Data from: Multi-species genetic connectivity in a terrestrial habitat network

Background: Habitat fragmentation reduces genetic connectivity for
multiple species, yet conservation efforts tend to rely heavily on
single-species connectivity estimates to inform land-use planning. Such
conservation activities may benefit from multi-species connectivity
estimates, which provide a simple and practical means to mitigate the
effects of habitat fragmentation for a larger number of species. To test
the validity of a multi-species connectivity model, we used neutral
microsatellite genetic datasets of Canada lynx (Lynx canadensis), American
marten (Martes americana), fisher (Pekania pennanti), and southern flying
squirrel (Glaucomys volans) to evaluate multi-species genetic connectivity
across Ontario, Canada. Results: We used linear models to compare
node-based estimates of genetic connectivity for each species to
point-based estimates of landscape connectivity (current density) derived
from circuit theory. To our knowledge, we are the first to evaluate
current density as a measure of genetic connectivity. Our results depended
on landscape context: habitat amount was more important than current
density in explaining multi-species genetic connectivity in the northern
part of our study area, where habitat was abundant and fragmentation was
low. In the south however, where fragmentation was prevalent, genetic
connectivity was correlated with current density. Contrary to our
expectations however, locations with a high probability of movement as
reflected by high current density were negatively associated with gene
flow. Subsequent analyses of circuit theory outputs showed that high
current density was also associated with high effective resistance,
underscoring that the presence of pinch points is not necessarily
indicative of gene flow. Conclusions: Overall, our study appears to
provide support for the hypothesis that landscape pattern is important
when habitat amount is low. We also conclude that while current density is
proportional to the probability of movement per unit area, this does not
imply increased gene flow, since high current density tends to be a result
of neighbouring pixels with high cost of movement (e.g., low habitat
amount). In other words, pinch points with high current density appear to
constrict gene flow.