Canada lynx occurrence and forest management in the Acadian Forest

Abstract

We evaluated patterns of occurrence and non‐occurrence for Canada lynx (Lynx canadensis) across a 16,530‐km2 study area in Maine to provide a better understanding of lynx habitat selection and habitat ecology on commercially managed forestlands in the Acadian Forest. Because of the influence of forest structure on lynx habitat selection and abundance of their primary prey, the snowshoe hare (Lepus americanus), and to improve our ability to build robust models, we used habitat information derived from a time series of Landsat satellite imagery spanning the period 1973–2004. We defined and mapped 10 forest types based on forest harvest history, time since harvest, and current forest condition. We compared a suite of models to evaluate relative influences of forest composition, habitat patch configuration, and hare density on habitat selection by lynx at the landscape scale. Occupied areas had greater average hare densities and percentage of mature conifer. Average hare density in occupied areas (0.74 hares/ha) was greater than in unoccupied areas (0.62 hares/ha), but was less than previous research has suggested may be necessary to support lynx populations in the southern portion of the species' range. No occupied areas occurred where average hare density was <0.5 hares/ha. Average hare density at the landscape‐scale was strongly influenced by amount of high‐quality hare habitat (i.e., conifer or mixedwood regenerating forest, 15–35 yr post‐harvest). Edge density between mature conifer and high‐quality hare habitat was substantially greater in occupied areas compared to unoccupied areas. Juxtaposition of those 2 forest types may provide edge habitat where lynx experience easier travel and improved access to prey in landscapes with extensive areas of high‐quality hare habitat where travel and access may be somewhat limited by high understory stem density. Probability of occurrence declined nonlinearly with changes in hare density and percent mature conifer forest in the landscape; thus, suitability of currently occupied landscapes could change markedly with future changes in landscape‐level hare densities and changing habitat associated with forest management. Where lynx conservation is a priority, we recommend that managers focus on creating and maintaining a minimum of 27% high‐quality hare habitat within 100‐km2 areas to promote landscape‐scale hare densities >0.5 hares/ha. © The Wildlife Society, 2013

Habitat monitoring and projections for Canada lynx: linking the Landsat archive with carnivore occurrence and prey density

“…Simons‐Legaard et al . () constructed a priori candidate models to evaluate alternative hypotheses about lynx occurrence and (i) amount of high‐quality hare habitat (HQHH), which was defined as 15‐ to 35‐year‐old, conifer or mixed wood forest; (ii) configuration of HQHH; or (iii) average snowshoe hare density. Models were parameterized using occupied and unoccupied home ranges simulated from empirical presence/absence data recorded during systematic snow track surveys within our study area.…”

“…2004 (Simons‐Legaard et al . ). Using the time series as the basis for extrapolation allowed us to seamlessly evaluate retrospective changes in habitat extent and distribution (1973–2004), update predictions with newer imagery (2004–2010) and predict future patterns in distribution of foraging habitat for lynx (2010–2022).…”

Assessing cumulative impacts of forest development on the abundance and distribution of furbearers.

“…In general, lynx distribution is highly correlated with their primary prey species, snowshoe hare (Apps 2000, Poole 2003, Hoving et al 2004, Simons-Legaard et al 2013). …”

“…Although many researchers would agree that lynx populations depend heavily on the availability of prey (Apps 2000, Poole 2003, Hoving et al 2004, Simons-Legaard et al 2013), the link between lynx populations and the availability and quality of habitat is not well quantified. Habitat for their primary prey species, snowshoe hare (Lepus americanus), is often associated with regenerating forests that occur following logging or wildfire (Mowat et al 2000, Poole 2003, Simons-Legaard et al 2013).…”

“…Habitat for their primary prey species, snowshoe hare (Lepus americanus), is often associated with regenerating forests that occur following logging or wildfire (Mowat et al 2000, Poole 2003, Simons-Legaard et al 2013). Consequently, both snowshoe hare and lynx populations may benefit from landscape disturbance Slough 2003, Hoving et al 2004).…”