In Alberta, Canada (1982, and in Idaho, Montana, and Wyoming, United States (1987-2001), wolves ( Canis lupus) killed various domestic animals, among which the major prey were sheep in the United States (68%, n = 494) and cattle in Canada (95%; n = 1633). Under recovery programs, the wolf population increased in the United States, and depredation events increased proportionately. In both countries, the number of domestic animals killed each year was correlated with the number of wolves killed by government authorities for depredation management. We tested the ability of antiwolf barriers made of flags hanging from ropes to impede wolf access to food and livestock. In 18 experiments, barriers prevented captive wolves (n = 9) from accessing food for up to 28 hours and allowed daily separation of wolves to administer contraceptive pills to a female wolf. Barriers prevented access by wild wolves to 100-m 2 baited sites during two 60-day tests. We also set barriers around three cattle pastures. In Alberta during two 60-day trials on 25-ha pastures, wolves approached barriers on 23 occasions but did not cross them, and no cattle were killed. Wolves killed cattle on neighboring ranches during the trials and before and after the trials on the tested ranches. In Idaho four radiocollared wolves crossed barriers and killed cattle in a 400-ha ranch after 61 days of barrier exposure. Our results suggest that antiwolf barriers are effective in deterring captive and wild wolves for >1 and ≥60 days, respectively, and that wild wolves switch to alternative livestock when excluded from one herd of livestock. Our depredation data indicate that protecting livestock from wolves reduces the necessity for killing wolves. Barriers could play a role among the limited set of preventive measures available and offer a cost-effective mitigation tool for the problem of livestock depredation on a local scale.Tendencias en la Depredación por Lobos y el Uso de Barreras para Proteger Ganado en Norte América Occidental Resumen: En Alberta, Canadá (1982 a 2001) y en Idaho, Montana y Wyoming, Estados Unidos (1987 a 2001), los lobos ( Canis lupus) mataron a varios animales domésticos en su mayoría ovejas ovejas en EstadosUnidos (68%, n = 494), y ganado vacuno en Canadá (95%; n = 1633). La población de lobos incrementó en Estados Unidos bajo programas de recuperación y los casos de depredación incrementaron proporcionalmente. En ambos países, el número de animales domésticos depredados cada año se correlacionó con el número de lobos matados por autoridades gubernamentales para la gestión de la depredación. Probamos la efectividad de barreras contra lobos hechas de banderas colgando de cuerdas para impedir el acceso de lobos § §email mmusiani@ucalgary.ca Musiani et al. Wolf Depredation and Fladry Barriers 1539a alimento y ganado. En 18 experimentos, las barreras previnieron que los lobos cautivos (n = 9) accedieran al alimento por hasta 28 horas y permitieron la separación diaria de los lobos para administrar píldoras anticonceptivas a una hembra. Las ...

Due primarily to wolf (Canis lupus) predation on livestock (depredation), some livestock producers and other interest groups oppose wolf conservation, which is an important objective for large sectors of the public. Predicting depredation occurrence is difficult, yet necessary to prevent it. Better prediction of wolf depredation also would facilitate application of sound depredation management actions. In this paper we analyze temporal trends in wolf depredation occurrence and wolf control, which is employed as a depredation management action. We gathered data from wolf depredation investigations for Alberta, Canada, from 1982–1996 and for Idaho, Montana, and Wyoming, USA, from 1987–2003. We showed that wolf attacks occurred with a seasonal pattern, reflecting the seasonality of livestock calving, grazing practices, and seasonal variation in energetic requirements of wolf packs. Seasonal wolf attacks were auto‐correlated with lags of one year, indicating annual reoccurrence. Cross‐correlation analyses indicated that limited wolf control was rapidly employed as a short‐term response to depredation, and was not designed to decrease wolf depredation at a regional scale or in the long‐term. We therefore discovered a reoccurring seasonal‐annual pattern for wolf depredation and wolf control in western North America. Ranchers and managers could use our data for focusing investment of resources to prevent wolf depredation increases during high‐depredation seasons.

Agricultural land in Canada comprises cultivated land, hayland and grazing land with associated riparian areas, wetlands, woodlands, and natural grasslands. Although these agro-ecosystems support many species of Canada’s native fauna, agricultural land use is dynamic, and changes in agricultural practices can have important implications for biodiversity. We report on Agriculture and Agri-Food Canada’s National Agri-environmental Health Analysis and Reporting Program’s assessment of wildlife habitat on farmland in Canada. Habitat use matrices were developed for 493 species of birds, mammals, reptiles and amphibians associated with farm land habitat in Canada. We derived patterns of land use from Statistics Canada’s Census of Agriculture data and applied them at the soil landscape polygon scale. We developed a proportionally weighted Habitat Capacity index to relate habitat use and land use. A 5% decrease in Habitat Capacity occurred on Canada’s agricultural land from 1981 to 2001, associated with an expansion in cropland and a decline in pasture. A regional pattern of small decline in Habitat Capacity is evident in the Prairie Provinces, where dramatic declines in the use of summerfallow had a positive impact on Habitat Capacity. In eastern Canada, greater decreases in Habitat Capacity occurred, associated with an increase in agricultural intensification. Policies and programs designed to sustain biodiversity should not be developed independently of socioeconomic factors or policies favouring agricultural intensification. We recommend a holistic approach to making policy decisions relevant to environmental and economic sustainability in the Canadian agricultural landscape. Key words: Biodiversity, land use change, agroecosystems, wildlife habitat, indicators

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