Balancing foraging opportunity and predation risk: influence of dependent neonates on spatial co-occurrence of northern cervids and omnivorous predators

For female ungulates, the vulnerability of neonates can lead to trade-offs between predation and access to forage. We explored the spatial overlap between moose ( Alces americanus (Clinton, 1822)), deer ( Odocoileus hemionus (Rafinesque, 1817), O. virginianus (Zimmermann, 1780)), elk ( Cervus canadensis Erxleben, 1777), grizzly bear ( Ursus arctos Linnaeus, 1758), and black bear ( U. americanus Pallas, 1780) during parturition (15 May to 28 June) and after the parturition period (29 June to 30 October). We used camera images collected at 66 sites between 2020 and 2021 to parameterize integrated multi-species occupancy models. Covariates measured at the scale of the camera and grid cell were useful for assessing detection and occupancy of the six focal species, respectively. For both reproductive periods, occupancy models representing human disturbance (e.g., road density, cutblock size) explained detection while occurrence was explained by habitat composition (e.g., elevation, basal area, canopy closure). Grizzly bears, elk, and deer occupied similar low-elevation areas during the parturition period, supporting the foraging hypothesis. Consistent with the predator avoidance hypothesis, elk occupied habitats with forest structure that would reduce detection by predators during the post-parturition season. Although results represented the coarse-scale distribution of sympatric prey and omnivorous predators, ungulates with young likely experienced a trade-off between accessing high-quality forage and minimizing predation from bears.