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Wolves
Wolf History, Conservation, Ecology and Behavior
[www.wolfology.com]
Kill Rate by Wolves on Moose in the Yukon
Hayes, Baer, Wotschikowsky & Harestad, Canadian Journal of Zoology, 78 (January 2000): 49-59 (11 pp)
We studied the kill rate by wolves (Canis lupus) after a large-scale wolf removal when populations of wolves, moose (Alces alces), and woodland caribou (Rangifer tarandus caribou) were all increasing. We followed a total of 21 wolf packs for 4 winters, measuring prey selection, kill rates, and ecological factors that could influence killing behavior. Wolf predation was found to be mainly additive on both moose and caribou populations. Kill rates by individual wolves were inversely related to pack size and unrelated to prey density or snow depth. Scavenging by ravens decreased the amount of prey biomass available for wolves to consume, especially for wolves in smaller packs. The kill rate by wolves on moose calves was not related to the number of calves available each winter. Wolves did not show a strong switching response away from moose as the ratio of caribou to moose increased in winter. The predation rate by wolves on moose was best modeled by the number and size of packs wolves were organized into each winter.
Large Predators in Small Parks: Wolves in La Mauricie National Park
Villemure, World Wolf Congress 2003
The role of small protected areas in the conservation of wolves is unclear. We documented reproduction, survival, dispersal and recruitment inside and outside La Mauricie National Park, Quebec. We examined the consequences for wolf ecology of a patchwork of areas with different wildlife management and land-use practices. We wanted to test if this small Park (536 km2) could be a source of wolves for surrounding areas, where wolves are hunted and trapped. We monitored movements and behavior of wolves using radio telemetry. Since April 2000, we have radiocollared sixteen wolves, of which all but 5 were killed by trappers. Trapping mortality of radiocollared wolves was 33% a year. Of 4 wolves radiocollared in the Park, 3 were killed outside the protected area. The Park area is equivalent to the home range of a single pack, but no pack has its entire home range protected by the Park. Although large protected areas may play a key role in the conservation of large carnivores, it appears that a small protected area like La Mauricie is insufficient to have any impact on wolf populations.
Leadership Behavior in Relation to Dominance and Reproductive Status in Gray Wolves, Canis lupus
Peterson, Jacobs, Drummer, Mech & Smith, Canadian Journal of Zoology, 80 (August 2002): 1405-1412 (8 pp)
We analyzed the leadership behavior of breeding and nonbreeding gray wolves (Canis lupus) in three packs during winter in 19971999. Scent-marking, frontal leadership (time and frequency in the lead while traveling), initiation of activity, and nonfrontal leadership were recorded during 499 h of ground-based observations in Yellowstone National Park. All observed scent-marking (N = 158) was done by breeding wolves, primarily dominant individuals. Dominant breeding pairs provided most leadership, consistent with a trend in social mammals for leadership to correlate with dominance. Dominant breeding wolves led traveling packs during 64% of recorded behavior bouts (N = 591) and 71% of observed travel time (N = 64 h). During travel, breeding males and females led packs approximately equally, which probably reflects high parental investment by both breeding male and female wolves. Newly initiated behaviors (N = 104) were prompted almost 3 times more often by dominant breeders (70%) than by nonbreeders (25%). Dominant breeding females initiated pack activities almost 4 times more often than subordinate breeding females (30 vs. 8 times). Although one subordinate breeding female led more often than individual nonbreeders in one pack in one season, more commonly this was not the case. In 12 cases breeding wolves exhibited nonfrontal leadership. Among subordinate wolves, leadership behavior was observed in subordinate breeding females and other individuals just prior to their dispersal from natal packs. Subordinate wolves were more often found leading packs that were large and contained many subordinate adults.
Linking Social Behaviour to a Population Viability Analysis for Wolves
Callaghan, Vucetich, Kucz & Paquet, World Wolf Congress 2003
Small populations of wolves are vulnerable to decline due to stochastic processes and deterministic effects of human-caused mortality may be important for wolves because of their low densities and wide-ranging movements. Dispersal behaviour and social organization also may have important consequences for population persistence of wolves. We developed an individual-based, age-structured, spatially-implicit stochastic simulation model to investigate interaction of social dynamics and population parameters in a population of wolves occupying the Central Rocky Mountains, Canada. Radio-telemetry studies and den site observations in the study area over 14 years provided information on population parameters. Model simulations indicated a relatively low probability (0.14) of extinction under current conditions. Population carrying capacity, number of immigrations, maximum litter size, and severity of catastrophe accounted for the greatest variability in probability of extinction. Simulations in which emigration from and immigration into protected areas did not occur resulted in a high probability (0.82) of population extinction. The ranging behaviour of this wolf population and the topographical complexity of the region increase edge effects by exposing wolves to risks of mortality along the borders of protected reserves. Consequently, protected areas within the region are too small to maintain population persistence without relying on immigrants from outside of protected reserves.
Livestock Guarding Dogs and Their Modern Role in Large Carnivore Conservation Initiatives
Rigg, Gorman & Sillero-Zubiri, World Wolf Congress 2003
Livestock guarding dogs (LGDs) have been raised for millenia to protect domesticated animals from wild predators, stray/feral dogs and thieves. We reviewed their use in modern times and found that it has declined in many regions for several reasons. Some LGD breeds are rare, others have been bred for show, crossbred or misused in ways that have weakened their working ability. Nevertheless[,] in parts of Italy and Romania the LGD tradition survives largely intact. Elsewhere, e.g. Slovakia and Poland, systematic efforts are being made to increase use of LGDs to support large carnivore conservation. LGDs have also been tested in countries where they are not traditional, e.g. in Norway, Namibia and the USA. LGDs are especially appropriate when rare, endangered and legally protected carnivores are causing damage to livestock. Many LGD projects therefore operate in conjunction with carnivore conservation initiatives that, when funding and assistance can be provided, help offset farmers' start-up costs. One such initiative is the Protection of Livestock and Conservation of Large Carnivores project, running in Slovakia since 2000. Traditional use of LGDs in Slovakia was mostly abandoned in the first half of the 20th century, at a time when large carnivores had been virtually extirpated. Losses of sheep, goats and cattle to wolves (Canis lupus) and brown bears (Ursus arctos) subsequently increased as their populations naturally recovered. Hostility due to livestock depredation, especially to wolves, is greather than losses, which remain relatively low in Slovakia...and affect a minority of farms, so effective prevention might reduce conflict and increase acceptance of large carnivores.
Lone Wolf to the Rescue
Ingvarsson, Nature, 420 (5 December 2002), 472
Cites the results of a study showing that the population of grey wolf in Scandinavia was significantly influenced by the arrival of a single immigrant wolf. Influence of the lack of genetic diversity on delimiting the size of the wolf population; Decimation of the Scandinavian grey wolves in the 19th and 20th centuries; Correlation between the increase and the immigration of a single male wolf of Finnish or Siberian origin.
Long-Distance Wolf Recolonization of France and Switzerland Inferred from Non-Invasive Genetic Sampling Over a Period of 10 Years
Valiere, Fumagalli, Gielly, Miquel, Lequette, Poulle, Weber, Arlettaz & Taberlet, Animal Conservation 6/1, February 2003, 83-92
In the early 1900s, the wolf (Canis lupus) was extirpated from France and Switzerland. There is growing evidence that the species is presently recolonizing these countries in the western Alps. By sequencing the mitochondrial DNA (mtDNA) control region of various samples mainly collected in the field (scats, hairs, regurgitates, blood or tissue; n = 292), we could (1) develop a non-invasive method enabling the unambiguous attribution of these samples to wolf, fox (Vulpes vulpes) or dog (Canis familiaris), among others; (2) demonstrate that Italian, French and Swiss wolves share the same mtDNA haplotype, a haplotype that has never been found in any other wolf population world-wide. Combined together, field and genetic data collected over 10 years corroborate the scenario of a natural expansion of wolves from the Italian source population. Furthermore, such a genetic approach is of conservation significance, since it has important consequences for management decisions. This first long-term report using non-invasive sampling demonstrates that long-distance dispersers are common, supporting the hypothesis that individuals may often attempt to colonize far from their native pack, even in the absence of suitable corridors across habitats characterized by intense human activities.