Carnivore use of parturition habitat
We hypothesized that the use of predicted parturition habitat by actively-searching predators would track the phenology of the birth pulse such that they would use areas that maximized encounters with neonates when they were most available. Of the species concluded to exhibit active search for neonates (cougars and bears responding to elk calves), linear mixed-models suggested that only male bears followed the expected quadratic pattern for use of parturition habitat coincident with peak parturition date (βJulian week = 0.027,P = 0.03; βJulian week2 = -0.028, P = 0.03; Figure 6b) wherein the quadratic terms were supported over a linear term (likelihood ratio test, P = 0.03) for the effect of Julian week on use of calving habitat. To assess whether this result could be spuriously driven by bears selecting for parturition habitat for other reasons such as bottom-up forage acquisition, we tested whether female bears with similar vegetation requirements as male bears also responded to parturition habitat but found no support for a quadratic response (likelihood ratio test,P = 0.62; Figure 6c). For cougars, use of predicted parturition habitat was also better explained by a linear term for Julian week (likelihood ratio test P = 0.32; Figure 6d).