consumption was registered, and wolves increased their feeding on the rising population of wild ungulates, especially on roe deer, and on wild pony. Future regulations should assess their potential indirect effects in the early stages of drafting to allow for the design of proper mitigation measures.

Wolf diet in an agricultural landscape of north-eastern Turkey

AbstractIn this study, we investigated wolf feeding ecology in Kars province, north-eastern Turkey, by analysing 72 scat samples collected in spring 2013. Ongoing camera trap surveys suggest that large wild ungulates are exceptionally rare in the region. On the contrary, livestock is abundant. Accordingly, scats analysis revealed that livestock constituted most of the biomass intake for wolves, although small mammals were the most frequent prey items. Wild ungulates were occasional prey, and although wolves make use of the main village garbage dump as a food source, garbage remains were scarce in scat samples. Wolf dependence on anthropogenic resources, primarily livestock, generates human-wildlife conflicts in the study area. Uncontrolled carcass disposal seems to boost this wolf behaviour. Synanthropy enhances the probability of wolf-human encounters and thus increases the risk of direct persecution, vehicle collisions, and hybridisation with dogs. When livestock is not available, small mammals are an important alternative prey for wolves. This may increase interspecific competition, particularly with lynx, which is also lacking natural prey in the area. Our preliminary results contribute to wolf ecology and conservation in the Anatolian-Caucasian range, where further studies are urgently needed to generate baseline data.

Wolves adapt territory size, not pack size to local habitat quality.

1. Although local variation in territorial predator density is often correlated with habitat quality, the causal mechanism underlying this frequently observed association is poorly understood and could stem from facultative adjustment in either group size or territory size. 2. To test between these alternative hypotheses, we used a novel statistical framework to construct a winter population-level utilization distribution for wolves (Canis lupus) in northern Ontario, which we then linked to a suite of environmental variables to determine factors influencing wolf space use. Next, we compared habitat quality metrics emerging from this analysis as well as an independent measure of prey abundance, with pack size and territory size to investigate which hypothesis was most supported by the data. 3. We show that wolf space use patterns were concentrated near deciduous, mixed deciduous/coniferous and disturbed forest stands favoured by moose (Alces alces), the predominant prey species in the diet of wolves in northern Ontario, and in proximity to linear corridors, including shorelines and road networks remaining from commercial forestry activities. 4. We then demonstrate that landscape metrics of wolf habitat quality - projected wolf use, probability of moose occupancy and proportion of preferred land cover classes - were inversely related to territory size but unrelated to pack size. 5. These results suggest that wolves in boreal ecosystems alter territory size, but not pack size, in response to local variation in habitat quality. This could be an adaptive strategy to balance trade-offs between territorial defence costs and energetic gains due to resource acquisition. That pack size was not responsive to habitat quality suggests that variation in group size is influenced by other factors such as intraspecific competition between wolf packs.

Experimentally derived δ¹³C and δ¹⁵N discrimination factors for gray wolves and the impact of prior information in Bayesian mixing models.

Stable isotope analysis of diet has become a common tool in conservation research. However, the multiple sources of uncertainty inherent in this analysis framework involve consequences that have not been thoroughly addressed. Uncertainty arises from the choice of trophic discrimination factors, and for Bayesian stable isotope mixing models (SIMMs), the specification of prior information; the combined effect of these aspects has not been explicitly tested. We used a captive feeding study of gray wolves (Canis lupus) to determine the first experimentally-derived trophic discrimination factors of C and N for this large carnivore of broad conservation interest. Using the estimated diet in our controlled system and data from a published study on wild wolves and their prey in Montana, USA, we then investigated the simultaneous effect of discrimination factors and prior information on diet reconstruction with Bayesian SIMMs. Discrimination factors for gray wolves and their prey were 1.97‰ for δ13C and 3.04‰ for δ15N. Specifying wolf discrimination factors, as opposed to the commonly used red fox (Vulpes vulpes) factors, made little practical difference to estimates of wolf diet, but prior information had a strong effect on bias, precision, and accuracy of posterior estimates. Without specifying prior information in our Bayesian SIMM, it was not possible to produce SIMM posteriors statistically similar to the estimated diet in our controlled study or the diet of wild wolves. Our study demonstrates the critical effect of prior information on estimates of animal diets using Bayesian SIMMs, and suggests species-specific trophic discrimination factors are of secondary importance. When using stable isotope analysis to inform conservation decisions researchers should understand the limits of their data. It may be difficult to obtain useful information from SIMMs if informative priors are omitted and species-specific discrimination factors are unavailable.

Considering sampling approaches when determining carnivore diets: the importance of where, how, and when scats are collected

Understanding the diets of carnivores is often required to inform their management, to conserve their prey, or to minimize depredation of domestic animals. Scat analysis is one of the oldest and most commonly used methods for determining carnivore diets and many accuracy issues associated with scat analysis have been addressed in other studies. Little attention, however, has been given to the questions of where, how, and when scats are sampled in the field and how these factors can affect conclusions about diet. Based on a review of 64 articles, the two most common sites for collecting scats from grey wolves (Canis lupus) are from wolf homesites (i.e., dens and rendezvous sites) and from along roads. Collections from such areas are often combined and interpreted as depictions of a seasonal diet, with no acknowledgment of the inherent problems associated with sampling at different sites. Rather than combining these two samples of scat, however, we were interested in comparing them. In our field study, we supported our hypothesis that the frequency of prey types differs significantly between wolf scats collected along roads and scats collected at wolf homesites and, therefore, would tell different stories about summer wolf diet if scats had only been collected from one of these sites. This difference is likely due to a combination of three interactions of wolf ecology with our sampling design: local prey availability, timing of scat deposition, and movement behavior. This difference is especially of interest when considering three findings from our review: descriptions of sampling design are often omitted, scats collected from different sites are often combined into a single estimate of diet, and scats are often collected opportunistically. Given the results from our field sampling, these three common practices may significantly affect how carnivore diet data should be interpreted. Furthermore, using our own idiosyncratic study as an example, we discuss other common assumptions in the scat diet literature, including assuming that diet is constant across packs and years. To increase the reliability of diet estimates from scats, researchers should clearly articulate where, how, and when they collected scat samples and should discuss the assumptions of the chosen sampling design so that potential biases and inaccuracies can be assessed.

Short-term responses of wolf feeding habits to changes of wild and domestic ungulate abundance in Northern Italy

Long-term changes of wolf feeding habits have been recorded in several parts of its European range and were related to the increase of wild ungulate populations. An increased use of wild prey often is linked to a decrease of predation on livestock, and consequently it can reduce wolf–human conflict and make for easier predator conservation. We analysed wolf diet from scats collected from 2007 to 2012 in a 927.3-km2 area of the Northern Apennines (Northern Italy) to compare the present diet to that recorded in the late 1980s when the area was colonised by wolves, and to examine short-term changes of wolf feeding habits together with annual and seasonal variations of wild and domestic ungulate selection, possibly related to the increase of wild ungulate abundance. We calculated the availability proportions of wild ungulate species from the presence signs recorded on itineraries and those of livestock species from the data on farms of veterinary services. We identified 17 kinds of prey, pooled into six categories, of which wild ungulates (70%) and livestock (20%) were the most important. During the study period, we observed a reduction in the diet breadth of wolves, to a greater use of wild ungulates, depending on the increase in the availability of wild prey species. Significant seasonal variations were observed in the trophic habits of the wolf, but generally there was a wide use of wild ungulates, especially wild boars. Livestock was mainly used in summer, which corresponds to the period of greatest presence of domestic ungulates on the pastures. Considering the study period, a fast response of wolf feeding habits to the increase of wild ungulate species resulted, together with changes in selection patterns. The change in diet towards a greater use of wild ungulates is an important step in the recovery and conservation of the wolf.

Development of an Ungulate Mammalian Hair Key

We have created a dichotomous hair key to differentiate between adult and juvenile ungulates seen in summer wolf diets; however we would like to stress that this key can also be used for other large carnivore diets, as it has shown merit in the identification of cougar and coyote prey items. To our knowledge there is no mammalian hair key that is able to sufficiently differentiate between juvenile and adults of the major species in the North American Wolf’s (Canis lupus) diet, specifically, mule deer, white-tailed deer, elk, moose and bighorn sheep. We acquired juvenile hair samples starting at birth at bi-weekly to monthly intervals from various zoos, wildlife parks and rehabilitation centres over North America for all the major prey species except bighorn sheep. Main characters used to classify ungulate hair were basal scale margin distance, hair diameter and hair color. Scale margin distance and basal hair diameter was measured via a microscope ocular micrometer, with t-tests completed to assess differences between species. We were successful at differentiating between all juvenile ungulates, however juvenile deer species hair maybe very difficult to differentiate between and may only be accurately done with experience. Juvenile ungulate hair is usually smaller in diam- eter then the guard hair of adults and is more delicate in appearance. As observed in other study by De Marinis et al 2006, we too were able to differentiate juvenile ungulates by a scalloped medulla (Figure 1). We were able to distinguish juvenile moose by their ginger color appearance, large medial hair cuticle scales, and large basal hair diameter compared to other ungulate species (Figure 2). We also found the juvenile elk had smaller hair diameters then juvenile deer and appear less ridged compared to juvenile deer.