Gingras J.,Laval University |
Couturier S.,Direction de lExpertise sur la Faune et Ses Habitats |
Cote S.D.,Laval University |
Tremblay J.-P.,Laval University
Journal of Wildlife Management | Year: 2014
Moose (Alces alces) populations exceed 3individuals/km2 in some wildlife reserves and parks of northeastern Canada. Heavy browsing pressure at such densities is potentially altering the ecological integrity of forests with eventual negative consequences for moose. We hypothesized that regulation by resources would be limited by the capacity of female moose to modulate their reproductive strategies to maintain high fertility despite a decline in body condition. We observed a 20-33% decline in rump fat thickness in males and females, respectively, from the high density Matane Wildlife Reserve in Eastern Québec in October compared to an adjacent population. We also observed a lower mass of the peroneus group of muscles for males (-3%) and prime-aged females (-8%) in the Matane Wildlife Reserve than in the adjacent population. Females from the Matane Wildlife Reserve population had a lower twinning ovulation rate (1 out of 20 vs. 7 out of 21 ovulating females in the adjacent population) but >15% higher overall ovulation rate. Our results suggest that female moose can maintain high fertility despite a decline in body condition, by reducing their litter size at ovulation and conserving energy to increase the probability of annual reproduction. The adjustment of female reproductive strategies illustrates the plasticity of moose in response to decreasing habitat quality. We conclude that in the absence of specialist predators, equilibrium with forage is unlikely for large herbivores in the short or mid-term. Active management of moose populations is likely required to maintain the ecological integrity of boreal forests. © 2014 The Wildlife Society.
Leblond M.,University of Quebec at Rimouski |
Frair J.,Laval University |
Fortin D.,Laval University |
Dussault C.,Direction de lexpertise sur la Faune et ses Habitats |
And 2 more authors.
Landscape Ecology | Year: 2011
Efforts in isolating the relative effects of resources and disturbances on animal-distribution patterns remain hindered by the difficulty of accounting for multiple scales of resource selection by animals with seasonally dynamic drivers. We developed multi-scale, seasonal models to explore how local resource selection by the threatened forest-dwelling woodland caribou (Rangifer tarandus caribou) was influenced by both broad-scale landscape context and local resource heterogeneity in the intensively managed region of Charlevoix, Québec, Canada, located on the southern border of the North American caribou range. We estimated resource selection functions using 23 GPS-collared caribou monitored from 2004 to 2006 and landscape data on vegetation classes, terrain conditions, and roads. We found evidence of thresholds in road "proximity" effects (up to 1. 25 km), which underscores the importance of including landscape context variables in addition to locally measured variables, and of fitting seasonal-specific models given temporal variation in the magnitude of selection and optimal scale of measurement. Open lichen woodlands were an important cover type for caribou during winter and spring, whereas deciduous forests, wetlands, and even young disturbed stands became important during calving and summer. Caribou consistently avoided roads and rugged terrain conditions at both local and landscape levels. Landscape context fundamentally constrains the choices available to animals, and we showed that failing to consider landscape context, or arbitrarily choosing an inappropriate scale for measuring covariates, may provide biased inferences with respect to habitat selection patterns. Effective habitat management for rare or declining species should carefully consider the hierarchical nature of habitat selection. © 2011 Springer Science+Business Media B.V.
Leclerc V.,University of Quebec at Chicoutimi |
Sirois P.,University of Quebec at Chicoutimi |
Berube P.,Direction de lexpertise sur la faune et ses habitats
Boreal Environment Research | Year: 2011
Any factor modifying early growth in fishes could lead to large recruitment variations. We investigated the impact of forest harvesting on growth rate and length-at-age of larval and juvenile yellow perch (Perca flavescens) and on the trophodynamics in small oligotrophic Canadian Boreal Shield lakes. Yellow perch, phytoplankton, and zooplankton were sampled in August or early September in three consecutive years (2003, 2004 and 2005) from three unperturbed lakes and from three lakes that had had logging in their watershed catchment zones after the first year of sampling. Two years after the perturbation, larval and juvenile growth rate and length-at-age of yellow perch, as well as Chl a, were significantly higher in lakes perturbed by forest harvesting than in unperturbed ones. Our results support the hypothesis that early growth of yellow perch has been favoured in perturbed lakes. This may have been due to post-harvest enhancements in nutrients and dissolved organic carbon concentrations, likely generating bottom-up changes in larval and juvenile yellow perch feeding conditions such as increased prey abundance and visibility thus, stimulating growth.© 2011.
Grosman P.D.,Concordia University at Montréal |
Jaeger J.A.G.,Concordia University at Montréal |
Biron P.M.,Concordia University at Montréal |
Dussault C.,Direction de lexpertise sur la faune et ses habitats |
Ouellet J.-P.,University of Quebec at Rimouski
Ecological Modelling | Year: 2011
Moose-vehicle collisions are a frequent traffic-safety issue, particularly in northern regions where moose are attracted to the near-road areas because they can consume sodium from de-icing salts that accumulate in pools at snowmelt. Moose that find salt pools near roads tend to remember their location and to re-visit them to get the sodium they need in their diet. This study investigated the trade-off between road avoidance and salt pool spatial memory in the movement behaviour of moose using an agent-based model to determine how the interplay of these two factors influences the frequency of road crossings in the Laurentides Wildlife Reserve (Québec, Canada). Mitigation measures studied were the removal of roadside salt pools and the construction of compensatory salt pools away from the road shoulder. A GPS telemetry program of moose in the study area was used to validate our model. The model moose with both road avoidance and salt pool spatial memory activated produced the best results when comparing to the real moose data. Results show that both road avoidance and salt pool spatial memory significantly affect moose road crossings, but that road avoidance explains most of the variance. Road avoidance tended to decrease the number of moose crossings, but this decrease was partly compensated by the spatial memory of salt pools which typically increased the likelihood that moose will cross the road. The trade-off between road avoidance and salt pool memory was largest when original salt pools were maintained. In simulations where road avoidance and salt pool memory were both turned off, the impact of mitigation measures on the number of road crossings was lowest. For the most realistic moose behavior, the management scenarios resulted in reductions in road crossings between 22% and 79%, and the best scenario is to completely remove roadside salt pools. If compensation salt pools are used, they should be located as far as possible from the roads (beyond 500. m) to have an impact on moose road crossings. © 2011 Elsevier B.V.