Determining Sustainable Levels of Cumulative Effects for Boreal Caribou

Abstract

: Direct and indirect effects of industrial development have contributed, in part, to the threatened status of boreal ecotype caribou (Rangifer tarandus caribou) in Alberta and Canada. Our goal was to develop a model that would allow managers to identify landscape‐scale targets for industrial development, while ensuring functional habitat for sustainable caribou populations. We examined the relationship between functional habitat loss resulting from cumulative effects of natural and anthropogenic disturbance, and the rate of population change (Λ) for 6 populations of boreal caribou in Alberta, Canada. We defined functional habitat loss according to 2 variables for which we had a priori reasons to suspect causative associations with Λ: 1) percentage area of caribou range within 250 m of anthropogenic footprint, and 2) percentage of caribou range disturbed by wildfire within the last 50 years. Multiple regression coefficients for both independent variables indicated significant effects on Λ. The 2‐predictor model explained 96% (R2) of observed variation in Λ among population units (F2,3 = 35.2, P = 0.008). The model may be used to evaluate plans for industrial development in relation to predicted wildfire rates and goals for caribou population growth rates.

Learning from the past to predict the future: using archaeological findings and GPS data to quantify reindeer sensitivity to anthropogenic disturbance in Norway

“…On the contrary, wild reindeer and caribou are well known for decreasing their foraging time and fleeing in response to hikers approaching on flooded due to the construction of a dam: while in such cases the probability of area use is likely close to zero, if the dam was constructed on a marginal part of the surrounding area P(use) can be much higher. In accordance to previous studies, the cumulative effects of the piecemeal development of infrastructures associated to dams can have significant effects on reindeer space use (Nellemann et al 2003;Sorensen et al 2008).…”

“…Notwithstanding the rapidly increasing amount of studies on the effects of anthropogenic disturbance, a comprehensive approach to quantify wild species' spatial responses to different types of infrastructures has not yet been developed. Research focus has shifted from early studies documenting short-term behavioural or physiological reactions towards more comprehensive long-term approaches investigating the species' changes in space 55 use at the landscape scale (Underhill and Angold 2000), ultimately aiming at linking individual responses to population processes (Mallord et al 2007;Gaillard et al 2010;Sorensen et al 2008). The most recent studies investigate disturbance effects by measuring to which extent anthropogenic factors influence habitat selection (Johnson et al 2005;Aarts et al 2008;Polfus et al 2011).…”

Historical changes in caribou distribution and land cover in and around Prince Albert National Park: land management implications

“…When applying their equation to the PAGE area, we obtained a X of 1.06 when the amount of disturbance was calculated as a proportion of the entire PAGE study area, 1.03 when based on a study area excluding PANP and 1.17 when based on the extent of caribou home ranges (Arsenault & Manseau, 2011). This suggests that the amount of disturbance in the PAGE is below the disturbance threshold iden¬ tified by Sorensen et al (2007) and the area should support a stable or growing population. Population demographic work done by Rettie & Messier (1998) for the period of 1992-1995 and the PAGE study for 2004(Arsenault & Manseau, 2011 do not sup¬ port these results.…”

“…A developed roads and trails network may also facilitate access to formerly isolated areas increasing mortality, from hunting and preda¬ tion (Dyer et al, 2001;Whittington et al, 2005) and from caribou-vehicle accidents (Cumming & Beange, 1987). In an attempt to identify landscape distur¬ bance threshold for woodland caribou, Sorensen et al (2007) examined the relationship between functional habitat loss resulting from cumulative effects of natural and anthropogenic disturbances, and the rate of population change for six populations of boreal caribou in Alberta, Canada. In defining habitat loss as the percentage area of caribou range within 250 m of anthropogenic footprint and the percentage of caribou range disturbed by wildfire within the last 50 years, they obtained a strong negative cor¬ relation between these two variables and population growth rate.…”

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

“…This information is used, for example, to ensure harvest is sustainable (Saether et al, 2001), to establish baseline conditions prior to anthropogenic activities on the landscape, and to subsequently assess the impacts of these activities (Sorensen et al, 2008). Furthermore, abundance estimates can be used to obtain a greater understanding of ecological processes influencing a single population's (e.g., Jenkins & Barten, 2005) or multiple populations' dynamics (e.g., Vors & Boyce, 2009;Wittmer et al, 2010).…”