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Estimation of demographic trends from vital rates provides a powerful means to estimate population trends in cryptic or difficult to study species such as woodland caribou ( Rangifer tarandus caribou (Gmelin, 1788)). Using such methods, Hervieux et al. (2013; Can. J. Zool. 92(12): 872-882) recently showed 11 of 14 woodland caribou populations in Alberta were declining at ∼8%/year following up to 18 years of monitoring. Harron (2015; Can. J. Zool. 93(2): 149-150) critiques our original study, claiming that negative biases in our demographic monitoring exaggerate our conclusions of widespread caribou declines. Here, we systematically review each of Harron's claims of bias, rejecting each of his claims upon careful review of the mechanisms by which his purported claims would manifest in our population trend estimation. Therefore, we conclude that Harron's scientific critique was superficial and misleading. Delays in conservation actions raised by Harron's critique risk diminishing opportunities to conserve and recover this federally and provincially protected species. [ABSTRACT FROM AUTHOR]

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Conservation planning for species of concern or importance can be aided by resource selection functions (RSFs) that identify important areas or attributes. Models that can be interpreted biologically and provide reasonable predictive capacity may best be based on data from individuals grouped into seasonal selection strategies for particular geographical areas or similarities in topographical and vegetative associations. We used logistic regression, the information-theoretic approach, satellite imagery, and locational data (n = 31 females; 16 803 locations) from global positioning system (GPS) collared woodland caribou (Rangifer tarandus caribou (Gmelin, 1788)) to model resource selection by animals during calving, summer, fall, breeding, winter, and late-winter seasons. Higher variation in resource use corresponded to times when caribou and their young were most susceptible to predation or when food resources were limited. Even with multiple selection strategies, caribou followed a general progression from higher to lower elevation habitats from calving and summer to late winter. Caribou selected against or completely avoided the burned-disturbed vegetation class in every season except summer. We incorporated RSFs with a raster geographic information system to create selection landscapes. We validated selection landscapes using withheld GPS data (n = 6077), 50 known calving sites, and Spearman’s rank correlation coefficient. Selection models and final selection landscapes performed well in validating use locations of woodland caribou in all seasons (all P < 0.003) and in predicting known calving sites (P < 0.001). When seasonal selection strategies are identified and models are coupled with validation, RSFs are effective tools to assist in conservation planning. La planification de la conservation des espèces préoccupantes ou importantes peut bénéficier de l’utilisation des fonction de sélection des ressources (RSF) qui identifient les sites et les caractéristiques d’intérêt. Les modèles qui se prêtent à des interprétations biologiques et qui possèdent une capacité raisonnable de prédiction peuvent idéalement se baser sur des données provenant d’individus regroupés en fonction de stratégies de sélection saisonnières dans des zones géographiques particulières ou des similarités d’associations topographiques ou végétales. Nous utilisons des régressions logistiques, une méthodologie basée sur la théorie de l’information, de l’imagerie satellitaire et des données de positionnement (n = 31 femelles; 16 803 relevés géographiques) de caribous des bois ((Rangifer tarandus caribou (Gmelin, 1788)) munis de colliers GPS (système de positionnement mondial) afin de modéliser la sélection des ressources par ces animaux durant les saisons de mise bas, d’été, d’automne, de reproduction, d’hiver et de fin d’hiver. Une variation plus élevée dans l’utilisation des ressources correspond aux périodes où les caribous et leurs petits sont le plus vulnérables à la prédation ou lorsque leurs ressources alimentaires sont limitées. Même avec des stratégies multiples de sélection, les caribous se déplacent en général progressivement des habitats de plus haute altitude vers ceux de plus basse altitude après la mise bas, en été et à l’automne. Les caribous font une sélection négative des habitats de la catégorie brûlés-perturbés ou les évitent entièrement en toute saison, sauf en été. Nous avons incorporé les RSF dans un système d’information géographique en trames afin de créer des paysages de sélection. Nous avons validé les paysages de sélection à l’aide de données GPS retenues (n = 6077), de 50 sites connus de mise bas et du coefficient de corrélation de rang de Spearman. Les modèles de sélection et les paysages de sélection finaux fonctionnement bien pour la validation du positionnement de l’utilisation des caribous en toute saison (tous les P < 0,003) et la prédiction des sites connus de mise bas (P < 0,001). Lorsque les stratégies saisonnières de sélection sont connues et que les modèles sont couplés à une validation, les RSF sont des outils efficaces pour aider à la planification de la conservation. [ABSTRACT FROM AUTHOR]

Woodland caribou (Rangifer tarandus caribou (Gmelin)) populations are in decline throughout much of their range. With increasingly rapid industrial, recreational, residential, and agricultural development of caribou habitat, tools are required to make clear, knowledgeable, and explainable management decisions to support effective conservation of caribou and their range. We developed a series of Bayesian belief networks to evaluate conservation policy scenarios applied to caribou seasonal range recovery areas. We demonstrate the utility of the networks to articulate ecological understanding among stakeholders, to clarify and explicitly depict threats to seasonal range. We also show how simulated forecasts of spatially explicit seasonal range can be compared with landscape potential with range under assumed conditions of natural disturbance. These tools have provided opportunities to operationally define and measure conditions for recovery of caribou in north-central British Columbia. [ABSTRACT FROM AUTHOR]

Linear developments such as roads, seismic lines, and pipeline rights-of-way are common anthropogenic features in the boreal forest of Alberta. These features may act as barriers to the movement of threatened woodland caribou, Rangifer tarandus caribou. Seismic lines were not barriers to caribou movements, whereas roads with moderate vehicle traffic acted as semipermeable barriers to caribou movements. Twenty-two adult female and 1 adult male woodland caribou were captured and collared on February 17–19, 1998. Each caribou was fitted with a global positioning system collar. The greatest barrier effects were evident during late winter, when caribou crossed actual roads 6 times less frequently than simulated road networks. Semipermeable barrier effects may exacerbate functional habitat loss demonstrated through avoidance behavior. Caribou may cross roads less frequently than expected for a number of reasons, including an aversion to the physical barrier presented by a road and associated forest opening, vehicle traffic, or predation by humans. The effects of habitat fragmentation through habitat loss, avoidance, and the semipermeable barrier effects of roads should be considered in developing strategies to maintain woodland caribou populations in Alberta. Roads that act as semipermeable barriers to caribou movements may make the presence of caribou more predictable in space and time, and hence compromise the "spacing out" strategy that caribou adopt to reduce predation. The approach we have outlined in this paper is a useful method to quantify the effects of human developments acting as semipermeable barriers to animal movements and should be considered in the development of animal-movement models.

The 2013 study by Hervieux et al. outlining population trends of Boreal woodland caribou ( Rangifer tarandus caribou (Gmelin, 1788)) in Alberta, Canada, utilizes statistical analysis in nonconformance with this analytical method's limitations and applied data manipulations that biases the result toward a finding of decreasing population trends. The analysis is also based on orders-of-magnitude exaggerations in the precision of field data and failed to take into account the potential for bias toward elevated annual mortality risk associated with the nonrandomized method of selection for collaring female Boreal woodland caribou, and the potential for elevated mortality as a result of the collars themselves. Due to its numerous limitations, it is unlikely that the predictive model outlined in the study is representative of actual trends in populations and is not an approach that can produce reliable population trend estimates. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Zoology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)