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Stan Boutin - One of the best experts on this subject based on the ideXlab platform.
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Habitat loss accelerates for the endangered woodland Caribou in western Canada
'Wiley', 2021Co-Authors: Mariana Nagy‐reis, Mark Hebblewhite, Dave Hervieux, Melanie Dickie, Anna M. Calvert, Dale R. Seip, Sophie L. Gilbert, Oscar Venter, Craig Demars, Stan BoutinAbstract:Abstract Habitat loss is often the ultimate cause of species endangerment and is also a leading factor inhibiting species recovery. For this reason, species‐at‐risk legislation, policies and plans typically focus on habitat conservation and restoration as mechanisms for recovery. To assess the effectiveness of these instruments in decelerating habitat loss, we evaluated spatiotemporal habitat changes for an iconic endangered species, woodland Caribou (Rangifer Tarandus Caribou). We quantified changes in forest cover, a key proxy of Caribou habitat, for all Caribou subpopulations in Alberta and British Columbia, Canada. Despite efforts under federal and provincial recovery plans, and requirements listed under Canada's Species at Risk Act, Caribou subpopulations lost twice as much habitat as they gained during a 12‐year period (2000–2012). Drivers of habitat loss varied by ecotype, with Boreal and Northern Mountain Caribou affected most by forest fire and Southern Mountain Caribou affected more by forest harvest. Our case study emphasizes critical gaps between recovery planning and habitat management actions, which are a core expectation under most species‐at‐risk legislation. Loss of Caribou habitat from 2000 to 2018 has accelerated. Linear features within Caribou ranges have also increased over time, particularly seismic lines within Boreal Caribou ranges, and we estimated that only 5% of seismic lines have functionally regenerated. Our findings support the idea that short‐term recovery actions such as predator reductions and translocations will likely just delay Caribou extinction in the absence of well‐considered habitat management. Given the magnitude of ongoing habitat change, it is clear that unless the cumulative impacts of land‐uses are effectively addressed through planning and management actions that consider anthropogenic and natural disturbances, we will fail to achieve self‐sustaining woodland Caribou populations across much of North America
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comparison of pre fire and post fire space use reveals varied responses by woodland Caribou Rangifer Tarandus Caribou in the boreal shield
Canadian Journal of Zoology, 2020Co-Authors: Joseph Silva, Arthur R Rodgers, Scott E Nielsen, Philip D Mcloughlin, C Hague, Stan BoutinAbstract:By regulating successional dynamics in Canada’s boreal forest, fires can affect the distribution of the Threatened woodland Caribou (Rangifer Tarandus Caribou (Gmelin, 1788)). Caribou tend to avoid...
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managing wolves canis lupus to recover threatened woodland Caribou Rangifer Tarandus Caribou in alberta
Canadian Journal of Zoology, 2014Co-Authors: Dave Hervieux, Mark Hebblewhite, Dave Stepnisky, Michelle Bacon, Stan BoutinAbstract:Across Canada, woodland Caribou (Rangifer Tarandus Caribou (Gmelin, 1788)) populations are declining because of human-induced changes to food webs that are resulting in apparent competition-induced increases in predator-caused Caribou mortality. We tested the hypothesis that wolf (Canis lupus L., 1758) population reduction could reverse declines in a woodland Caribou population following a BACI (before-after-control-impact) design conducted over a 12-year period in west-central Alberta, Canada. We monitored annual survival for 172 adult female Caribou and calf recruitment from 2000 through 2012 and conducted a provincial government delivered wolf population reduction program annually during the winters of 2005-2006 to 2012 (inclusive) in an area centered on the Little Smoky range. Wolf removal translated to a 4.6% increase in mean population growth rate of the Little Smoky population mostly through improvements in calf recruitment. In contrast, the Red Rock Prairie Creek control population exhibited a 4.7% decline. Although the wolf population reduction program appeared to stabilize the Little Smoky population, it did not lead to population increase, however, with remaining approximately equal to 1. Therefore, we recommend, if required, predation management be combined with effective habitat conservation and long-term planning to effect the recovery of species, such as woodland Caribou, which are declining as a result of habitat-mediated apparent competition.
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black bear use of seismic lines in northern canada
Journal of Wildlife Management, 2014Co-Authors: Jesse Tigner, Erin M Bayne, Stan BoutinAbstract:The development of hydrocarbon resources in northwestern Canada has resulted in a vast network of seismic lines. Seismic lines are a conservation concern because they are believed to alter the use of space by predators and ultimately change predator-prey relationships. Such changes are believed to be a key factor influencing declines in boreal woodland Caribou (Rangifer Tarandus Caribou). Using remote wildlife cameras, we measured the behavioral response of a known Caribou predator, the black bear (Ursus americanus), to seismic lines at 2 spatial scales. At the line scale, we compared black bear use of lines that varied in width and vegetation recovery state to undisturbed forest interior locations. At a 5-km2 scale, we compared the probability of bear use across a continuum of seismic line density. At both spatial scales, we also tested for an interaction between bear use of seismic lines and use of upland and lowland forest types. Black bears used most types of seismic lines more frequently than undisturbed forest interior and upland forest more than lowland forest. We found no evidence of an interaction between lines and forest type, as the relative difference in seismic line versus forest interior use was the same in lowland and upland forest. At the 5-km2 scale, we found no evidence of increased use of lowland forest in areas with greater seismic line density. Thus, seismic lines did not appear to increase black bear use of lowland forest types per se. However, bears used seismic lines more than forest interiors, which might alter their ability to locate and capture Caribou and other ungulate prey, thereby creating the potential for altered predator-prey dynamics in landscapes with seismic lines. Bears do not appear to use seismic lines ≤2 m wide more often than the forest interior. We suggest that where new seismic lines are constructed, those seismic lines should be a maximum width of 2 m to reduce the potential for altered predator-prey dynamics in areas being developed for oil and gas extraction. © 2014 The Wildlife Society.
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wolves white tailed deer and beaver implications of seasonal prey switching for woodland Caribou declines
Ecography, 2013Co-Authors: David A M Latham, Cecilia M Latham, Mark Hebblewhite, Kyle H Knopff, Stan BoutinAbstract:Population increases of primary prey can negatively impact alternate prey populations via demographic and behavioural responses of a shared predator through apparent competition. Seasonal variation in prey selection patterns by predators also can aff ect secondary and incidental prey by reducing spatial separation. Global warming and landscape changes in Alberta ’ s bitumen sands have resulted in prey enrichment, which is changing the large mammal predator – prey system and causing declines in woodland Caribou Rangifer Tarandus Caribou populations. We assessed seasonal patterns of prey use and spatial selection by wolves Canis lupus in two woodland Caribou ranges in northeastern Alberta, Canada, that have undergone prey enrichment following recent white-tailed deer Odocoileus virginianus invasion. We determined whether risk of predation for Caribou (incidental prey) and the proportion of wolf-caused-Caribou mortalities varied with season. We found that wolves showed seasonal variation in primary prey use, with deer and beaver Castor canadensis being the most common prey items in wolf diet in winter and summer, respectively. Th ese seasonal dietary patterns were refl ected in seasonal wolf spatial resource selection and resulted in contrasting spatial relationships between wolves and Caribou. During winter, wolf selection for areas used by deer maintained strong spatial separation between wolves and Caribou, whereas wolf selection for areas used by beaver in summer increased the overlap with Caribou. Changing patterns in wolf resource selection were refl ected by Caribou mortality patterns, with 76.2% of 42 adult female Caribou mortalities occurring in summer. Understanding seasonal patterns of predation following prey enrichment in a multiprey system is essential when assessing the eff ect of predation on an incidental prey species. Our results support the conclusion that wolves are proximately responsible for woodland Caribou population declines throughout much of their range.
Mark Hebblewhite - One of the best experts on this subject based on the ideXlab platform.
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Habitat loss accelerates for the endangered woodland Caribou in western Canada
'Wiley', 2021Co-Authors: Mariana Nagy‐reis, Mark Hebblewhite, Dave Hervieux, Melanie Dickie, Anna M. Calvert, Dale R. Seip, Sophie L. Gilbert, Oscar Venter, Craig Demars, Stan BoutinAbstract:Abstract Habitat loss is often the ultimate cause of species endangerment and is also a leading factor inhibiting species recovery. For this reason, species‐at‐risk legislation, policies and plans typically focus on habitat conservation and restoration as mechanisms for recovery. To assess the effectiveness of these instruments in decelerating habitat loss, we evaluated spatiotemporal habitat changes for an iconic endangered species, woodland Caribou (Rangifer Tarandus Caribou). We quantified changes in forest cover, a key proxy of Caribou habitat, for all Caribou subpopulations in Alberta and British Columbia, Canada. Despite efforts under federal and provincial recovery plans, and requirements listed under Canada's Species at Risk Act, Caribou subpopulations lost twice as much habitat as they gained during a 12‐year period (2000–2012). Drivers of habitat loss varied by ecotype, with Boreal and Northern Mountain Caribou affected most by forest fire and Southern Mountain Caribou affected more by forest harvest. Our case study emphasizes critical gaps between recovery planning and habitat management actions, which are a core expectation under most species‐at‐risk legislation. Loss of Caribou habitat from 2000 to 2018 has accelerated. Linear features within Caribou ranges have also increased over time, particularly seismic lines within Boreal Caribou ranges, and we estimated that only 5% of seismic lines have functionally regenerated. Our findings support the idea that short‐term recovery actions such as predator reductions and translocations will likely just delay Caribou extinction in the absence of well‐considered habitat management. Given the magnitude of ongoing habitat change, it is clear that unless the cumulative impacts of land‐uses are effectively addressed through planning and management actions that consider anthropogenic and natural disturbances, we will fail to achieve self‐sustaining woodland Caribou populations across much of North America
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natural regeneration on seismic lines influences movement behaviour of wolves and grizzly bears
PLOS ONE, 2018Co-Authors: Laura Finnegan, Jerome Cranston, Lalenia Neufeld, Fiona Schmiegelow, Karine E. Pigeon, Mark Hebblewhite, Julie Duval, Marco Musiani, Gordon B. StenhouseAbstract:Across the boreal forest of Canada, habitat disturbance is the ultimate cause of Caribou (Rangifer Tarandus Caribou) declines. Habitat restoration is a focus of Caribou recovery efforts, with a goal to finding ways to reduce predator use of disturbances, and Caribou-predator encounters. One of the most pervasive disturbances within Caribou ranges in Alberta, Canada are seismic lines cleared for energy exploration. Seismic lines facilitate predator movement, and although vegetation on some seismic lines is regenerating, it remains unknown whether vegetation regrowth is sufficient to alter predator response. We used Light Detection and Ranging (LiDAR) data, and GPS locations, to understand how vegetation and other attributes of seismic lines influence movements of two predators, wolves (Canis lupus) and grizzly bears (Ursus arctos). During winter, wolves moved towards seismic lines regardless of vegetation height, while during spring wolves moved towards seismic lines with higher vegetation. During summer, wolves moved towards seismic lines with lower vegetation and also moved faster near seismic lines with vegetation <0.7 m. Seismic lines with lower vegetation height were preferred by grizzly bears during spring and summer, but there was no relationship between vegetation height and grizzly bear movement rates. These results suggest that wolves use seismic lines for travel during summer, but during winter wolf movements relative to seismic lines could be influenced by factors additional to movement efficiency; potentially enhanced access to areas frequented by ungulate prey. Grizzly bears may be using seismic lines for movement, but could also be using seismic lines as a source of vegetative food or ungulate prey. To reduce wolf movement rate, restoration could focus on seismic lines with vegetation <1 m in height. However our results revealed that seismic lines continue to influence wolf movement behaviour decades after they were built, and even at later stages of regeneration. Therefore it remains unknown at what stage of natural regeneration, if any, wolves cease to respond to seismic lines. To reduce wolf response to seismic lines, active restoration tactics like blocking seismic lines and tree planting, along with management of alternate prey, could be evaluated.
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Natural regeneration on seismic lines influences movement behaviour of wolves and grizzly bears
PLoS ONE, 2018Co-Authors: Laura Finnegan, Jerome Cranston, Lalenia Neufeld, Fiona Schmiegelow, Karine E. Pigeon, Mark Hebblewhite, Julie Duval, Marco Musiani, Gordon B. StenhouseAbstract:Across the boreal forest of Canada, habitat disturbance is the ultimate cause of Caribou (Rangifer Tarandus Caribou) declines. Habitat restoration is a focus of Caribou recovery efforts, with a goal to finding ways to reduce predator use of disturbances, and Caribou-pred-ator encounters. One of the most pervasive disturbances within Caribou ranges in Alberta, Canada are seismic lines cleared for energy exploration. Seismic lines facilitate predator movement, and although vegetation on some seismic lines is regenerating, it remains unknown whether vegetation regrowth is sufficient to alter predator response. We used Light Detection and Ranging (LiDAR) data, and GPS locations, to understand how vegeta-tion and other attributes of seismic lines influence movements of two predators, wolves (Canis lupus) and grizzly bears (Ursus arctos). During winter, wolves moved towards seis-mic lines regardless of vegetation height, while during spring wolves moved towards seismic lines with higher vegetation. During summer, wolves moved towards seismic lines with lower vegetation and also moved faster near seismic lines with vegetation
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billion dollar boreal woodland Caribou and the biodiversity impacts of the global oil and gas industry
Biological Conservation, 2017Co-Authors: Mark HebblewhiteAbstract:Abstract Awareness of the impact of the global energy industry and associated landuse change on biodiversity conservation has been steadily growing amongst conservation biologists. Across Canada, 28 of 57 populations of boreal woodland Caribou ( Rangifer Tarandus Caribou) are declining and 20 of 25 southern mountain populations are in decline with several recent high-profile extirpations. Declines stem from widespread landuse change from energy development and forestry that will take decades to recover, if ever. In Western Canada's Boreal forest, a globally significant oil and gas industry has emerged that is the biggest source of foreign oil to US markets. All woodland Caribou populations overlapping oil and gas development in oil-rich Alberta are in rapid decline, shrinking by 50% every 8 years. After a decade of delay, the Federal government released recovery plans under the Canadian Species-at-Risk Act (SARA) in 2012 and 2014 for these two Caribou ecotypes, and will audit provincial compliance in 2017. Yet recovery actions have been inadequate, and have relied on wolf control as a short-term solution. Given the stark reality, conservation triage might be expected. Instead, the conservation objective at Federal and Provincial levels remains legally committed to recovery of all populations despite the paradox of continued declines. I suggest the reason for ineffective conservation planning is the staggering cost of effective habitat protection that far exceeds $150 billion (CDN) in Alberta alone. Declines of woodland Caribou also allegedly violate Canadian Aboriginal treaty rights that have been challenged in court. This complex conservation case-study urgently illustrates the need for strategic conservation triage at provincial and national levels. And more generally, Caribou conservation demonstrates the challenge of using national endangered species legislation to retroactively counteract the global energy industry without strategic conservation planning coordinated with energy and cultural policies.
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addendum to managing wolves canis lupus to recover threatened woodland Caribou Rangifer Tarandus Caribou in alberta 1
Canadian Journal of Zoology, 2015Co-Authors: Dave Hervieux, Mark Hebblewhite, Dave Stepnisky, Michelle BaconAbstract:Managing predators to restore threatened or endangered species is often controversial. Hervieux et al. (2014; Can. J. Zool. 92(12): 1029–1037) report on the efficacy of wolf (Canis lupus L., 1758) reduction as a recovery strategy in the Little Smoky population of boreal woodland Caribou (Rangifer Tarandus Caribou (Gmelin, 1788)) range in Alberta, which generated a lot of media attention. As such, the authors were invited by the journal editor who handled the original paper to write this addendum to provide clarification regarding the methodology used in the original paper. Wolf reduction was conducted by Government personnel in accordance with appropriate policy and laws (i.e., federal and provincial Species at Risk Acts; Alberta Wildlife Act; Alberta Woodland Caribou Policy). University-based researchers were involved only in data analysis and writing, and thus did not require approval by a university-based animal welfare board. Collaboration between independent university-based scientists and government...
Heiko U Wittmer - One of the best experts on this subject based on the ideXlab platform.
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viability of mountain Caribou in british columbia canada effects of habitat change and population density
Biological Conservation, 2010Co-Authors: Heiko U Wittmer, Robert N M Ahrens, Bruce N MclellanAbstract:Population viability analyses (PVA) are frequently employed to develop recovery plans and inform management of endangered species. Translating results from PVA into meaningful management recommendations often depends on an understanding of how population parameters change with environmental conditions as well as population density. The decline of mountain Caribou (Rangifer Tarandus Caribou) in British Columbia, Canada, is believed to be caused by apparent competition with alternative prey species following changes to the forest age structure from timber harvest and wildfire. In addition, populations have been shown to decline at faster rates at low population density. To evaluate the potential effects of habitat change and population density on population persistence, we used stochastic projection models for 10 distinct populations varying in initial size from 350 radiocollared Caribou between 1984 and 2004. We then compared the results of the initial model to a set of models that evaluated the effects of habitat conditions and population density via their expected relationships to female adult survival. Assuming that vital rates remain constant over a 200-year time frame, only three populations have high probabilities (>0.95) of extinction. When models incorporate the declines in adult female survival know to occur with increasing proportions of young forest and declining population densities, all 10 populations are predicted to decline to extinction within <200 years. Based on our results, we suggest that PVA models that fail to incorporate the effects of changes in vital rates with habitat and population density may lead to overly optimistic assessments of the probability of population persistence in endangered species.
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changes in landscape composition influence the decline of a threatened woodland Caribou population
Journal of Animal Ecology, 2007Co-Authors: Heiko U Wittmer, Bruce N Mclellan, Robert Serrouya, Clayton D AppsAbstract:Summary 1 Large-scale habitat loss is frequently identified with loss of biodiversity, but examples of the direct effect of habitat alterations on changes in vital rates remain rare. Quantifying and understanding the relationship between habitat composition and changes in vital rates, however, is essential for the development of effective conservation strategies. 2 It has been suggested that the decline of woodland Caribou Rangifer Tarandus Caribou populations in North America is precipitated by timber harvesting that creates landscapes of early seral forests. Such habitat changes have altered the predator–prey system resulting in asymmetric predation, where predators are maintained by alternative prey (i.e. apparent competition). However, a direct link between habitat condition and Caribou population declines has not been documented. 3 We estimated survival probabilities for the threatened arboreal lichen-feeding ecotype of woodland Caribou in British Columbia, Canada, at two different spatial scales. At the broader scale, observed variation in adult female survival rates among 10 distinct populations (range = 0·67–0·93) was best explained by variation in the amount of early seral stands within population ranges and population density. At the finer scale, home ranges of Caribou killed by predators had lower proportions of old forest and more mid-aged forest as compared with multi-annual home ranges where Caribou were alive. 4 These results are consistent with predictions from the apparent competition hypothesis and quantify direct fitness consequences for Caribou following habitat alterations. We conclude that apparent competition can cause rapid population declines and even extinction where changes in species composition occur following large scale habitat change.
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factors influencing variation in site fidelity of woodland Caribou Rangifer Tarandus Caribou in southeastern british columbia
Canadian Journal of Zoology, 2006Co-Authors: Heiko U Wittmer, Bruce N Mclellan, Frederick W HoveyAbstract:Where predation is a major limiting factor, it has been postulated that woodland Caribou (Rangifer Tarandus Caribou (Gmelin, 1788)) reduce movements to minimize contact with predators and exhibit fidelity to seasonal ranges. We examined fidelity behaviour within season and among years of woodland Caribou based on locations of 65 radio-collared individuals in British Columbia, Canada. We used average linear distances between all possible pairs of radiolocations of individuals to assess fidelity. Among-year interlocation distances were similar to within-season interlocation distances during summer, indicating that Caribou did not shift their distribution during seasons when they were most vulnerable to predation. Among-year interlocation distances were significantly greater than within-season interlocation distances during both early winter and late winter, indicating that individual Caribou shifted their distribution among winters. The amount that an individual’s distribution shifted among winters varied a...
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the role of predation in the decline and extirpation of woodland Caribou
Oecologia, 2005Co-Authors: Heiko U Wittmer, A R E Sinclair, Bruce N MclellanAbstract:To select appropriate recovery strategies for endangered populations, we must understand the dynamics of small populations and distinguish between the possible causes that drive such populations to low numbers. It has been suggested that the pattern of population decline may be inversely density-dependent with population growth rates decreasing as populations become very small; however, empirical evidence of such accelerated declines at low densities is rare. Here we analyzed the pattern of decline of a threatened population of woodland Caribou (Rangifer Tarandus Caribou) in British Columbia, Canada. Using information on the instantaneous rate of increase relative to Caribou density in suitable winter foraging habitat, as well as on pregnancy rates and on causes and temporal distribution of mortalities from a sample of 349 radiocollared animals from 15 subpopulations, we tested 3 hypothesized causes of decline: (a) food regulation caused by loss of suitable winter foraging habitat, (b) predation-sensitive foraging caused by loss of suitable winter foraging habitat and (c) predation with Caribou being secondary prey. Population sizes of Caribou subpopulations ranged from 500 individuals. Our results showed that the rates of increase of these subpopulations varied from −0.1871 to 0.0496 with smaller subpopulations declining faster than larger subpopulations. Rates of increase were positively related to the density of Caribou in suitable winter foraging habitat. Pregnancy rates averaged 92.4% ±2.24 and did not differ among subpopulations. In addition, we found predation to be the primary cause of mortality in 11 of 13 subpopulations with known causes of mortality and predation predominantly occurred during summer. These results are consistent with predictions that Caribou subpopulations are declining as a consequence of increased predation. Recovery of these woodland Caribou will thus require a multispecies perspective and an appreciation for the influence of inverse density dependence on population trajectories.
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population dynamics of the endangered mountain ecotype of woodland Caribou Rangifer Tarandus Caribou in british columbia canada
Canadian Journal of Zoology, 2005Co-Authors: Heiko U Wittmer, Dale R. Seip, Bruce N Mclellan, James A Young, Trevor A Kinley, Glen S Watts, Dennis HamiltonAbstract:We used census results and radiotelemetry locations of >380 collared individuals sampled over the entire distribution of the endangered mountain ecotype of woodland Caribou (Rangifer Tarandus Caribou (Gmelin, 1788)) in British Columbia, Canada, to delineate population structure and document the size and trend of the identified popula- tions. We also describe the spatial pattern of decline and the causes and timing of adult mortality and provide estimates of vital rates necessary to develop a population viability analysis. Our results indicate that the abundance of mountain Caribou in British Columbia is declining. We found adult female annual survival rates below annual survival rates com- monly reported for large ungulates. The major proximate cause of population decline appears to be predation on adult Caribou. Spatial patterns of population dynamics revealed a continuous range contraction and an increasing fragmenta- tion of mountain Caribou into smaller, isolated subpopulations. The population fragmentation process predominantly oc- curs at the outer boundaries of the current distribution. Our results indicate that recovery strategies for mountain Caribou should be directed at factors contributing to the fragmentation and isolation of mountain Caribou populations as well as management strategies aimed at increasing adult survival.
Laura Finnegan - One of the best experts on this subject based on the ideXlab platform.
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Terrestrial Bryophyte and Lichen Responses to Canopy Opening in Pine-Moss-Lichen Forests
MDPI AG, 2019Co-Authors: Dale H. Vitt, Laura Finnegan, Melissa HouseAbstract:Pinus contorta-dominated montane forests of western Canada with relatively dense tree canopies have ground layers with abundant bryophytes, especially the feather mosses (Pleurozium schreberi and Hylocomium splendens), while those with more open canopies are dominated by species of reindeer lichens, especially Cladonia arbuscula s.l. and C. Rangiferina s.l. Woodland Caribou (Rangifer Tarandus Caribou), which are a threatened species in Alberta, prefer open, Cladonia-dominated forests for their winter food supply. This study investigated if opening the canopy by thinning mature montane forests of the Canadian Rocky Mountain foothills would change the abundance of lichens and bryophytes. In 1997, forests were thinned by removing 20%, 40%, and 60% by volume. In 2016, 19 years after treatment, we re-surveyed a subset of these plots (n = 97) for lichen and bryophyte abundance and species richness by utilizing the amount of canopy opening at the plot level as our prime gradient. We then used ordination to determine the relationship of control plots to treatment plots. In uncut forest, the control plots were highly variable, but were mostly dominated by feather mosses, with little or no bare ground. Feather moss abundance was lower in treatment plots when compared to control plots, while cover of bare ground was greater. Overall, 19 years after treatment, we found that, in treatment plots, lichen abundance remained stable or slightly increased, feather mosses decreased markedly, and unoccupied space was double that of the control plots. We conclude that the canopy opening had little effect on understory and ground layer diversity, but considering species abundance (1) bryophytes have not recovered after canopy opening, (2) populations of reindeer lichens increased marginally, but have not colonized areas left bare from bryophyte dieback, and (3), after 19 years there, remains unoccupied areas of bare ground in plots with a reduced canopy cover. Our study demonstrated that, with canopy cover reduction resulting from forest thinning operations, the ground layer diversity is maintained, but recovery of ground layers in old-growth pine-dominated forests is not promoted. Therefore, timber harvest that partially opens the tree canopy is unlikely to benefit Caribou by augmenting or accelerating winter food availability and habitat suitability for Caribou
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natural regeneration on seismic lines influences movement behaviour of wolves and grizzly bears
PLOS ONE, 2018Co-Authors: Laura Finnegan, Jerome Cranston, Lalenia Neufeld, Fiona Schmiegelow, Karine E. Pigeon, Mark Hebblewhite, Julie Duval, Marco Musiani, Gordon B. StenhouseAbstract:Across the boreal forest of Canada, habitat disturbance is the ultimate cause of Caribou (Rangifer Tarandus Caribou) declines. Habitat restoration is a focus of Caribou recovery efforts, with a goal to finding ways to reduce predator use of disturbances, and Caribou-predator encounters. One of the most pervasive disturbances within Caribou ranges in Alberta, Canada are seismic lines cleared for energy exploration. Seismic lines facilitate predator movement, and although vegetation on some seismic lines is regenerating, it remains unknown whether vegetation regrowth is sufficient to alter predator response. We used Light Detection and Ranging (LiDAR) data, and GPS locations, to understand how vegetation and other attributes of seismic lines influence movements of two predators, wolves (Canis lupus) and grizzly bears (Ursus arctos). During winter, wolves moved towards seismic lines regardless of vegetation height, while during spring wolves moved towards seismic lines with higher vegetation. During summer, wolves moved towards seismic lines with lower vegetation and also moved faster near seismic lines with vegetation <0.7 m. Seismic lines with lower vegetation height were preferred by grizzly bears during spring and summer, but there was no relationship between vegetation height and grizzly bear movement rates. These results suggest that wolves use seismic lines for travel during summer, but during winter wolf movements relative to seismic lines could be influenced by factors additional to movement efficiency; potentially enhanced access to areas frequented by ungulate prey. Grizzly bears may be using seismic lines for movement, but could also be using seismic lines as a source of vegetative food or ungulate prey. To reduce wolf movement rate, restoration could focus on seismic lines with vegetation <1 m in height. However our results revealed that seismic lines continue to influence wolf movement behaviour decades after they were built, and even at later stages of regeneration. Therefore it remains unknown at what stage of natural regeneration, if any, wolves cease to respond to seismic lines. To reduce wolf response to seismic lines, active restoration tactics like blocking seismic lines and tree planting, along with management of alternate prey, could be evaluated.
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Natural regeneration on seismic lines influences movement behaviour of wolves and grizzly bears
PLoS ONE, 2018Co-Authors: Laura Finnegan, Jerome Cranston, Lalenia Neufeld, Fiona Schmiegelow, Karine E. Pigeon, Mark Hebblewhite, Julie Duval, Marco Musiani, Gordon B. StenhouseAbstract:Across the boreal forest of Canada, habitat disturbance is the ultimate cause of Caribou (Rangifer Tarandus Caribou) declines. Habitat restoration is a focus of Caribou recovery efforts, with a goal to finding ways to reduce predator use of disturbances, and Caribou-pred-ator encounters. One of the most pervasive disturbances within Caribou ranges in Alberta, Canada are seismic lines cleared for energy exploration. Seismic lines facilitate predator movement, and although vegetation on some seismic lines is regenerating, it remains unknown whether vegetation regrowth is sufficient to alter predator response. We used Light Detection and Ranging (LiDAR) data, and GPS locations, to understand how vegeta-tion and other attributes of seismic lines influence movements of two predators, wolves (Canis lupus) and grizzly bears (Ursus arctos). During winter, wolves moved towards seis-mic lines regardless of vegetation height, while during spring wolves moved towards seismic lines with higher vegetation. During summer, wolves moved towards seismic lines with lower vegetation and also moved faster near seismic lines with vegetation
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integrating multiple analytical approaches to spatially delineate and characterize genetic population structure an application to boreal Caribou Rangifer Tarandus Caribou in central canada
Conservation Genetics, 2010Co-Authors: Mark C Ball, Laura Finnegan, Micheline Manseau, Paul J WilsonAbstract:Individual-based clustering (IBC) methods have become increasingly popular for the characterization and delineation of genetic population units for numerous species. These methods delineate populations based on the genetic assumptions of a breeding unit which may provide a better representation of the behaviour of the species. The increasing use of IBC has resulted in the development of several analytical models all of which vary in their theoretical assumptions to infer genetic population structure. In this paper, we report a comparative strategy utilizing three IBC methods to characterize the spatial genetic structure of the boreal population of woodland Caribou (Rangifer Tarandus Caribou) in central Canada. In addition, we implement both tests for isolation-by-distance (IBD) and frequency-based assignment tests to validate the consensus genetic clusters as defined by IBC. We also compare indirect metrics of genetic diversity and gene flow using both a priori defined herds and the IBC defined populations. Although our results show some concordance between both pre-defined herds and IBC derived genetic clusters, the IBC analyses identified a cluster that was cryptic to observation-based Caribou herds and found no difference between several adjacent herds. By comparing multiple IBC methods and integrating both IBD and indirect genetic diversity metrics a posteriori, our strategy provides an effective means to delineate wildlife population structure and accurately assess genetic diversity and connectivity.
Gordon B. Stenhouse - One of the best experts on this subject based on the ideXlab platform.
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natural regeneration on seismic lines influences movement behaviour of wolves and grizzly bears
PLOS ONE, 2018Co-Authors: Laura Finnegan, Jerome Cranston, Lalenia Neufeld, Fiona Schmiegelow, Karine E. Pigeon, Mark Hebblewhite, Julie Duval, Marco Musiani, Gordon B. StenhouseAbstract:Across the boreal forest of Canada, habitat disturbance is the ultimate cause of Caribou (Rangifer Tarandus Caribou) declines. Habitat restoration is a focus of Caribou recovery efforts, with a goal to finding ways to reduce predator use of disturbances, and Caribou-predator encounters. One of the most pervasive disturbances within Caribou ranges in Alberta, Canada are seismic lines cleared for energy exploration. Seismic lines facilitate predator movement, and although vegetation on some seismic lines is regenerating, it remains unknown whether vegetation regrowth is sufficient to alter predator response. We used Light Detection and Ranging (LiDAR) data, and GPS locations, to understand how vegetation and other attributes of seismic lines influence movements of two predators, wolves (Canis lupus) and grizzly bears (Ursus arctos). During winter, wolves moved towards seismic lines regardless of vegetation height, while during spring wolves moved towards seismic lines with higher vegetation. During summer, wolves moved towards seismic lines with lower vegetation and also moved faster near seismic lines with vegetation <0.7 m. Seismic lines with lower vegetation height were preferred by grizzly bears during spring and summer, but there was no relationship between vegetation height and grizzly bear movement rates. These results suggest that wolves use seismic lines for travel during summer, but during winter wolf movements relative to seismic lines could be influenced by factors additional to movement efficiency; potentially enhanced access to areas frequented by ungulate prey. Grizzly bears may be using seismic lines for movement, but could also be using seismic lines as a source of vegetative food or ungulate prey. To reduce wolf movement rate, restoration could focus on seismic lines with vegetation <1 m in height. However our results revealed that seismic lines continue to influence wolf movement behaviour decades after they were built, and even at later stages of regeneration. Therefore it remains unknown at what stage of natural regeneration, if any, wolves cease to respond to seismic lines. To reduce wolf response to seismic lines, active restoration tactics like blocking seismic lines and tree planting, along with management of alternate prey, could be evaluated.
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Natural regeneration on seismic lines influences movement behaviour of wolves and grizzly bears
PLoS ONE, 2018Co-Authors: Laura Finnegan, Jerome Cranston, Lalenia Neufeld, Fiona Schmiegelow, Karine E. Pigeon, Mark Hebblewhite, Julie Duval, Marco Musiani, Gordon B. StenhouseAbstract:Across the boreal forest of Canada, habitat disturbance is the ultimate cause of Caribou (Rangifer Tarandus Caribou) declines. Habitat restoration is a focus of Caribou recovery efforts, with a goal to finding ways to reduce predator use of disturbances, and Caribou-pred-ator encounters. One of the most pervasive disturbances within Caribou ranges in Alberta, Canada are seismic lines cleared for energy exploration. Seismic lines facilitate predator movement, and although vegetation on some seismic lines is regenerating, it remains unknown whether vegetation regrowth is sufficient to alter predator response. We used Light Detection and Ranging (LiDAR) data, and GPS locations, to understand how vegeta-tion and other attributes of seismic lines influence movements of two predators, wolves (Canis lupus) and grizzly bears (Ursus arctos). During winter, wolves moved towards seis-mic lines regardless of vegetation height, while during spring wolves moved towards seismic lines with higher vegetation. During summer, wolves moved towards seismic lines with lower vegetation and also moved faster near seismic lines with vegetation