Woodland Caribou Rangifer Tarandus Research Articles

Simultaneous monitoring of vegetation dynamics and wildlife activity with camera traps to assess habitat change

AbstractVegetation phenology and productivity drive resource use by wildlife. Vegetation dynamics also reveal patterns of habitat disturbance and recovery. Monitoring these fine‐scale vegetation patterns over large spatiotemporal extents can be difficult, but camera traps (CTs) commonly used to survey wildlife populations also collect data on local habitat conditions. We used CTs (n = 73) from 2016 to 2019 to assess impacts of habitat change in a boreal landscape of northern Canada, where seismic lines for petroleum exploration disturbed wildlife habitat and prompted vegetation restoration efforts. First, we quantified vegetation dynamics from CTs, comparing them to satellite‐based estimates that are typically used to monitor vegetation at broad spatial scales. We then used understory phenology and productivity estimated from CT time‐lapse images to assess vegetation recovery on seismic lines. Finally, we related vegetation dynamics with the habitat use of three wildlife species: sandhill cranes Grus canadensis, woodland caribou Rangifer tarandus, and white‐tailed deer Odocoileus virginianus. CTs provided unique insight into vegetation dynamics that were different from signals measured by satellites, with temporally inconsistent and even some negative correlations between CT and satellite metrics. We found some indication of vegetation recovery on seismic lines that had received restoration treatment, with understory patterns more similar to undisturbed habitat than to seismic lines that did not receive restoration treatment. CTs also provided inferences about wildlife activity related to vegetation resources, which approaches using satellite data failed to detect. Wildlife habitat use tracked vegetation phenology, but did not always increase with vegetation productivity at weekly, 16‐day, or annual intervals. Instead, associations with vegetation productivity depended on species, temporal scale, and productivity metrics. Given the widespread and growing use of CTs to monitor terrestrial wildlife, we recommend their use to simultaneously monitor habitat conditions to better understand the mechanisms that govern wildlife habitat use in changing environments.

Quantification of Lichen Cover and Biomass Using Field Data, Airborne Laser Scanning and High Spatial Resolution Optical Data—A Case Study from a Canadian Boreal Pine Forest

Ground-dwelling macrolichens dominate the forest floor of mature upland pine stands in the boreal forest. Understanding patterns of lichen abundance, as well as environmental characteristics associated with lichen growth, is key to managing lichens as a forage resource for threatened woodland caribou (Rangifer tarandus caribou). The spectral signature of light-coloured lichen distinguishes it from green vegetation, potentially allowing for mapping of lichen abundance using multi-spectral imagery, while canopy structure measured from airborne laser scanning (ALS) of forest openings can indirectly map lichen habitat. Here, we test the use of high-resolution KOMPSAT (Korea Multi-Purpose Satellite-3) imagery (280 cm resolution) and forest structural characteristics derived from ALS to predict lichen biomass in an upland jack pine forest in Northeastern Alberta, Canada. We quantified in the field lichen abundance (cover and biomass) in mature jack pine stands across low, moderate, and high canopy cover. We then used generalized linear models to relate lichen abundance to spectral data from KOMPSAT and structural metrics from ALS. Model selection suggested that lichen abundance was best predicted by canopy cover (ALS points > 1.37 m) and to a lesser extent blue spectral data from KOMPSAT. Lichen biomass was low at plots with high canopy cover (98.96 g/m2), while almost doubling for plots with low canopy cover (186.30 g/m2). Overall the model fit predicting lichen biomass was good (R2 c = 0.35), with maps predicting lichen biomass from spectral and structural data illustrating strong spatial variations. High-resolution mapping of ground lichen can provide information on lichen abundance that can be of value for management of forage resources for woodland caribou. We suggest that this approach could be used to map lichen biomass for other regions.

Social organization of boreal woodland caribou (Rangifer tarandus caribou) in response to decreasing annual snow depth

Global climate warming is causing reductions in the depth and duration of snow cover across much of the distributional range of threatened boreal woodland caribou (Rangifer tarandus caribou). Plasticity in group size and composition among gregarious ungulates likely reflects a response to a variety of proximate factors, including environmental conditions such as snow depth. Yet, longitudinal studies of social organization by ungulates in response to environmental conditions are limited. We used 11 years of aerial survey data to examine winter group size in a northern population of boreal woodland caribou in response to late-winter snow depth. We documented caribou social organization (size and types of groups) and annual variability in group size. We tested the hypothesis that group size increases with increasing snow depth. Most groups (61%; n = 456) were ≤ 5 animals; however, they only constituted 37% of the animals. Caribou were distributed among four types of groups, including solitary females, males only, females only, and mixed groups. Group sizes differed among group types. Mixed groups were both the most common and largest groups encountered in late winter. We found a positive relationship between snow depth and group size; however, there was no relationship between snow depth and the percentage of mixed groups. These caribou may form larger groups in winters with deep snow as a behavioral strategy to reduce energetic costs, predation risk, or both. Climate-induced decreases in late-winter snow depth will likely reduce group sizes in boreal woodland caribou. However, further work is required to understand if this change in social organization will affect the persistence of local boreal woodland caribou populations.

Decision-support model to explore the feasibility of using translocation to restore a woodland caribou population in Pukaskwa National Park, Canada

The distribution and abundance of woodland caribou (Rangifer tarandus caribou) have declined dramatically in the past century. Without intervention the most southern population of caribou in eastern North America is expected to disappear within 20 years. Although translocations have reintroduced and reinforced some populations, approximately half of caribou translocation efforts fail. Translocations are resource intensive and risky, and multiple interrelated factors must be considered to assess their potential for success. Structured decision-making tools, such as Bayesian belief networks, provide objective methods to assess different wildlife management scenarios by identifying the key components and relationships in an ecosystem. They can also catalyze dialogue with stakeholders and provide a record of the complex thought processes used in reaching a decision. We developed a Bayesian belief network for a proposed translocation of woodland caribou into a national park on the northeastern coast of Lake Superior, Ontario, Canada. We tested scenarios with favourable (e.g., good physical condition of adult caribou) and unfavourable (e.g., high predator densities) conditions with low, medium, and high numbers of translocated caribou. Under the current conditions at Pukaskwa National Park, augmenting the caribou population is unlikely to recover the species unless wolf densities remain low (<5.5/1000 km2) or if more than 300 animals could be translocated.

Explaining Geographic Gradients in Winter Selection of Landscapes by Boreal Caribou with Implications under Global Changes in Eastern Canada

Many animal species exhibit broad-scale latitudinal or longitudinal gradients in their response to biotic and abiotic components of their habitat. Although knowing the underlying mechanism of these patterns can be critical to the development of sound measures for the preservation or recovery of endangered species, few studies have yet identified which processes drive the existence of geographical gradients in habitat selection. Using extensive spatial data of broad latitudinal and longitudinal extent, we tested three hypotheses that could explain the presence of geographical gradients in landscape selection of the endangered boreal woodland caribou (Rangifer tarandus caribou) during winter in Eastern Canadian boreal forests: 1) climate-driven selection, which postulates that geographic gradients are surrogates for climatic gradients; 2) road-driven selection, which proposes that boreal caribou adjust their selection for certain habitat classes as a function of proximity to roads; and 3) an additive effect of both roads and climate. Our data strongly supported road-driven selection over climate influences. Thus, direct human alteration of landscapes drives boreal caribou distribution and should likely remain so until the climate changes sufficiently from present conditions. Boreal caribou avoided logged areas two-fold more strongly than burnt areas. Limiting the spread of road networks and accounting for the uneven impact of logging compared to wildfire should therefore be integral parts of any habitat management plan and conservation measures within the range of the endangered boreal caribou. The use of hierarchical spatial models allowed us to explore the distribution of spatially-structured errors in our models, which in turn provided valuable insights for generating alternative hypotheses about processes responsible for boreal caribou distribution.

Delineation of Landcover Boundaries in Areas Utilized or Avoided by Female Woodland Caribou (Rangifer tarandus caribou) Using Publicly Available Spatial Datasets.

The availability and utility of spatial datasets, at no cost to the end user, directly impacts the ability of government and non-governmental wildlife management agencies to delineate landcover utilization or avoidance for targeted wildlife species. The availability and utility of four datasets; Canada Land Inventory for Ungulates, Earth Observation for Sustainable Development of Forests, Provincial Forest Inventory for the Island of Newfoundland, and the Landsat 7 ETM+ were evaluated for their usefulness in delineating landcover boundaries in areas utilized by caribou during calving and post-calving. To perform this evaluation a representative sample of landcover features, in both utilized and avoided areas, were selected through the use of space-time scan statistics and maximum step length calculations, then landcover boundaries were recorded using spiral transects based on the Fibonacci sequence. The location of all land cover boundaries intersected during the completion of ground based transects were recorded and provided a baseline dataset for comparison to those depicted using the selected datasets. Object-oriented segmentation had to be completed for the Landsat ETM+ dataset before a comparison could be conducted. Root mean square error (RMSE) values were calculated for all datasets and compared with the ground based results. In addition, RMSE values were also calculated for a set of randomly generated boundary locations for each completed transect. For all datasets errors of omission were taken into account on an independent basis. Upon completion of the evaluation it was determined that all datasets, except the Earth Observation for Sustainable Development of Forests, where both the RMSE for random (r) and actual (a) boundary points (r=22.89, a=14.93, error 25meters (m)) was below the associated positional error of the dataset, would be useful for the delineation of landcover boundaries. The Canada Land Inventory (r=86.60, a=30.43, error 35m) was deemed useful only for its ability to provide information on historical location and permanence of boundaries at the landscape scale. To provide landcover delineation for the island of Newfoundland a combination of both the forest inventory (r=64.71, a=39.47, error 35m) and landsat datasets (r=37.02, a=27.92, error 30m) must be utilized along with a variety of ancillary data sources.

The effect of temporal sampling regime on the characterization of home range for female boreal woodland caribou (Rangifer tarandus caribou) in Labrador, Canada

Our objective was to determine the influence of temporal sampling regime on the characteristics of individual female caribou home ranges and to explore implications of these findings to the conservation of caribou. The study population was 24 adult female caribou monitored for between 4 and 11 consecutive years between 1986 and 2009 from the Red Wine Mountain (RWM) and Lac Joseph (LJ) herds of boreal caribou in Labrador. We evaluated the influence of length of the monitoring period on the size of home ranges and fidelity of caribou to their ranges by measuring the percent overlap of multi-annual ranges on the total time period a caribou was collared and by calculating displacement between centroids of annual and multi-annual ranges for a given caribou. We found that the size of the range increased with each additional year of monitoring—initially at a rate greater than 20% per year, and then more slowly until an asymptote was reached after 7 years. The distance ratio declined with an increase in the monitoring interval until after approximately 6 years of monitoring. Finally, we evaluated trade-offs between monitoring interval and sample size by measuring the proportion of the total herd range captured by multi-annual ranges for given monitoring interval and sample size combinations. Caribou with the longest monitoring interval inevitably captured the greatest portion of the range at each given sample size. Only monitoring intervals of 4 years or greater captured more than 65% of the herd range even when sample size was doubled for shorter monitoring intervals. Our results suggest that long term monitoring is important when defining the extent of caribou ranges.

Using temporary dye marks to estimate ungulate population abundance in southwest Yukon, Canada

We describe the protocols of two mark-resight abundance surveys, using temporary dye-marks, for the Aishihik woodland caribou (Rangifer tarandus caribou) and wood bison (Bison bison athabascae) populations (herds) in the southwest Yukon Territory, Canada. We also provide recommendations based on experiences from these surveys for biologists and managers considering this approach. The Aishihik woodland caribou herd was the focus of intensive management in the 1990s aimed at recovering the herd. Following recovery activities, a target size of 2000 animals was determined and the Champagne-Aishihik Traditional Territory Community-Based Wildlife Management Plan recommended an estimate of the herd’s size be completed before the year 2013. We used an aerial mark-resight approach to estimate the herd’s size in March 2009. Caribou (n = 59) were marked from a helicopter with temporary dye, delivered via a CO2-powered rifle. Two independent resighting sessions were subsequently carried out via helicopter. The herd was estimated at 2044 animals (90% CI: 1768 – 2420) with an overall resighting rate of 0.47. The mean annual growth rate (λ) of the herd from 1997 – 2009 was 1.05 (SE = 0.01). The Aishihik wood bison herd was estimated at 1151 (90% CI: 998 – 1355). Our study suggests that ungulates temporarily marked with dye can be successfully used to obtain statistically sound population estimates.

Caribou conservation and recovery in Ontario: development and implementation of the Caribou Conservation Plan

The range of Ontario’s woodland caribou (Rangifer tarandus caribou) (forest-dwelling ecotype) has receded northward substantially over many decades, leading to its current Threatened designation. Ontario released its Caribou Conservation Plan (CCP) in the fall of 2009. This policy responded to public input and recommendations from the Ontario Woodland Caribou Recovery Team and the Caribou Science Review Panel, and outlines conservation and recovery actions to conserve and recover caribou. Within an adaptive management framework, the CCP builds upon a recent history of managing at large landscape scales in Ontario to implement a range management approach as the basis for recovery actions. These commitments and actions include enhanced research and monitoring, improved caribou habitat planning at the landscape scale, an integrated range analysis approach using advanced assessment tools to evaluate thresholds of habitat amount, arrangement and disturbance, the assessment of probability of persistence, consideration of cumulative effects, meeting forest management silvicultural performance requirements, consideration of caribou recovery implications when managing other wildlife, an initial focus on the southern edge of caribou distribution where threats are most significant, improved outreach and stewardship, and consideration of Aboriginal Traditional Knowledge in recovery actions. Implementation of the CCP signifies a long-term provincial commitment to caribou recovery, initially focusing on identified priorities within the CCP.

Implications of body condition on the unsustainable predation rates of endangered mountain caribou

Both top-down and bottom-up processes influence herbivore populations, and identifying dominant limiting factors is essential for applying effective conservation actions. Mountain caribou are an endangered ecotype of woodland caribou (Rangifer tarandus caribou) that have been declining, and unsustainable predation has been identified as the proximate cause. To investigate the role of poor nutrition, we examined the influence of sex, season, age class, and available suitable habitat (i.e., old-growth forest>140 years) per caribou on bone marrow fat content of caribou that died (n = 79). Sex was the only strong predictor of marrow fat. Males that died during and post rut had lower marrow fat than females or males at other times of year. Old-growth abundance per caribou, season, and age class did not predict marrow fat. Caribou killed by predators did not have less marrow fat than those that died in accidents, suggesting that nutritionally stressed caribou were not foraging in less secure habitats or that predators selected nutritionally stressed individuals. Marrow fat in endangered and declining populations of mountain caribou was similar to caribou in other, more viable populations. Our results support previous research suggesting that observed population declines of mountain caribou are due to excessive predation that is not linked to body condition.

Distance- versus patch-based movements of woodland caribou during spring dispersion in northern Quebec

Habitat selection studies are widespread in the scientific literature on woodland caribou (Rangifer tarandus caribou). Knowledge of habitat selection informs our understanding of caribou biology and life history requirements. Recent innovations in GPS telemetry have allowed us to track animal locations over space and time with remarkable accuracy, greatly enhancing our understanding of space use patterns and allowing us to more closely examine the role of scale and landscape heterogeneity in movements of woodland caribou. In conjunction, new spatial statistics and mechanistic approaches to resource selection analysis serve to reduce error in model selection and explain how landscape covariates influence caribou behaviour. With a view to maximizing functional connectivity between winter and summer ranges in managed landscapes of Northern Quebec, we first distinguished between biologically relevant seasonal phases in caribou movement by modeling distance moved over time using polynomial regression (Ferguson & Elkie, 2004a), identifying seasonal cut-off periods where the second derivative equals zero. We were interested in understanding how caribou per¬ ceive and respond to the heterogeneous landscape so we first tested for the presence of scalar activity in caribou move¬ ments. For each study animal (n=25) we fit a broken stick model to the ln frequency of movement rates recorded during spring dispersion, where appropriate establishing a unique rate criterion (rc) per animal (Johnson et al., 2002a) in order to differentiate between intrapatch and interpatch movements. Intrapatch movements are thought to represent forag¬ ing or resting phases whereas interpatch movements are associated with distance-based migratory activity; therefore we treated the two processes differently. We used kernel density estimates (plug-in method) for all points associated with patch-based movements during spring dispersion to define use-intensity levels for resource patches. Polytomous logistic regression was used to model patch resource selection by woodland caribou (Rittenhouse et al., 2008). In contrast, con¬ ditional logistic regression was used to model interpatch (i.e. distance-based) movements and a Step Selection Function (SSF) was built describing where a given animal was most likely to be found from one relocation to the next (Fortin et al., 2005b). Candidate models included covariates for road density, distance to forest cutovers, recent burns, terrestrial lichen abundance, coniferous forest, open wetlands, and distance to waterways. Results will be presented and application of models to connectivity analyses will be discussed.

Use of island and mainland shorelines by woodland caribou during the nursery period in two northern Ontario parks

Predation is considered a primary limiting factor of woodland caribou (Rangifer tarandus caribou) populations across North America. Caribou are especially vulnerable to predation during their first few weeks of life and have evolved space-use strategies to reduce predation risk through habitat selection during the critical calving and nursery period. We assessed landscape-scale physical characteristics and landcover types associated with caribou nursery sites in Wabakimi and Woodland Caribou Provincial Parks in northern Ontario to better understand nursery site selection in relatively undisturbed landscapes. Although free from industrial activity, these protected areas may subject caribou to human recreational disturbance, so our secondary objective was to evaluate female caribou nursery site selection relative to human recreational activities. We determined that parturient caribou selected landscape characteristics at multiple spatial scales that may reduce predation risk during the calving and nursery period. Generally, female caribou in both parks selected larger lakes with larger than average sized islands configured within shorter than average distances to other islands or landforms that might facilitate escape from predators. The majority of caribou nursery areas in both parks occurred on islands rather than the mainland shoreline of lakes that were surveyed. The nearest landform for escape from these nursery sites on islands was typically another island, and most often 2-3 islands, suggesting parturient caribou may choose islands clustered together as part of their escape strategy. In Woodland Caribou Provincial Park, caribou nursery sites occurred more often in coniferous landcover than expected from availability, while in Wabakimi Provincial Park caribou used sparse, mixed and coniferous forests for nursery activity. Caribou cow-calf pairs typically used areas for nursery activity that were 9.1 km (± 1.0 km, range 2.3-20.6 km) in Wabakimi Provincial Park and 10.2 km (± 0.7 km, range 0.7-32.6 km) in Woodland Caribou Provincial Park from any human recreational disturbance. These landscape-scale physical characteristics and landcover types associated with caribou nursery sites may be used to predict locations of potential caribou nursery areas both outside and within protected areas for the provision of adequate protection and to ensure the persistence of this valued species.

The West Central Alberta Woodland Caribou Landscape Plan: Using a Modeling Approach to Develop Alternative Scenarios

Woodland caribou (Rangifer tarandus) are classified as threatened in Alberta. In support of Canada's Species at Risk Act, a Recovery Plan for Woodland Caribou in Alberta was completed in 2004 which required local implementation plans to be completed within 5 areas of the province. The West Central Alberta Caribou Landscape Plan (WCCLP) is the first of these to be initiated and it addresses the recovery strategies for 4 herds. Two aspatial computer models built on the STELLA© modelling platform (ISee Systems, 2007) were used to assist the planning team in evaluating cumulative effects and alternative scenarios for caribou conservation. The ALCES© (Forem Technologies 2008) modelling tool was used to forecast potential changes in the west central Alberta landscape over time. Yearly landscape condition outputs from ALCES© were then exported into a caribou-specific population model, REMUS© (Weclaw, 2004), that was used to project potential population responses by woodland caribou, other primary prey species [moose (Alces alces), elk (Cervus elaphus) and deer (Odocoileus sp.)] and wolves (Canis lupus) (Weclaw & Hudson, 2004). Simulated habitat management strategies that resulted in the highest likelihood of caribou recovery included the maintenance of a high proportion of old forest, the aggregation of industrial footprints and the reclamation of historic seismic lines (although the latter took decades to provide real dividends). Sharing of industrial roads, protection of fragments of old-growth, and expanding an already aggressive fire control strategy in Alberta had little additional effect on caribou recovery. Simulated population management strategies that were successful all involved decades of intensive wolf control, either directly or indirectly through intensive primary prey control (with the exception of woodland caribou) until old-growth forests recovered to densities that provided caribou habitat and decreased alternate prey of wolves. Although this modelling approach makes broad assumptions, it provides simple fundamental relationships that were useful in a multi-stakeholder team setting when evaluating the efficacy of different management strategies for the conservation of woodland caribou.

Movements of boreal caribou in the James Bay lowlands

Little is known about the movements and home range of boreal woodland caribou (Rangifer tarandus) in the James Bay lowlands, northern Ontario. Our preliminary study involves the use of GPS collars with Argos satellite system uplink to monitor movements of caribou and 10 animals were collared in December 2004. Animals appeared to have reduced rates of daily movement starting approximately in mid to late December and stretching until late February. Similarly, most animals appeared to have very reduced rates of movement from the beginning of May to the end of June indicating that this is their calving period (includes both parturition as well as the period immediately after parturition). Thus the over-wintering range was assumed to be where the animals were from mid-December to late February and the calving range was defined as the area they were in from the beginning of May to the end of June. Individual home-ranges were typically large, the mean 90% kernel home range for 2004 - 2007 was 41 579 km2. Over wintering areas and calving areas were small when compared to annual home-range size and reflect the reduced rates of movement during these time periods. Female caribou show site fidelity to calving grounds, using the same core areas year after year. However, the same level of site fidelity was not observed in over-wintering areas. The caribou in the James Bay lowlands display behaviours that are characteristic of both the forest-tundra and forest-forest ecotypes which may warrant the reconsideration of the validity of proposed ecotypes with respect to protection under species-at-risk legislation.

Characterization of woodland caribou (Rangifer tarandus caribou) calving habitat in the boreal plains and boreal shield ecozones of Manitoba and Saskatchewan

As recovery plans are being developed or implemented for boreal caribou, it is becoming important to further examine the spatial and temporal characteristics of areas used at calving and to identify site and landscape attributes that may be selected by the animals. In order to do this, we analyzed the movement and habitat use pattern of 31 animals in the boreal plains and boreal shield ecozones. GPS telemetry data were obtained from 12 female boreal caribou from the Kississing-Naosap herd in Manitoba between 2002 and 2005, and 19 females from the Smoothstone-Wapawekka herd in Saskatchewan between 2005 and 2007. Based on movement rates, LOESS curves were used to identify eight distinct seasons for both herds. Reduced movement rates, involving a rate of 50 m/h or less for a minimum of a week, were used to identify 20 calving sites in the Smoothstone-Wapawekka herd, 13 calving sites in the Kississing-Naosap herd, and their associated preand post-calving areas. Vegetation characteristics at the site and landscape scales were examined using Forest Resource Inventory, roads, trails, fire and cutblocks data. Paired-logistic regression was used to assess calving habitat selection at the site scale and generalized estimating equations were used for the landscape scale analysis. Selection was seen to occur at the landscape scale for calving areas in both herds however, no identifiable trends were seen to occur at the site scale based on vegetation characteristics. The predictive maps of calving and potential calving habitat generated for both herds are providing key management information for the protection of boreal caribou during the calving season.

Developing a population target for an overabundant ungulate for ecosystem restoration

1. Ecosystem restoration typically focuses on re-establishing native plant communities with the hope of restoring ecological processes over the long term. In contrast, endangered species management usually focuses on short-term actions that directly affect population numbers. Here, we present an intermediate approach. We develop an ecologically based population target for the overabundant herbivore, moose Alces alces, with the goal of restoring a predator–prey system and thus preventing the extinction of the endangered ungulate, woodland caribou Rangifer tarandus. 2. Forest harvesting is a major factor contributing to increases in the number of moose, which in turn increases predator populations. Caribou populations decline as a result of increased predation representing a form of apparent competition between moose and caribou. This presents a unique conservation challenge as recovery of caribou through forest restoration would take decades, while the alternative of directly reducing predator numbers is a short-term solution. A third option is to reduce moose numbers to also maintain predators at low numbers, but the question is to what density should moose be reduced? 3. We created a statistically based target for moose abundance under conditions without forest harvesting by developing a habitat-based population model for moose under current conditions. We then calculated the habitat quality in the same area but under simulated ‘pristine’ conditions. We also evaluated three measures of ecological carrying capacity to determine the reliability of using current moose abundance to back-calculate numbers for the pristine landscape. 4. Our analysis suggests an 81·6% (71·0–89·9%, 95% CI) reduction in moose habitat quality under pristine conditions. All three measures indicated that moose numbers in the current landscape were near carrying capacity, suggesting that the current abundance could be used to approximate numbers for the pristine landscape and thus be used as an ecological target. 5. Synthesis and applications. There are few experimental tests designed to alleviate predator-mediated apparent competition by reducing overabundant prey. Our target will now be used in an adaptive management framework to evaluate the success of this recovery option for caribou, and inform whether this approach can be applied to other systems involving species endangerment from the apparent competition mechanism.

Wetland habitat selection by woodland caribou as characterized using the Alberta Wetland Inventory

We examined habitat selection by woodland caribou (Rangifer tarandus caribou) in northwestern Alberta based on a wetland classification system developed for the Alberta Vegetation Inventory. Our two objectives were to describe caribou habitat use, and to assess the utility of the wetland classification system in land-use planning on caribou range. We used a geographical information system to overlay the locations of radio-collared caribou on the habitat map. Using a "moving-window" analysis of habitat availability, we examined patterns of habitat selection by 16 individual female caribou during five seasons annually over two years. We did not detect significant differences in habitat selection patterns among seasons. Caribou showed significant preferences for both bogs and fens with low to moderate tree cover relative to marshes, uplands, heavily forested wetlands, water, and areas of human use. The wetland classification system appears to have value for broad-scale planning of industrial activity on caribou range. More-detailed descriptions of vegetation, especially understory species, are required to refine this system for operational-level forest harvest planning.

Woodland caribou calf recruitment in relation to calving/post-calving landscape composition

Since the 1990s, Newfoundland’s woodland caribou (Rangifer tarandus caribou) population has declined by an estimated 66%. Low calf recruitment has been associated to the decline, possibly triggered by increasing calf predation and/or decreasing resources. To investigate the role of landscape composition in this system, we studied the yearly (2005-2008) calving/post-calving range (CPCR) of 104 satellite-collared females belonging to six herds. We mapped nine disturbance factors (e.g. roads, logging, etc), as well as vegetation cover types (e.g. coniferous, deciduous forests, etc), and determined the total area they occupied within CPCRs yearly for each herd. Using an information theoretic approach, we assessed the model that best explained variation in recruitment using these components. Based on corrected Akaike Information Criterion, the model that best explained variation in calf recruitment included total disturbance and deciduous forest area, both showing the expected negative relationship with calf recruitment. Other landscape variables among the models with ΔAICc < 2 were mixed forest, also with a suggested negative relationship, and barrens and wetlands with a significant positive trend. This study highlights the need to minimize total disturbance footprint and account for resulting changes in forest composition within CPCRs during land use planning. Expanding forestry operations and road infrastructure in critical woodland caribou habitat across Canada may additionally contribute to habitat loss via fragmentation. This in turn, may lead to range recession beyond the initial local avoidance footprint. We see the possibility of using calf recruitment models based on landscape parameters, among others, to predict the impact of new industrial developments on calf recruitment.

Annual and monthly range fidelity of female boreal woodland caribou in respons to petroleum development

Petroleum-sector development in northern Alberta, Canada has been implicated as one factor influencing the decline of boreal woodland caribou (Rangifer tarandus caribou). Previous research showed that caribou are farther from petroleum-sector disturbances within their home range than expected. As petroleum development increases, the distance caribou can selectively place themselves relative to industrial disturbance must decrease, because distances between disturbances decrease. Conceptually, the number of local disturbances becomes so large that caribou either abandon their local avoidance behaviour or leave their traditional home range. We evaluated whether an intense petroleum- development event in northern Alberta was sufficient to result in home range abandonment by female woodland caribou. Using well locations as an index of petroleum development, we found that caribou studied from 1992 to 2000 did not change their annual or monthly range fidelity as a function of development intensity. Caribou remained in peatland complexes containing a large number of petroleum-sector disturbances rather than move to new areas, presumably because the risks of dispersing across upland habitat to reach other suitable habitat are high. Such range fidelity may have fitness consequences for woodland caribou if they suffer greater predation in areas where petroleum development is occurring.

An Analysis of Government Actions for the Protection and Recovery of Forest-dwelling Woodland Caribou (Rangifer tarandus caribou) in Ontario, Canada

The Government of Ontario has legal responsibilities to protect and recover the province’s population of forest-dwelling woodland caribou, which is classified as a threatened species. Loss and fragmentation of habitat caused by commercial timber harvesting, land clearing, and linear disturbances such as road building have resulted in range recession. Ontario’s Woodland Caribou Conservation Plan (2009) serves as the provincial government’s response to a recovery strategy. This paper contends that the likelihood of success for this conservation plan is low as it focuses on mitigating rather than eliminating threats, relies on the unproven and circumspect hypothesis that woodland caribou will re-occupy logged habitat, and lacks clarity and details on implementation. Sound government action focused on protection and recovery is needed to prevent the imperilment and extirpation of this species at risk.