Hierarchical structure of Canada lynx space use and habitat selection in northeastern Minnesota

Limited knowledge about the ecology of the Canada lynx (Lynx canadensis) in the United States (U.S.), particularly its habitat requirements, resulted in the species being listed under the U.S. Endangered Species Act. I used global positioning system (GPS) collars to study the use of space and the habitat selection of 12 (6 males, 4 breeding females, and 2 non-breeding females) Canada lynx in northeastern Minnesota, U.S. over time periods that reflect the presence of snow or lynx reproductive biology. Male home ranges (range = 29-522 km2) and core areas (range = 6-190 km2) were usually larger than the home ranges (range = 5-95 km2) and core areas (range = 1-19 km2) of females. The smaller home ranges of females were less sensitive to sample size than those of males. I used the space-use estimates to evaluate habitat selection with two habitat use metrics: (1) movement paths collected while following lynx trails with hand-held GPS units, and (2) locations recorded by the GPS collars worn by lynx. I modeled lynx habitat selection for both use metrics with 3 hierarchical spatial comparisons that represented areas used by lynx with different intensities. Lynx consistently selected for 10-30 year-old successional forests, and sites where lynx foraged or rested were more common there. Lynx showed less selection for these forests in the intensively used core areas because successional forest was more abundant in core areas. Although successional forest is important for lynx in Minnesota, lynx also responded to the distribution of mature forests. Most lynx consistently selected against mature lowland-conifer forests, but female lynx with 3-7 month-old kittens used these forests in proportion to their availability. Lynx also selected for the edges between patches of mature upland-conifer forest and successional forest, likely because these edges allowed for easier travel or more efficient foraging for snowshoe hares (Lepus americanus). Forest management to benefit lynx populations should consider using timber-cutting patterns that intersperse patches of 10-30 year old successional and mature conifer forests, which may mimic the patterns that resulted from the fires that historically controlled regeneration in boreal forests.