7 research outputs found
Whole-genome resequencing of temporally stratified samples reveals substantial loss of haplotype diversity in the highly inbred Scandinavian wolf population
Genetic drift can dramatically change allele frequencies in small populations and lead to reduced levels of genetic diversity, including loss of segregating variants. However, there is a shortage of quantitative studies of how genetic diversity changes over time in natural populations, especially on genome-wide scales. Here, we analyzed whole-genome sequences from 76 wolves of a highly inbred Scandinavian population, founded by only one female and two males, sampled over a period of 30 yr. We obtained chromosome-level haplotypes of all three founders and found that 10%-24% of their diploid genomes had become lost after about 20 yr of inbreeding (which approximately corresponds to five generations). Lost haplotypes spanned large genomic regions, as expected from the amount of recombination during this limited time period. Altogether, 160,000 SNP alleles became lost from the population, which may include adaptive variants as well as wild-type alleles masking recessively deleterious alleles. Although not sampled, we could indirectly infer that the two male founders had megabase-sized runs of homozygosity and that all three founders showed significant haplotype sharing, meaning that there were on average only 4.2 unique haplotypes in the six copies of each autosome that the founders brought into the population. This violates the assumption of unrelated founder haplotypes often made in conservation and management of endangered species. Our study provides a novel view of how whole-genome resequencing of temporally stratified samples can be used to visualize and directly quantify the consequences of genetic drift in a small inbred population
Sharing the bounty-Adjusting harvest to predator return in the Scandinavian human-wolf-bear-moose system
The increase and range extension of wolves (Canis lupus L) and brown bears ( Ursus arctos L) in Scandinavia inevitably impacts moose (Alces alces L.) populations and, as a consequence, the size and composition of the hunter harvest must be adjusted. We used a sex- and age-structured moose population model to delineate optimal harvest strategies under predation and to compare the resulting harvest composition with the strategy commonly implemented in practice. We examined how much moose density or adult sex ratio needs to change to fully compensate for losses to predation. We found a harvest allocation pattern in commonly used practical management across calves, bulls and cows that indicated a trade-off strategy between maximising the number of shot moose, the yield biomass and the number of shot prime bulls. This strategy performed quite well with respect to all yield measures and yielded an age structure most similar to the strategies maximising harvest biomass and prime bulls. Unless predation pressure was very high, the harvest loss could be completely compensated for by allowing a higher moose density. In other situations the current hunting strategy was not possible to implement and the moose density needed to sustain predation even without hunting increases dramatically. An alternative option to balance the predation loss was to accept a more female-biased sex ratio in the winter population. Hence, it may be possible to keep 50% calves in the harvest and still obtain the same total harvest if the proportion of bulls in the harvest is increased to compensate for predation. The increase of large carnivores competing with moose hunting creates conflicts and will inevitably reduce harvest yield unless hunting strategies change. We show how increased moose density and redistribution of the harvest towards bulls can mitigate this conflict and we provide a web-based tool, where stakeholders can compare the long-term effects of alternative management decisions and eventually adjust their hunting strategy accordingly. (C) 2013 Elsevier B.V. All rights reserved
Data_file_manuscript
This data file contains raw data collected at the plantation scale, within-plantation scale and the raw data from the number of pellet groups collected
Data from: Does wolf presence reduce moose browsing intensity in young forest plantations?
Large carnivores can be a key factor in shaping their ungulate preyâs behavior, which may affect lower trophic levels. While most studies on trade-offs between food acquisition and risk avoidance by ungulate prey species have been conducted in areas with limited human impact, carnivores are now increasingly returning to highly anthropogenic landscapes. Many of these landscapes are dominated by forestry, and ungulate-forestry conflicts are an increasing issue. The aim of this study was to test if the indirect effects of a re-colonizing large predator, the wolf (Canis lupus), results in a change in browsing intensity by moose (Alces alces) in young forest plantations in a boreal forest in Sweden. We selected 24 different forest plantations, with 12 located in low-wolf and 12 in high-wolf utilization areas. In each plantation, we measured browsing intensity, tree height, tree density, distance to the closest forest edge and we counted the number of moose pellet groups. In contrast to our predictions, wolf utilization was not the main driver of moose browsing patterns. Instead, moose browsing intensity declined with tree density and height. Separate analyses on the main tree species showed that wolf utilization had an influence, but browsing intensity was in fact higher in the high-wolf utilization areas for three out of five tree species. This pattern seemed to be driven by a strong confounding relationship between wolf utilization, tree density and height, which were both lower in the high-wolf utilization areas. We argue that this confounding effect is due to wolves being pushed towards the less productive parts of the landscape away from human activity centers. Therefore, we concluded that in order to better understand carnivore driven risk- mediated effects on herbivore behavior in anthropogenic landscapes we need to better understand the complexity of human-carnivore-prey-ecosystem interactions
The fear of wolves: A review of wolf attacks on humans
Summary
Because of the large scales at which large carnivores live, their conservation cannot occur only within protected areas. They must therefore be conserved within multi-use landscapes where conflicts with humans occur. Conflicts are diverse and include depredation on livestock and competition for wild ungulates. However, one of the most serious is the fear of being injured or killed by a large carnivore. Man-killing by tigers, lions, leopards, pumas and bears (brown bear, black bear, polar bear and sloth bear) occurs on a regular basis with hundreds of people being killed annually on a worldwide basis. Although the danger that wolves pose to human safety remains controversial, may people that live in wold range report that they are afraid of wolves. This report attempts to examine the existing data about wolf attacks on humans during the last few hundred years around the world
The fear of wolves: A review of wolf attacks on humans
Summary
Because of the large scales at which large carnivores live, their conservation cannot occur only within protected areas. They must therefore be conserved within multi-use landscapes where conflicts with humans occur. Conflicts are diverse and include depredation on livestock and competition for wild ungulates. However, one of the most serious is the fear of being injured or killed by a large carnivore. Man-killing by tigers, lions, leopards, pumas and bears (brown bear, black bear, polar bear and sloth bear) occurs on a regular basis with hundreds of people being killed annually on a worldwide basis. Although the danger that wolves pose to human safety remains controversial, may people that live in wold range report that they are afraid of wolves. This report attempts to examine the existing data about wolf attacks on humans during the last few hundred years around the world
The role of human-related risk in breeding site selection by wolves
Large carnivores can be found in different scenarios of cohabitation with humans. Behavioral adaptations to minimize risk from humans are expected to be exacerbated where large carnivores are most vulnerable, such as at breeding sites. Using wolves as a model species, along with data from 26 study areas across the species' worldwide range, we performed a meta-analysis to assess the role of humans in breeding site selection by a large carnivore. Some of the patterns previously observed at the local scale become extrapolatable to the entire species range provided that important sources of variation are taken into account. Generally, wolves minimised the risk of exposure at breeding sites by avoiding human-made structures, selecting shelter from vegetation and avoiding agricultural lands. Our results suggest a scaled hierarchical habitat selection process across selection orders by which wolves compensate higher exposure risk to humans within their territories via a stronger selection at breeding sites. Dissimilar patterns between continents suggest that adaptations to cope with human-associated risks are modulated by the history of coexistence and persecution. Although many large carnivores persisting in human-dominated landscapes do not require large-scale habitat preservation, habitat selection at levels below occupancy and territory should be regarded in management and conservation strategies aiming to preserve these species in such contexts. In this case, we recommend providing shelter from human interference at least in small portions of land in order to fulfill the requirements of the species to locate their breeding sites.We are in debt with all the administrative, logistical and funding support from the Picos de Europa National Park and the Regional Government of Galicia (Spain), the Spanish Ministry of Economy and Competitiveness (SEV-2012-0262), the Government of the Northwest Territories and the University of Northern British Columbia (Canada), the U.S.A. National Park Service, the Alaska Department of Fish and Game, the U.S.A. Department of Agriculture (USDA) Forest Service, the Wisconsin Departments of Natural Resources and Transportation, the University of Wisconsin-Stevens Point, the Government of India, the Regional Government of Maharastra (India), the Progetto Lupo Piemonte (Italy), the European Union, the Slovenian Ministry of Agriculture and Environment (LIFE08/NAT/SLO/000244), and the Mexican Wolf Recovery Program (partnership: USFWS, AGFD, WMAT, USDA Forest Service, and the USDA Animal and Plant Health Inspection ServicesâWildlife Services, and several participating counties). JVLB was supported by the Spanish Ministry of Economy and Competitiveness (JCI-2012-13066). MK was supported by Slovenian Research Agency (ARRS, P4-0059)