Boreal predator co‐occurrences reveal shared use of seismic lines in a working landscape

Abstract

Interspecific interactions are an integral aspect of ecosystem functioning that may be disrupted in an increasingly anthropocentric world. Industrial landscape change creates a novel playing field on which these interactions take place, and a key question for wildlife managers is whether and how species are able to coexist in such working landscapes. Using camera traps deployed in northern Alberta, we surveyed boreal predators to determine whether interspecific interactions affected occurrences of black bears (Ursus americanus), coyotes (Canis latrans), and lynx (Lynx canadensis) within a landscape disturbed by networks of seismic lines (corridors cut for seismic exploration of oil and gas reserves). We tested hypotheses of species interactions across one spatial‐only and two spatiotemporal (daily and weekly) scales. Specifically, we hypothesized that (1) predators avoid competition with the apex predator, gray wolf (Canis lupus), (2) they avoid competition with each other as intraguild competitors, and (3) they overlap with their prey. All three predators overlapped with wolves on at least one scale, although models at the daily and weekly scale had substantial unexplained variance. None of the predators showed avoidance of intraguild competitors or overlap with prey. These results show patterns in predator space use that are consistent with both facilitative interactions or shared responses to unmeasured ecological cues. Our study provides insight into how predator species use the working boreal landscape in relation to each other, and highlights that predator management may indirectly influence multiple species through their interactions.

Cumulative effects of human footprint, natural features and predation risk best predict seasonal resource selection by white-tailed deer

“…Seismic line restoration, implemented where slow natural regeneration rates and rapid development of new seismic lines call for silvicultural intervention 28 , is already underway. The current caribou recovery plan for Alberta lists 10,000 km of restored seismic lines as a primary objective in the recovery of declining herds 73 and contemporary research suggests there may be some effect on deer 74 . However, restoration of polygonal features is also needed to return the boreal landscape to one largely lacking sufficient forage suitable for deer range expansion.…”

Multispecies modelling reveals potential for habitat restoration to re‐establish boreal vertebrate community dynamics

“…The key predators of caribou—wolves and bears—co‐occurred frequently with each other and with lynx and coyotes. Co‐occurrence patterns may be driven by direct species interactions (Tattersall et al., 2020a); however, co‐occurrence patterns can also result from other mechanisms (e.g. Blanchet et al., 2020).…”

“…To date, the majority of studies assessing the potential impacts of seismic line restoration on caribou have been simulation‐based (e.g. Serrouya et al., 2020; Spangenberg et al., 2019; Yemshanov et al., 2019), and empirical assessments of restoration effectiveness remain rare (but see Tattersall et al., 2020a).…”

Simultaneous monitoring of vegetation dynamics and wildlife activity with camera traps to assess habitat change

“…Ultimately, monitoring habitat changes should consider intra‐ and inter‐specific biotic interactions as these reflect underlying ecological processes and ecosystem function (Lomov et al., 2009; Torre Cerro & Holloway, 2020). Indeed, observed differences in understory dynamics between sampling strata in our study area have not been associated with noticeable wildlife recovery – caribou, their predators, and competitors have all continued to use seismic lines (Tattersall et al., 2020a,b). The return of species interactions to pre‐seismic line conditions is therefore ongoing.…”