Non-invasive acoustic detection of wolves

Monitoring wolves (Canis lupus) is a difficult and often expensive task due to high mobility, pack dynamic, shyness and nocturnal activity of this species. Wolves communicate acoustically through howling, within pack and with packs of the neighbourhood. A wolf howl is a low-frequency vocalization that can be transmitted over long distances and thus it can be used for monitoring. Elicited howling survey is a current method to monitor wolves in different areas all over the world. Elicited howling, however, may be invasive to residential wolf packs and could create possible negative reactions from the human population. Here we show that it is possible to detect wolves by recording spontaneous howling events. We measured the sound pressure level of wolf howls by captive individuals and we further found that elicited howling may be recorded and clearly identified up to a distance of 3 km. We finally conducted a non-invasive acoustic detection of wolves in a free-ranging population. The use of passive sound recorders may provide a powerful non-invasive tool for future wolf monitoring and could help to establish sustainable management plans for this species.     

Environmental and social factors influencing wolf (Canis lupus) howling behavior

Animals communicate in a variety of ways and calls are used for a number of important behaviors. Temperature, wind, time of day, and human activities can affect animals’ use of calls, particularly over long distances. Effects of group size on the use of calls can be particularly influential in territorial social carnivores. Where gray wolves (Canis lupus) are hunted by humans, for example, howling may make it easier for hunters to locate individuals and ultimately increase mortality. We hypothesized that a suite of factors would affect wolves’ responses to simulated howling. Specifically, we predicted that howling behavior would increase with (a) group size, (b) pup age, and (c) during crepuscular time periods and howling behavior would decrease (a) where wolves were harvested and (b) when it was hot or windy. Contrary to our prediction, larger groups did not respond as quickly to simulated wolf howls as smaller groups did and minimum and maximum daily temperatures were not good predictors of wolf howling response rates. Individuals in small litters of pups may have responded more quickly to howls than those in large litters because they are eager to seek safety from and have socialization with adults returning from foraging bouts. Although harvest did not appear to affect vocal communication by wolves, group size, pup age, time of day, wind, and number of howls emitted greatly affected wolves’ behavior and responses during howling surveys. Howling responses did not change because of harvest; response rates from wolves were nearly identical with (2.2%) and without (2.3%) harvest. The year-round benefits of long-distance vocal communication may outweigh the costs of increased mortality arising from howling during harvest season.     

Howling as a Means of Communication in Timber Wolves

The communicatory function of howling was studied in three adultmale timber wolves (Canis lupus). Approximately 700 howls weresubjected to spectrographic and auditory analysis. The fundamentalfrequency of howls was divided into beginning, mid-section,and ending, and each section was studied separately. Harmonicfeatures were also examined. Much variation was found withinthe howls of each individual. However, unique features werefound in all howls of two wolves, of potential value in individualrecognition. The variation in characteristics of the fundamental within howlsof individuals was tested to see if it related to features ofthe animal's behavior or environment. Eleven significant relationshipswere found. The characteristics involved were considered potentiallyfunctional in conveying information of a behavioral or environmentalnature. Auditory discrimination was studied by stimulus-response experimentationinvolving simulated wolf howls by humans. By either howlingin response or remaining silent, one wolf demonstrated an abilityto detect the slight difference between live howls and recorded,played-back howls. This ability enhances the possibility thatindividual recognition and conveyance of information may takeplace by means of differences in howls. Analysis of the circumstances in which spontaneous howling (noknown auditory stimulation) occurred demonstrated that isolationresulted in increased howling. A form of long-distance communication is important to a socialunit whose members are often separated. This study suggeststhat howling identifies the species, functions in the locationof specific animals, provides specific information about thehowling animal, and is, therefore, of great value in coordinatingthe social activities of wolves.     

Howling activity of free-ranging wolves (<Emphasis Type="Italic">Canis lupus</Emphasis>) in the Białowieża Primeval Forest and the Western Beskidy Mountains (Poland)

We investigated spontaneous howling by radio-collared wolves Canis lupus inhabiting the Białowieża Primeval Forest (BPF), eastern Poland, and elicited howling behavior in wolves of the BPF and the Western Beskidy Mountains, southern Poland. Over half (58%) of all spontaneous howls recorded throughout a year occurred in the period from July to October, with a peak in August. The daily pattern of vocal activity by wolves was characterised by a peak between 1800 and 0000 hours, which coincided with the first (dusk) peak of wolf mobility. Wolves howled from the core areas of their territories and not from the peripheries. Howls served as communication between temporarily separated pack mates (43% of cases), after re-union (18%) and before setting out for a hunt (22%). Very few spontaneous howls (2%) were targeted at a neighbouring pack. Wolves responded to human-simulated howling in June–September, with a peak in August (reply rate: 39%). The duration of elicited howling increased significantly with group size: howls by single wolves or pairs lasted, on average, 34–40 s, whereas those of five to seven wolves (including pups) had an average duration of 67–95 s, with a maximum length of nearly 4 min. In the populations of Polish wolves studied here, spontaneous howling served primarily for intra-pack communication. Nonetheless, the high reply rate to howling simulation showed that – if necessary – wolves readily advertised their presence in a territory to strangers.     

CHORUS HOWLING BY WOLVES: ACOUSTIC STRUCTURE,PACK SIZE AND THE BEAU GESTE EFFECT

ABSTRACT

A variety of structural parameters were measured from wolf choruses recorded in the Superior National Forest, Minnesota, USA. Mean duration of 60s did not vary with pack size or composition. Packs replied to simulated howling after an average of 40s, often interrupting the stimulus howls. Choruses began with simply-structured howls, which became increasingly modulated as the chorus progressed. Little difference in mean fundamental frequency or other howl parameters was found among the choruses from packs of various sizes and compositions. In particular, choruses produced by single adult pairs did not differ from those of larger packs accompanied by pups. The lack of relationship between chorus parameters and pack size or composition indicates there is little useful information concerning a pack's size to be found in its chorus howling.

The observation that chorus howling by adult pairs is often perceived as that of larger groups with pups suggests that chorus structure has evolved to exaggerate the apparent size of the pack, especially those newly-established or otherwise reduced in number. If so, wolf howling choruses may represent a mammalian example of the Beau Geste effect, made particularly viable because of the relative immunity of the signal to probing.     

Movements and Home Sites of Timber Wolves in Algonquin Park

Ecological studies of timber wolves (Canis lupus) in a forestedenvironment have always been difficult to undertake in the past,particularly during the summer months, because of the lack ofa suitable technique. In 1960 Pimlott devised a technique whichemployed the use of broadcast wolf howls in locating wolvesin the field. This report reviews the success of this techniquein studying the movements of two packs of wolves, and theiruse of home sites in Algonquin Park, Ontario. Wolves responded by howling a total of 476 occasions or approximately13% of the occasions that broadcast howls were given. Humanimitations were more successful than tape-recordings in inducingresponses. Wolves responded at any time of day, but dusk wasthe most favorable period. They also responded more frequentlyin July and August than in May and June. Two types of home sites were found: the den site, occupied duringthe early life of the pups, and the rendezvous site, a placeoccupied by wolves during later development of pups. All ofhe home sites were adjacent to some immediate source of water.The movement of wolves appeared also to be concentrated alongthe water courses. The locations of the home sites and the evidence obtained fromhowling responses, tracks, and scats suggested that the summerrange comprised a minimum area of eight square miles. The samerange was utilized by a pack in 1961 and 1963.     

Wolf pack rendezvous site selection in Greece is mainly affected by anthropogenic landscape features

In wolves, most offspring mortality occurs within the first 6–8 months of their life. As wolf pups pass this entire period at either the den or rendezvous sites, their selection by wolf packs may affect pup survival and recruitment. Rendezvous sites are important for pup survival as they are used during summer and early autumn, when intense human activity may increase pup mortality. Adult wolves and pups can be killed by livestock guarding dogs during summer and intentionally or accidentally during large game hunting in autumn. This study describes factors related to rendezvous site selection in order to enhance their protection and management. We studied the rendezvous site selection of 30 wolf packs in central and northern Greece between 1998 and 2010, after locating 35 sites using the simulated howling survey method and telemetry. We considered a series of environmental and anthropogenic predictors of wolf rendezvous site selection at two spatial scales. At the landscape-population scale, wolves selected rendezvous sites below 1,200 m asl, with large inter-site distance (mean, 12.9 km), and avoided partially forested or open habitats, indicating preference for covered, spaced areas with seasonally stable resources. At the home range scale, wolves selected rendezvous sites away from forest roads and villages, close to water sources, and in areas with low forest fragmentation, indicating avoidance of human presence and disturbance. In the summer of 2011, we used an ensuing resource selection model (RSF, AUC?=?0.818) to successfully locate seven new rendezvous sites outside our previous survey area, verifying the utility of prediction maps (all new sites were at areas with 0.8–1 model probability). Rendezvous prediction maps can be used to reduce field effort when monitoring wolf populations, assess livestock predation risk, design protected areas, and reduce human disturbance on reproductive wolf packs.     

BIOACOUSTIC PUBLICATIONS, 1987

The use of amplitudes to identify individuals has historically been ignored by bioacoustic researchers due to problems of attenuation. However, recent studies have shown that amplitudes encode identity in a variety of mammal species. Previously, individuality has been demonstrated in both fundamental frequency (F₀) and amplitude changes of captive Eastern wolf (Canis lupus lycaon) howls with 100% accuracy where attenuation of amplitude due to distance was controlled in a captive environment. In this study, we aim to determine whether both fundamental frequency and amplitude data collected from vocalizations of wild wolves recorded over unknown distances, in variable conditions and with different recording equipment, can still encode identity. We used a bespoke code, developed in Matlab, to extract simple scalar variables from 67 high-quality solo howls from 10 wild individuals and 112 chorus howls from another 109 individuals, including lower quality howls with wind or water noise. Principal component analysis (PCA) was carried out on the fundamental frequency and normalized amplitude of harmonic 1, yielding histogram-derived PCA values on which discriminant function analysis was applied. An accuracy of 100% was achieved when assigning solo howls to individuals, and for the chorus howls a best accuracy of 97.4% was achieved. We suggest that individual recognition using our new extraction and analysis methods involving fundamental frequency and amplitudes together can identify wild wolves with high accuracy, and that this method should be applied to surveys of individuals in capture–mark–recapture and presence–absence studies of canid species.     

The effect of female call on male howling in red howler monkeys(Alouatta seniculus)

Howler (Alouatta spp.)females often produce loud calls together with the males. Sometimes these howls are not heard above the much louder male call, but on other occasions most of the howls are produced by the females. Observations indicate that female howls are aggressive. Females howl at other troop females and at extratroop females; they also sit close to their mates and howl at other males. I suggest that howling by the females with their mate is important in strengthening the pair bond whereby the male recognizes his infants and acts protectively toward them. Playback experiments of female howls elicited more response from the males than did recordings of male/female and male-only howls, supporting the hypothesis that females howl in order to incite competition among the males.     

THE ACOUSTIC STRUCTURE OF WOLF HOWLS IN SOME EASTERN TUSCANY (CENTRAL ITALY) FREE RANGING PACKS

ABSTRACT

Italian wolf howls are described for the first time from observations between 2003–2008 of a population living in eastern Tuscany, central Italy. A sample of 37 howls selected among single responses and 128 howls included in the choruses of 7 free ranging packs was recorded and analysed. The mean fundamental frequency of the howls ranged between 274–908 Hz. Two main structures recognised by means of multivariate explorative analysis, in particular Principal Component and Cluster Analysis, were ascribed to breaking and flat howls. Discriminant Function Analysis was applied to the recognised groups with the aim to find a general rule for classification. Howls with different features were correctly assigned to the groups obtained by explorative analysis in 95.8% of cases. The analysis of the variables characterising the structure of the howls suggests that maximum frequency and range of fundamental frequency are the most important parameters for classification, while duration does not appear to play any significant role.     

Estimation of Successful Breeding Pairs for Wolves in the Northern Rocky Mountains,USA

Abstract: Under the Endangered Species Act, documenting recovery and federally mandated population levels of wolves (Canis lupus) in the Northern Rocky Mountains (NRM) requires monitoring wolf packs that successfully recruit young. United States Fish and Wildlife Service regulations define successful breeding pairs as packs estimated to contain an adult male and female, accompanied by ≥2 pups on 31 December of a given year. Monitoring successful breeding pairs will become more difficult following proposed delisting of NRM wolves; alternatives to historically intensive methods, appropriate to the different ecological and regulatory context following delisting, are required. Because pack size is easier to monitor than pack composition, we estimated probability a pack would contain a successful breeding pair based on its size for wolf populations inhabiting 6 areas in the NRM. We also evaluated the extent to which differences in demography of wolves and levels of human-caused mortality among the areas influenced the probability of packs of different sizes would contain successful breeding pairs. Probability curves differed among analysis areas, depending primarily on levels of human-caused mortality, secondarily on annual population growth rate, and little on annual population density. Probabilities that packs contained successful breeding pairs were more uniformly distributed across pack sizes in areas with low levels of human mortality and stable populations. Large packs in areas with high levels of human-caused mortality and high annual growth rates had relatively high probabilities of containing breeding pairs whereas those for small packs were relatively low. Our approach can be used by managers to estimate number of successful breeding pairs in a population where number of packs and their sizes are known. Following delisting of NRM wolves, human-caused mortality is likely to increase, resulting in more small packs with low probabilities of containing breeding pairs. Differing contributions of packs to wolf population growth based on their size suggests monitoring successful breeding pairs will provide more accurate insights into population dynamics of wolves than will monitoring number of packs or individuals only.     

The Effects of Breeder Loss on Wolves

Abstract Managers of recovering wolf (Canis lupus) populations require knowledge regarding the potential impacts caused by the loss of territorial, breeding wolves when devising plans that aim to balance population goals with human concerns. Although ecologists have studied wolves extensively, we lack an understanding of this phenomenon as published records are sparse. Therefore, we pooled data (n = 134 cases) on 148 territorial breeding wolves (75 M and 73 F) from our research and published accounts to assess the impacts of breeder loss on wolf pup survival, reproduction, and territorial social groups. In 58 of 71 cases (84%), ≥1 pup survived, and the number or sex of remaining breeders (including multiple breeders) did not influence pup survival. Pups survived more frequently in groups of ≥6 wolves (90%) compared with smaller groups (68%). Auxiliary nonbreeders benefited pup survival, with pups surviving in 92% of cases where auxiliaries were present and 64% where they were absent. Logistic regression analysis indicated that the number of adult-sized wolves remaining after breeder loss, along with pup age, had the greatest influence on pup survival. Territorial wolves reproduced the following season in 47% of cases, and a greater proportion reproduced where one breeder had to be replaced (56%) versus cases where both breeders had to be replaced (9%). Group size was greater for wolves that reproduced the following season compared with those that did not reproduce. Large recolonizing (>75 wolves) and saturated wolf populations had similar times to breeder replacement and next reproduction, which was about half that for small recolonizing (≤75 wolves) populations. We found inverse relationships between recolonizing population size and time to breeder replacement (r= —0.37) and time to next reproduction (r= —0.36). Time to breeder replacement correlated strongly with time to next reproduction (r=0.97). Wolf social groups dissolved and abandoned their territories subsequent to breeder loss in 38% of cases. Where groups dissolved, wolves reestablished territories in 53% of cases, and neighboring wolves usurped territories in an additional 21% of cases. Fewer groups dissolved where breeders remained (26%) versus cases where breeders were absent (85%). Group size after breeder loss was smaller where groups dissolved versus cases where groups did not dissolve. To minimize negative impacts, we recommend that managers of recolonizing wolf populations limit lethal control to solitary individuals or territorial pairs where possible, because selective removal of pack members can be difficult. When reproductive packs are to be managed, we recommend that managers only remove wolves from reproductive packs when pups are ≥6 months old and packs contain ≥6 members (including ≥3 ad-sized wolves). Ideally, such packs should be close to neighboring packs and occur within larger (≥75 wolves) recolonizing populations.     

Surveying Predicted Rendezvous Sites to Monitor Gray Wolf Populations

ABSTRACT We used rendezvous site locations of wolf (Canis lupus) packs recorded during 1996–2006 to build a predictive model of gray wolf rendezvous site habitat in Idaho, USA. Variables in our best model included green leaf biomass (Normalized Difference Vegetation Index), surface roughness, and profile curvature, indicating that wolves consistently used wet meadow complexes for rendezvous sites. We then used this predictive model to stratify habitat and guide survey efforts designed to document wolf pack distribution and fecundity in 4 study areas in Idaho. We detected all 15 wolf packs (32 wolf pack-yr) and 20 out of 27 (74%) litters of pups by surveying <11% of the total study area. In addition, we were able to obtain detailed observations on wolf packs (e.g., hair and scat samples) once we located their rendezvous sites. Given an expected decrease in the ability of managers to maintain radiocollar contact with all of the wolf packs in the northern Rocky Mountains, rendezvous sites predicted by our model can be the starting point and foundation for targeted sampling and future wolf population monitoring surveys.     

Wolf Depredation on Domestic Animals in the Polish Carpathian Mountains

Abstract As wolves (Canis lupus) recover in Poland, their depredation on domestic animals is increasing, as have conflicts between wolves and farmers. From 1998 to 2004, I investigated spatial and temporal patterns of 591 verified incidents of wolf depredation in the eastern part of the Polish Carpathian Mountains. The wolf population I surveyed covered an estimated range of 4,993 km². Depredation occurred over 1,595 km² of that area. Sheep accounted for 84.8% of domestic animals killed by wolves. Depredation on sheep and number of sheep farms attacked by wolves increased between 1998 and 2004 (r² = 0.61, P = 0.04 and r² = 0.89, P = 0.02, respectively). The number of wolf attacks on sheep farms in a given year were negatively correlated to red deer (Cervus elaphus) population numbers (R² = 0.69, P = 0.02). The amount of depredation caused by each of the 4 monitored packs was best explained by farm density in their territories (R² = 0.59, P = 0.004). Number of attacks recorded on farms was positively correlated to distance from the farm to the pack's den and rendezvous sites (R² = 0.16, P = 0.04). Of depredation recorded in the 4 pack's territories I surveyed, 77% occurred in 4 farms with no or inadequate protection. I concluded that wolf depredation in the studied area is opportunistic. Wolf predation intensity is a function of decreasing abundance of red deer, the density of sheep farms, and proximity of farms to the summer activity centers of wolf packs, and it is facilitated by poor husbandry practices. These results can aid in preventing wolf depredation and provide a foundation for a wolf management plan.     

Wolf monitoring in Scandinavia: evaluating counts of packs and reproduction events

Large carnivores are elusive and use large areas, which causes monitoring to be challenging and costly. Moreover, management to reduce conflicts and simultaneously ensure long-term population viability require precise population estimates. In Scandinavia, the monitoring of wolves (Canis lupus) is primarily based on counting packs, identifying reproduction, and genetically identifying territorial wolves from noninvasive DNA samples. We assessed the reliability of wolf monitoring in Scandinavia by estimating the detectability of territorial pairs, packs, and reproduction. Our data, comprising snow-tracking data and DNA-identified individuals from 2005–2016, covered 11 consecutive winter monitoring seasons (Oct–Mar). Among 343 cases where we identified a wolf pack, territorial wolves were also detected in the same area during the previous season in 323 (94.2%) cases. In only 6 of the remaining 20 cases, there was no prior knowledge of territorial wolves in the area. Among the 328 detected reproduction events (litter born to a pack), we detected 97% during the monitoring period and identified the rest ≥1 year later from kinship assessments of all DNA-detected individuals. These results suggest that we failed to detect only few packs with reproduction events during the monitoring season that followed breeding. Yearly monitoring of territorial individuals and continuous updates of the pedigree allowed us to retrospectively identify reproduction events and packs that were not identified earlier.     

Effects of wolf pack size and winter conditions on elk mortality

Elk (Cervus canadensis) are high-profile game animals for many states in the western United States, yet over the past several decades some populations have experienced a persistent and broad-scale decline in recruitment. Over this same period, gray wolves (Canis lupus) have become an integral component of many western landscapes and agencies are increasingly challenged to maximize hunting opportunities of ungulates via predator management while simultaneously ensuring wolf conservation. To better understand the implications of predator management on elk populations, we monitored survival of 1,244 adult female elk and 806 6-month-old calves from 29 populations distributed throughout Idaho, USA, from 2004 to 2016. We developed predictive models of mortality that related mortality risk to wolf pack size, winter conditions, and individual-level characteristics. Annual mortality rates (excluding harvest) for adult females and calves were 0.09 and 0.40, respectively. Calf mortality was predicted best with a model that included additive effects of chest girth at time of capture, mean size of surrounding wolf packs, and snow depth. Adult female mortality was predicted best with a model that included female age, mean size of surrounding wolf packs, and snow depth. Based on a sensitivity analysis, chest girth had the largest effect on risk of mortality for calves followed by pack size and snow depth. Other than the effect of senescence in the oldest (>15 yr) individuals, pack size and snow depth had the largest effect on risk of mortality for adult females. We estimated cause-specific mortality and predation was the dominant cause of known-fate mortalities for adult females (35% mountain lion [Puma concolor] and 32% wolf) and calves (45% mountain lion and 28% wolf), whereas malnutrition accounted for 9% and 10% of adult female and calf mortalities, respectively. Wolves preferentially selected smaller calves and older adult females, whereas mountain lions showed little preference for calf size or age class of adult females. Our study indicates managers can increase elk survival by reducing wolf pack sizes on surrounding winter ranges, especially in areas where, or during years when, snow is deep. Additionally, managers interested in improving over-winter calf survival can implement actions to increase the size of calves entering winter by increasing the nutritional quality of summer and early fall forage resources. Although our study was prompted by management questions related to wolves, mountain lions killed more elk than wolves and differences in selection of individual elk indicate mountain lions may have comparably more of an effect on elk population dynamics. Although we were unable to relate changes in mountain lion populations to elk survival in our study, future research should seek a better understanding of multi-predator systems, including how management of one predator affect others and ultimately how these interactions affect elk survival. © 2019 The Wildlife Society     

Spatial organization in the Ethiopian wolf Canis simensis: large packs and small stable home ranges

The spatial organization of the rare Ethiopian wolf ( Canis simensis ) was studied in the Afroalpine heathlands of Bale Mountains National Park, southern Ethiopia, between 1988 and 1992. Nineteen animals were radio-tracked, 48 ear-tagged and 64 others recognized by coat patterns and observed directly. Dry season (October—March) home ranges of resident wolves covered between 2 and 15 km². The ranges of adult males were slightly larger than those of females, and subadults' home ranges were slightly smaller than those of adults. The population density of the wolves was correlated with prey biomass. In optimal habitat, wolves lived in packs of 3—13 adults (mean 5.9 wolves > 1year old) containing several close-kin males; adult sex ratio favoured males 1.88: 1 and combined pack home ranges averaged 6.0km². In an area of lower prey productivity, wolves lived in pairs or small groups (mean 2.7), adult sex ratio was 1:1 and home ranges averaged 13.4 km².
Home ranges overlapped extensively (mean 85%) between members of the same pack. Four to seven percent of the population was additionally composed of non-resident females, inhabiting larger ranges (mean 11.1 km²). Home ranges of neighbouring packs were largely discrete, forming a tessellating mosaic of packs occupying all available habitat. Pack home ranges were stable in time, drifting only during major pack readjustment after the disappearance of a pack or significant demographic changes. Ethiopian wolf home ranges were smaller than would be expected for a carnivore of its size and sociality, presumably as a result of the high rodent productivity of the Afroalpine ecosystem.     

Efficient,Noninvasive Genetic Sampling for Monitoring Reintroduced Wolves

ABSTRACT Traditional methods of monitoring gray wolves (Canis lupus) are expensive and invasive and require extensive efforts to capture individual animals. Noninvasive genetic sampling (NGS) is an alternative method that can provide data to answer management questions and complement already-existing methods. In a 2-year study, we tested this approach for Idaho gray wolves in areas of known high and low wolf density. To focus sampling efforts across a large study area and increase our chances of detecting reproductive packs, we visited 964 areas with landscape characteristics similar to known wolf rendezvous sites. We collected scat or hair samples from 20% of sites and identified 122 wolves, using 8–9 microsatellite loci. We used the minimum count of wolves to accurately detect known differences in wolf density. Maximum likelihood and Bayesian single-session population estimators performed similarly and accurately estimated the population size, compared with a radiotelemetry population estimate, in both years, and an average of 1.7 captures per individual were necessary for achieving accurate population estimates. Subsampling scenarios revealed that both scat and hair samples were important for achieving accurate population estimates, but visiting 75% and 50% of the sites still gave reasonable estimates and reduced costs. Our research provides managers with an efficient and accurate method for monitoring high-density and low-density wolf populations in remote areas.     

Territory size of wolves Canis lupus: linking local (Białowieża Primeval Forest, Poland) and Holarctic-scale patterns

Factors affecting territory size in wolves Canis lupus were studied at 2 scales, the local population (Bia?owie?a Primeval Forest (BPF), eastern Poland) and the geographic range of species (literature review from 14 localities in the Holarctic). Four packs of wolves were studied by radio‐tracking in BPF from 1994 to 1999. The annual territories of packs (Minimum convex polygons with 95% of locations) averaged 201 km² (SD 63, range 116–310). Core areas of territories (50% MCP) covered from 14 to 78 km² (mean 35). Territory sizes and core areas both were negatively correlated to the encounter rates of ungulates (mean number of ungulates seen per unit time spent in the forest by human observers). Pack size (3–8 wolves) did not influence territory size. Home ranges of individual wolves from the same pack varied with season as well as the age, sex, and reproductive status of the wolf. Review of literature from North America and Europe (42–66^oN), showed that latitude and prey biomass were essential factors shaping the biogeographic variation in wolf territory size. Territories increased with latitude and declined with growing biomass of prey. The analysis showed that latitude acted partly independently of the south–north gradient in prey abundance. At similar standing crop of ungulate biomass (100 kg km^?2), wolf territories would average 140 km² at 40^oN, 370 km² at 50^oN, and 950 km² at 60^oN. Pack size was larger at northern latitudes, but the increase did not keep pace with enlargement of territories. Within‐territory density of wolves declined from 2.5–3 wolves 100 km^?2 at 40–45^oN to 0.7 wolves 100 km^?2 at 60^oN. Our analyses documented similarities regarding the role of prey resources in shaping wolf territoriality at the different scales. Furthermore, a macroecological approach revealed additional factors affecting wolf territory size that were not emergent from knowledge of local population.     

Inter-pack,seasonal and annual variation in prey consumed by wolves in Pollino National Park,southern Italy

Although understanding of food habits of wolves in human-modified landscapes is critical to inform conservation and conflict management, no such studies have ever been conducted in the southern Apennines, Italy, where wolves long coexisted with humans. By means of scat analysis (n?=?1743) and log-linear modelling, we investigated diet composition in five wolf packs in the relatively simple prey system of the Pollino National Park (PNP), southern Italy (1999?2003). Overall, although wild boar was the most frequently consumed prey (mean frequency ± SD, 63.1?±?23%), both wild boar and cattle predominated the diet in terms of biomass (45.3?±?24 and 48.1?±?21%, respectively). We revealed, however, a zonal (i.e. area, pack) followed by annual and seasonal effects on the wolf diet. Cattle consumption by wolf packs in the northern portion of PNP (Pollino subrange) was highest, especially during summer when cattle predominated the diet in terms of biomass (68.3?±?20%). Instead, wild boar consumption was highest in the Orsomarso packs (biomass, 62.1?±?13%), with increasing trends throughout the study period but no relevant seasonal variation. Wild boar piglets and cattle calves were the most frequently consumed age classes, revealing their availability year-round and higher profitability compared to other prey. Cattle consumption by wolves reflected prevailing husbandry techniques (free-ranging herds with unattended births) and determined a permanent state of conflict, often spurring retaliatory killing of wolves. Compatible cattle husbandry practices, along with the restoration of multi-prey communities, are needed to reduce wolf-livestock conflicts and possibly enhance the ecological role of wolves in human-altered ecosystems.