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Industrial forestry activities can increase landscape fragmentation, impacting wildlife populations, particularly Canada's woodland caribou, Rangifer tarandus caribou. To protect caribou in areas with forestry activities, the province of Ontario, Canada, implemented a Dynamic Caribou Harvest Schedule (DCHS). The DCHS spatially aggregates harvest disturbance into regions and distributes them across the landscape to maintain forest patch size–age distributions consistent with a natural variation range. However, the DCHS may negatively impact the cost of timber supply. We compared the DCHS with an alternative zoning approach that assigned the harvest deferral and operational management zones within a large forest area. We compared these approaches using an optimization model that combined harvest scheduling, access road construction, and caribou protection sub-problems. We formulated the protection of caribou habitat and road construction as network flow problems, while the harvesting problem incorporated the ecological constraints prescribed by the forest management plan. We compared the DCHS and zoning approaches in the Wabadowgang Noopming Forest of Ontario, a boreal area within the caribou distribution zone. For the same volume of sustainable harvest, the zoning approach protected less total area but more habitat and old-growth stands over the long term, and yielded lower timber costs by 1.2–2.2 $·m−3 than the DCHS. [ABSTRACT FROM AUTHOR]

Adult female survival and calf recruitment influence population dynamics, but there is limited information on calving and neonatal mortality of boreal woodland caribou (Rangifer tarandus caribou; caribou) in Ontario, Canada. We identified calf parturition sites and 5‐week neonatal mortality using a movement‐based approach across 3 northern Ontario study regions (Pickle Lake, Nakina, and Cochrane) that vary in their capacity to support caribou populations. In comparing 22 caribou‐years of video‐collar footage during 2010–2013 to predictions of the movement‐based approach, we found live parturition events were 100% correctly classified, date of parturition was within 1.08 ± 0.28 (x¯ ± SE) days, and mortality events up to 5 weeks postpartum were 88% correctly classified. Across study regions, 87% of 186 caribou were pregnant and 76% of 107 caribou‐years indicated birth events with median parturition dates a week later in Cochrane (23 May) than in Pickle Lake (17 May) and Nakina (16 May). Based on selection ratios of caribou‐years with calves‐at‐heel (n = 80), caribou consistently selected for lowlands and closed‐canopied forests and mostly against early‐seral stands (<20 yrs old) and areas near linear features during the neonatal and the post‐neonatal period (up to 35 days postpartum). Based on the video footage and movement models, 30% of 81 caribou‐years that indicated live births also showed females lost their calf within the first 5 weeks postpartum, with higher risk of neonatal mortality associated with increased use of lowlands and greater postpartum movement rates. This study provides informative metrics of caribou reproduction across northern Ontario that will contribute to future population modeling and identifies important landscape features to be considered in future industrial development and land use planning for caribou conservation. © 2020 The Wildlife Society. Parturition and neonatal mortality rates can be predicted accurately from movement rates. Caribou selected calving (neonatal and post‐neonatal) areas to minimize predation risk, but greater use of lowlands and increased movement rates postpartum increased risk of neonatal mortality. [ABSTRACT FROM AUTHOR]

One of the most challenging tasks in wildlife conservation and management is to clarify how spatial variation in land cover due to anthropogenic disturbance influences wildlife demography and long‐term viability. To evaluate this, we compared rates of survival and population growth by woodland caribou (Rangifer tarandus caribou) from 2 study sites in northern Ontario, Canada that differed in the degree of anthropogenic disturbance because of commercial logging and road development, resulting in differences in predation risk due to gray wolves (Canis lupus). We used an individual‐based model for population viability analysis (PVA) that incorporated adaptive patterns of caribou movement in relation to predation risk and food availability to predict stochastic variation in rates of caribou survival. Field estimates of annual survival rates for adult female caribou in the unlogged (x¯= 0.90) and logged (x¯= 0.76) study sites recorded during 2010–2014 did not differ significantly (P > 0.05) from values predicted by the individual‐based PVA model (unlogged: x¯ = 0.87; logged: x¯= 0.79). Outcomes from the individual‐based PVA model and a simpler stage‐structured matrix model suggest that substantial differences in adult survival largely due to wolf predation are likely to lead to long‐term decline of woodland caribou in the commercially logged landscape, whereas the unlogged landscape should be considerably more capable of sustaining caribou. Estimates of population growth rates (λ) for the 2010–2014 period differed little between the matrix model and the individual‐based PVA model for the unlogged (matrix model x¯ = 1.01; individual‐based model x¯ = 0.98) and logged landscape (matrix model x¯ = 0.88; individual‐based model x¯ = 0.89). We applied the spatially explicit PVA model to assess the viability of woodland caribou across 14 woodland caribou ranges in Ontario. Outcomes of these simulations suggest that woodland caribou ranges that have experienced significant levels of commercial forestry activities in the past had annual growth rates <0.89, whereas caribou ranges that had not experienced commercial forestry operations had population growth rates >0.96. These differences were strongly related to regional variation in wolf densities. Our results suggest that increased wolf predation risk due to anthropogenic disturbance is of sufficient magnitude to cause appreciable risk of population decline in woodland caribou in Ontario. © 2020 The Authors. The Journal of Wildlife Management published by Wiley Periodicals, Inc. on behalf of The Wildlife Society. We used matrix and individual‐based population viability assessment models to compare the demography of woodland caribou populations in Ontario in unlogged landscapes with those in logged landscapes. Our results suggest that increased wolf predation risk due to anthropogenic disturbance is of sufficient magnitude to cause appreciable risk of population decline in woodland caribou in Ontario. [ABSTRACT FROM AUTHOR]

Aim An understanding of the factors that influence species distributions in heterogeneous landscapes is important when making decisions regarding conservation. Moreover, occupancy probabilities based on detection data can reveal important species-habitat relationships. Accounting for the spatial autocorrelation of detection data increases the statistical validity of occupancy models, but is not often considered. Using novel occupancy modelling that explicitly incorporates detectability and spatial autocorrelation, we assessed the influence of habitat on occupancy patterns of woodland caribou ( Rangifer tarandus caribou), moose ( Alces alces) and wolves ( Canis lupus) across a broad biogeographical extent where fire is the dominant agent of disturbance. Location Northern Ontario, Canada. Methods We aerially surveyed 3851 sampling units, each covering 100 km2, for woodland caribou, moose and wolves in February-March in 2009, 2010 and 2011, and visited 1663 units more than once to estimate detectability. We used restricted spatial regression to model occupancy probabilities of each species with respect to habitat factors in two ecozones, accounting for both imperfect detection and lack of independence of sampling units. Results Covariates influencing species detection varied among ecozones and species. Caribou occupancy was positively related to bogs and negatively related to disturbed areas, while moose occupancy showed opposite responses to these covariates. Wolf occupancy was related to high prey occupancy. Explicitly accounting for spatial autocorrelation in detection data reduced the chance of type I error in occupancy estimates compared with non-spatial models. Main conclusions Habitat relationships and occupancy patterns support the hypothesis that caribou remain spatially segregated from moose to reduce predation risk. The broad scale of analysis indicated changes in species-habitat relationships, suggesting that limiting factors vary across biogeographical gradients. The spatial pattern in caribou occupancy allowed us to identify important areas used by caribou across the region, including the ecotone between fire-driven boreal forests and peatland complexes. The evidence for significant relationships between caribou and land cover, predators and alternate prey underscores the need for careful planning of development and infrastructure in the area. [ABSTRACT FROM AUTHOR]

The article discusses research by biologists John Fryxell, Jim Baker, and team into the decline of woodland caribou (Rangifer tarandus caribou) in Ontario, Canada using population viability analysis (PVA) to identify potential causes and conservation remedies. Two ecotypes of Ontario caribou are described, one that migrates between tundra and boreal forest and one which remains in the boreal forest in every season. The caribou habitat has been altered by deforestation from logging and mining, as well as changes in forest composition caused by global warming. The PVA looked at factors such as increased competition between caribou and moose and predation by wolves as the species are driven into new habitats, parasitism by black flies, and caribou feeding on mosses and lichens.

Although still posing challenges, science-based knowledge (including interdisciplinary work) is leading current forest-management planning. How then can indigenous communities mobilize their own knowledge to support their desire to develop new ways of managing the forest? In northern Ontario, the provincial government has developed a cross-scale planning approach that allocates certain responsibilities to First Nations in order to support their vision and knowledge, yet at the same time addresses provincial planning goals. Within this context, research on woodland caribou (Rangifer tarandus) was conducted in collaboration with Pikangikum First Nation to support their participation in forest-management planning. The outcomes of this research are used as a focal point for discussing some of the stressors that influence cross-scale planning for forestry in northern Ontario. The paper concludes that resolving cultural differences in a forest-management planning context is not entirely necessary to move forward with collaborative planning for the conservation of woodland caribou habitat. [ABSTRACT FROM AUTHOR]

The decline of woodland caribou (Rangifer tarandus caribou) has been attributed to anthropogenic landscape disturbances, but critical distance thresholds and time lags between disturbance and extirpation are unknown. Using a database of caribou presence and extirpation for northern Ontario, Canada, geo-coded to 10 X 10-km cells, we constructed logistic regression models to predict caribou extirpation based on distance to the nearest of each of 9 disturbance types: forest cutovers, fires, roads, utility corridors, mines, pits and quarries, lakes, trails, and rail lines. We used Akaike's Information Criterion to select parsimonious models and Receiver-Operating Characteristic curves to derive optimal thresholds. To deal with the effects of spatial autocorrelation on estimates of model significance, we used subsampling and restricted randomizations. Forest cutovers were the best predictor of caribou occupancy, with a tolerance threshold of 13 km to nearest cutover and a time lag of 2 decades between disturbance by cutting and caribou extirpation. Management of woodland caribou should incorporate buffers around habitat and requires long-term monitoring of range occupancy. [ABSTRACT FROM AUTHOR]