Demographic and behavioural response of woodland caribou to forest harvesting

2008 ◽  
Vol 38 (11) ◽  
pp. 2837-2849 ◽  
Author(s):  
Réhaume Courtois ◽  
André Gingras ◽  
Daniel Fortin ◽  
Aïssa Sebbane ◽  
Bruno Rochette ◽  
...  

We investigated whether woodland caribou ( Rangifer tarandus caribou ) would remain in a 2772 km2 area in eastern Quebec where the forest management plan included the preservation of large forest blocks (35–182 km2) linked with >400 m wide corridors and where cuts were amalgamated in large zones. To evaluate changes in caribou abundance and habitat selection, we conducted five aerial surveys and followed by telemetry 13 to 22 female caribou each year, from March 1998 to March 2005. Caribou numbers declined by 59% between 1999 and 2001 but gradually recovered to initial abundance. Female survival increased from 73.3% in 1999 to 87.3%–93.4% in 2004 and 2005. Caribou selected protected blocks, used corridors in proportion to their availability, and avoided logged areas. They preferred closed conifer stands without terrestrial lichens and open conifer stands with or without terrestrial lichens throughout the study. Open habitats (clearcuts and burns), regenerating sites, mixed and deciduous stands, and water bodies were avoided. The main zones used by caribou gradually shifted towards the southwest of the study area, likely as a result of disturbance and habitat loss due to logging of mature conifers in the east. We conclude that caribou numbers were maintained within the managed area as a result of the presence of protected blocks and uncut continuous forest.

2013 ◽  
Vol 91 (12) ◽  
pp. 872-882 ◽  
Author(s):  
D. Hervieux ◽  
M. Hebblewhite ◽  
N.J. DeCesare ◽  
M. Russell ◽  
K. Smith ◽  
...  

Nowhere across Canada is the continued persistence of woodland caribou (Rangifer tarandus caribou (Gmelin, 1788)) more uncertain than in Alberta due to widespread industrial development. A recent Government of Canada critical habitat review determined that habitat conditions within all Alberta boreal ecotype caribou ranges are unlikely or very unlikely to allow for self-sustaining caribou populations. This habitat-based assessment was based only indirectly on empirical population trends. Here, we estimated empirical population trend and growth rate (λ) for 13 of Alberta’s 16 remaining woodland caribou populations (plus one adjacent population from Saskatchewan) from 1994 to 2012 using demographic monitoring of adult female survival and calf recruitment. We captured and radio-collared a total of 1337 adult female caribou in 14 populations and estimated the mean annual adult female survival across all populations as 0.851. We conducted 158 late-winter calf recruitment surveys across the 14 populations classifying 20 872 caribou and estimated mean recruitment of 0.154 calves/cow (i.e., 0.077 female calves/cow). We then combined annual estimates of adult female survival and female calf recruitment within each population in a simple age-structured population model to estimate population trend. Annual population growth rate across caribou populations averaged 0.918, and was significantly declining, λ < 1.0, for 10 of the 14 caribou populations. Our results confirm that woodland caribou are declining rapidly (with a realized decline of approximately 50% every 8 years) across Alberta, and support conclusions from previous habitat-based assessments that the population viability of caribou is currently compromised, supporting development and implementation of recovery actions to reverse trends.


Rangifer ◽  
1986 ◽  
Vol 6 (2) ◽  
pp. 43 ◽  
Author(s):  
W. K. Brown ◽  
J. Huot ◽  
P. Lamothe ◽  
S. Luttich ◽  
M. Paré ◽  
...  

<p>Recent studies of woodland caribou (Rangifer tarandus caribou) in northern Quebec and central Labrador have demonstrated similar patterns of seasonal movements and distribution among four herds. Aerial surveys and radio-telemetry indicated that animals occupied forest-wetland habitat at densities of 0.03 caribou km2, or lower, for most of the year. Although females were widely dispersed at calving individuals demonstrated fidelity toward specific calving locations, in successive years. Caribou did not form large post-calving aggregations. Movement was greatest in the spring, prior to calving, and in the fall, during or immediately after rutting. Caribou were generally sedentary during summer and winter, although some moved relatively long distances to late-winter range. Although the herds occupy continuous range across Quebec and Labrador, our data indicate that the herds are largely discreete and should be managed individually.</p>


1988 ◽  
Vol 66 (2) ◽  
pp. 475-479 ◽  
Author(s):  
Murray W. Lankester ◽  
Stu Luttich

Fifty-eight percent of woodland caribou (Rangifer tarandus caribou) of the George River herd, Labrador, were infected with up to 110 giant American liver flukes (Fascioloides magna). The prevalence and intensity of infection did not differ between 2 sampling years or between sexes. Prevalence tended to increase with age while intensity did not differ among age groups. Liver weight increased with intensity of infection but condition, as measured by the mean depth of back fat, did not differ between infected and uninfected animals. Caribou must be considered a suitable host of F. magna since the growth and maturation of the parasite and lesions produced in Rangifer resemble those in deer and wapiti.


1994 ◽  
Vol 30 (2) ◽  
pp. 195-200 ◽  
Author(s):  
Patricia J. Holman ◽  
Kris Petrini ◽  
Jack Rhyan ◽  
Q. G. Wagner

2014 ◽  
Vol 92 (12) ◽  
pp. 1029-1037 ◽  
Author(s):  
Dave Hervieux ◽  
Mark Hebblewhite ◽  
Dave Stepnisky ◽  
Michelle Bacon ◽  
Stan Boutin

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 λ 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.


Rangifer ◽  
2000 ◽  
Vol 20 (5) ◽  
pp. 85 ◽  
Author(s):  
Kimberley G. Brown ◽  
Campbell Elliott ◽  
Francois Messier

Woodland caribou (Rangifer tarandus caribou) in the boreal forest are believed threatened by human encroachment and associated disturbances such as resource exploration and extraction. We radiocollared and monitored fifteen female woodland caribou in central Manitoba, from 1995 to 1997, to obtain information on their population range, seasonal distribution and movements in relation to forestry concerns. The population ranged over 4600 km2 within a large peatland system and concentrated their activities in two areas for both the summer and winter seasons. Females were relatively more solitary during the summer and exhibited fidelity to specific calving and summering areas averaging 83.4 km2. Individual wintering locations varied between years and among individuals. Post-rut and pre-calving mixed-sex aggregations occurred on the southern portion of the herds range. Caribou from the northern part of the range utilized a traditional travel corridor moving as far as 65 km to access the aggregation areas and their summer or winter ranges. Adult survival during the study period averaged 0.90 (95% CI, 0.80-1.00). Survival of the 1995 cohort appeared to be high as indicated by the 0.65:1 calf-cow ratio, and 30 &plusmn; 7% calf composition of observed caribou in the autumn of 1995. The annual rate of change (A,) of 1.19 (95% CI, 1.02-1.36) from January to November of 1995 indicated rhat the population was increasing at that time.


2020 ◽  
Author(s):  
Heiko Wittmer ◽  
BN McLellan ◽  
DR Seip ◽  
JA Young ◽  
TA Kinley ◽  
...  

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 populations. 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 commonly 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 fragmentation of mountain caribou into smaller, isolated subpopulations. The population fragmentation process predominantly occurs 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. © 2005 NRC Canada.


Sign in / Sign up

Export Citation Format

Share Document