Abstracts

Daily Movements and Territory Use by Radio-collared Wolves (Canis lupus) in Bialowieza Primeval Forest in Poland

Jedrzejewski, W.; Schmidt, K.; Theuerkauf, J.; Jedrzejewski, B.; Okarma, H., Canadian Journal of Zoology, 79/11(November 2001), 1993 (12pp)

Wolves (Canis lupus) (9 females and 2 males from 4 packs), were radio-tracked in a large Polish woodland in Bialowieza Primeval Forest in 1996–1999. Based on 360 days of radio tracking with locations taken at 30- or 15-min intervals, daily movement distances (DMDs) of wolves and their utilization of territories were analyzed. DMDs averaged 22.1 km for females and 27.6 km for males. In reproductive and subadult females, DMDs varied seasonally, with the shortest daily routes in May and the longest in autumn–winter. Little seasonal variation was observed in nonbreeding and unsuccessfully breeding adult females. An adult male covered the longest DMDs in February (mating season). The mean speed of travelling wolves was 2.2 km/h. Wolves' hunting activity affected the length and speed of their movements, both of which were higher before than after a kill was made. With growing abundance of prey, DMDs of wolves became shorter. Snow cover and rainfall had a negligible effect on wolf travel. The mean straight-line distance between consecutive daily locations (SLD) was 4.4 km, i.e., on average, 21% of the actual route covered by wolves. Daily ranges utilized by wolves averaged 21.4 km[sup 2] , or 9% of the whole territory. Variation in SLDs and daily ranges was shaped predominantly by mating, breeding, and pup rearing. The pattern of territory use by wolves differed between seasons. In spring–summer, their movements concentrated around the breeding den and rendezvous sites, and the areas used on consecutive days overlapped extensively. In autumn–winter, wolves moved widely and utilized their territory in a rotational way, returning to the same parts every 6 days, on average. Rotational use is related to intense patrolling and defense of territory, but may also help wolves to avoid behavioral depression of prey availability.

Demography of a Recovering Wolf Population in the Yukon

Hayes, R.; Harestad, A., Canadian Journal of Zoology, 78 (January 2000): 36-48 (13 pp)

We studied the dynamics of a wolf (Canis lupus) population recovering from intensive reduction in the Finlayson Lake area, Yukon, Canada. Within 6 years, numbers increased from 29 wolves, then stabilized at 245. The colonization of vacant territories by young wolf pairs was the primary mechanism of early population recovery. Reproduction and a low dispersal rate increased pack size in later years, and pack splitting allowed dispersing wolves to remain near natal packs. The rate of increase in the wolf population was density-dependent and related to wolf density, but was also related to the dispersal rate. The dispersal rate was density-independent and related to mean pack size and prey biomass : wolf index. The survival rate was age-dependent and not related to wolf density. In the early years of recovery, the rate of increase was supported by high survival rates and low dispersal rates. In later years, dispersal rates increased, stabilizing mean pack size and wolf density. Wolf density stabilized at levels predicted by the prey supply, but whether the wolf population is regulated by the availability of prey resources remains unresolved. Wolf density, pack density, and mean pack size were similar in 1983 and 1996, despite a 2- to 3-fold difference in prey biomass. We suggest that the interaction of wolf density and mean pack size in stable prey systems needs to be studied to determine the roles played by food supply and wolf social behavior in regulating wolf abundance.

Density Dependent Matrix Model for Gray Wolf Population Projection.

Miller, D.H.; Jensen, A.L.; Hammill, J.H., Ecological Modelling, 151(June 2002), 271 (8pp)

A Leslie matrix model was developed for a small gray wolf (Canis lupus) population recolonizing an area with abundant resources and uncontrolled by humans. The model was modified to describe population growth in a limited environment using a discrete form of the logistic equation. The density dependent Leslie matrix model was applied to investigate gray wolf population recovery in the Upper Peninsula of Michigan. Estimates from the density dependent matrix model were compared with published winter count estimates from the Michigan Department of Natural Resources. The gray wolf population in the Upper Peninsula of Michigan was projected to reach a total of 929 wolves by the year 2012 with a 95% confidence interval of 662 to 1153 wolves.

Detecting Rare Introgression of Domestic Dog Genes into Wild Wolf (Canis lupus) Populations by Bayesian Admixture Analyses of Microsatellite Variation

Randi, E.; Lucchini, V., Conservation Genetics, 3/1 (2002), 29-43 (15 pp)

Hybridization with free-ranging dogs is thought to threat the genetic integrity of wolves in Europe, although available mtDNA data evidenced only sporadic cases of crossbreeding. Here we report results of population assignment and genetic admixture analyses in 107 wild-living Italian wolves, 95 dogs including 30 different breeds and feral dogs, and captive-reared wolves of unknown or hybrid origins, which were genotyped at 18 microsatellites. Two Italian wolves showed unusually dark coats ("black wolves''), and one showed a spur in both hindlegs ("fifth finger wolf''), suggesting hybridization. Italian wolves showed significant deficit of heterozygotes, positive F _IS values and deviations from Hardy-Weinberg equilibrium. Genetic variability was significantly partitioned between groups, suggesting that wolves and dogs represent distinct gene pools. Multivariate ordination of individual genotypes and clustering of inter-individual genetic distances split wolves and dogs into two different clusters congruent with the prior phenotypic classification, but hybrids and wolves of unknown origin were not identified from genetic information alone. By contrast, a Bayesian admixture analysis assigned all the Italian wolves and dogs to two different clusters, independent of any prior phenotypic information, and simultaneously detected the admixed gene composition of the hybrids, which were assigned to more than one cluster. Captive-reared wolves of unknown origin were prevalently assigned to the Italian wolf population. Admixture analyses showed that one ``black wolf'' had mixed ancestry in the dog gene pool and could be a hybrid, while the other two wolves with unusual phenotypes were assigned to the Italian wolf population.

Diet Composition of Wolves (Canis lupus) in the Northeastern Qinghai-Tibet Plateau, China

Liu, B.W.; Jiang, Z.G., Acta Theriologica, 48/2, June 2003, 255-263

From August 1998 to August 2001, 119 wolf scats were collected from the desert in a pastoral region in northeastern Qinghai-Tibet Plateau, China. The study area is the last habitat for the critically endangered Przewalski's gazelle Procapra przewalskii. Wolf predation was hypothesized as a cause of the endangerment of the Przewalski's gazelle. The diet of wolf during the plant green period (June-September) and the plant withering period (October-May) were determined using three scat-analysis methods: frequency of occurrence, mass in scats and the ingested biomass obtained with the linear regression models of Weaver (1993). Limited to mammalian prey, total agreement was found between the dry weight and biomass methods, but less so between the frequency of occurrence data and other methods. Hare, yak, and small rodents were the important prey species of the wolves during the plant green period, each accounting for 33, 27, and 20%. Yak, sheep and hare were the important prey species during the plant withering period, each accounting for 53, 25, and 17%. Other food types were badger, Przewalski's gazelle, birds, reptiles, invertebrates and plants. The presence of the livestock remains in the wolf's scats may imply scavenging behavior by the wolves, because few cases of missing livestock were reported during the study. No notable seasonal difference in the diet composition of the wolves was found. The food niche of wolf during the plant green period (0.55 +/- 0.02) was similar to that during the plant withering period (0.50 +/- 0.02).

DNA Profiles of the Eastern Canadian Wolf and the Red Wolf Provide Evidence for A Common Evolutionary History Independent of the Gray Wolf

Wilson, Paul ; Grewal, Sonya ; Lawford, Ian ; Heal, Jennifer ; Granacki, Angela ; Pennock, David ; Theberge, John ; Theberge, Mary ; Voigt, Dennis ; Waddell, Will ; Chambers, Robert ; Paquet, Paul ; Goulet, Gloria ; Cluff, Dean ; White, Bradley, Canadian Journal of Zoology, 78 (December, 2000): 2156-2166 (11 pp)

The origin and taxonomy of the red wolf (Canis rufus) have been the subject of considerable debate and it has been suggested that this taxon was recently formed as a result of hybridization between the coyote and gray wolf. Like the red wolf, the eastern Canadian wolf has been characterized as a small "deer-eating" wolf that hybridizes with coyotes (Canis latrans). While studying the population of eastern Canadian wolves in Algonquin Provincial Park we recognized similarities to the red wolf, based on DNA profiles at 8 microsatellite loci. We examined whether this relationship was due to similar levels of introgressed coyote genetic material by comparing the microsatellite alleles with those of other North American populations of wolves and coyotes. These analyses indicated that it was not coyote genetic material which led to the close genetic affinity between red wolves and eastern Canadian wolves. We then examined the control region of the mitochondrial DNA (mtDNA) and confirmed the presence of coyote sequences in both. However, we also found sequences in both that diverged by 150 000 - 300 000 years from sequences found in coyotes. None of the red wolves or eastern Canadian wolf samples from the 1960s contained gray wolf (Canis lupus) mtDNA sequences. The data are not consistent with the hypothesis that the eastern Canadian wolf is a subspecies of gray wolf as it is presently designated. We suggest that both the red wolf and the eastern Canadian wolf evolved in North America sharing a common lineage with the coyote until 150 000 - 300 000 years ago. We propose that it retain its original species designation, Canis lycaon.

Do Wolves Affect White-tailed Buck Harvest in Northeastern Minnesota?

Mech, L.D.; Nelson, M.E., Journal of Wildlife Management, 64/1 (January 2000)

We used simple linear regression to analyze 8-23 years of data on a wolf (Canis lupus) population and human harvest of white-tailed deer (Odocoileus virginianus) bucks in northeastern Minnesota to determine any effects of wolves on buck harvesting. Over the long term, wolves accounted for at least 14-22% of the inter-year variation in buck harvest in the region, but an unknown amount of variation in hunter effort may have obscured any more precise estimate.

Dynamics of Early Wolf and Cougar Eradication Efforts in Montana: The Implications for Conservation

Riley, S.K.; Nesslage, G.M.; Maurer, B.A., Biological Conservation, 119/4 (October 2004), 575 (5 pp)

Bounty records from Montana (1902-1930) were used to better understand spatial and temporal responses of wolves (Canis lupus) and cougars (Puma concolor) to an eradication program. Number of payments for wolves declined from a high of 4116 in 1903 to 0 by 1928. Numbers of cougar pelts fluctuated, but generally declined from 177 in 1908 to 2 in 1930. An inverse spatial relationship existed between density of payments for wolves and cougars. Payments for wolves were greatest in the Montane. The ratio of pup to adult wolves also were greatest in the Prairie ecoregion and least in the montane. If distribution and frequency of bounty payments were a reflection of the distribution and abundance of wolves, populations were highest and most productive in areas where they currently do not occur.