Data from: American marten and fisher do not segregate in space and time during winter in a mixed-forest system

Understanding the mechanisms of coexistence between ecologically similar
species is an important issue in ecology. Carnivore coexistence may be
facilitated by spatial segregation, temporal avoidance, and differential
habitat selection. American martens Martes americana and fishers Pekania
pennanti are medium‐sized mustelids that occur sympatrically across
portions of North America, yet mechanisms of coexistence between the two
species are not fully understood. We assessed spatial and temporal
partitioning in martens and fishers in the Upper Peninsula of Michigan,
USA, using camera trap data collected during winter 2013–2015. To
investigate spatial segregation, we used a dynamic occupancy model to
estimate species’ occupancy probabilities and probabilities of persistence
and colonization as a function of covariates and yearly occupancy
probability for the other species. Temporal segregation was assessed by
estimating diel activity overlap between species. We found weak evidence
of spatial or temporal niche partitioning of martens and fishers. There
was high overlap in forest cover selection, and both marten and fisher
occupancy were positively correlated with deciduous forests (excluding
aspen [Populus tremuloides]). There was strong temporal overlap
(equation/ece35097-math-0001.png; CI = 0.79–0.82) with both species
exhibiting largely crepuscular activity patterns. Co‐occurrence of martens
and fishers appears to be facilitated by mechanisms not investigated in
this study, such as partitioning of snow features or diet. Our results add
additional insights into resource partitioning of mesocarnivores, but
further research is required to enhance our understanding of mechanisms
that facilitate marten and fisher coexistence.