Landscape of risk: responses of grey wolves to lethal control in a mosaic landscape

European Journal of Wildlife Research, Год журнала: 2025, Номер 71(2)

Опубликована: Фев. 25, 2025

Язык: Английский

Causal attribution from retrospective data in Canada's woodland caribou system

Ecological Applications, Год журнала: 2025, Номер 35(3)

Опубликована: Апрель 1, 2025

Forecasting the benefits of management interventions intended to improve ecological conditions requires a causal understanding factors that lead system change. The attribution factor is defined as difference between outcome observed in presence and would have been factor's absence, is, counterfactual condition. Estimating this contrast relatively straightforward, where matched or randomized controls are available approximate However, researchers must reason retrospectively from observational data not available. In case, challenge establishing estimating true counterfactual, resulted absence factor, given it was present. Causal analysis permits estimation counterfactuals data, assuming model captures all common causes exposure outcome, independent other (i.e., exogenous), same directional change for units monotonic). I estimated habitat-related recruitment rates Canada's boreal population woodland caribou (Rangifer tarandus caribou). Aggregate habitat disturbance had low (17.6%). Attribution greater (29.5%) when disaggregated into different associated with pathways decline. considered nevertheless rarely exceeded 50%, suggesting there systematic and/or stochastic can limit effectiveness current recovery actions. More effort required understand these how they might be managed probability successful recovery.

Язык: Английский

Mixed evidence for disturbance‐mediated apparent competition for declining caribou in western British Columbia, Canada

Journal of Wildlife Management, Год журнала: 2025, Номер unknown

Опубликована: Май 19, 2025

Abstract Understanding causal mechanisms of decline for species at risk is critical effective conservation. Caribou ( Rangifer tarandus ) face threats from habitat loss and degradation due to human activities, many caribou populations across Canada have experienced dramatic declines in recent decades. Disturbance‐mediated apparent competition (DMAC) has been implicated these declines, but its generality questioned, particularly low‐productivity ranges. The DMAC hypothesis leads the following predictions: 1) a vegetation productivity pulse after disturbance, 2) primary ungulate prey attraction disturbed areas, 3) predator 4) increased predation overlapping use with predators. We tested predictions declining Itcha‐Ilgachuz population, located Chilcotin Plateau region west‐central British Columbia, Canada. used remotely sensed index examine recovery patterns disturbance camera traps Bayesian mixed effects negative binomial regression models estimate responses prey, predator, relative abundance landscape disturbances <40 years old, interacting species, other features. identified harvested burnt forest patches, overall was lower than ranges where occurs. Primary moose Alces alces mule deer Odocoileus hemionus ), showed strong positive areas weak forest. For predators, wolves Canis lupus black bears Ursus americanus grizzly arctos were positively associated while coyotes latrans lynx Lynx canadensis more strongly snowshoe hare Lepus wolverines Gulo gulo not any focal species. Wolves, bears, coyotes, responded burned areas. did reduced forests or burns, potentially increasing their overlap Overall, we found support stronger evidence pathway mediated by fire, rather harvest. recommend further research action on wildfire management this including monitoring population trends response management. Our results emphasize context‐dependency underscore need population‐specific knowledge effectively conserve threatened

Язык: Английский