Protected areas in a landscape dominated by logging – A connectivity analysis that integrates varying protection levels with competition–colonization tradeoffs

Conservation planning is challenging in landscapes where reoccurring habitat destruction and subsequent recovery affect metapopulation persistence, because different species respond differently to landscape change. By building on a graph-theoretical modeling framework, we here develop a connectivity model of how varying levels of area protection and unprotected areas predetermined for destruction affect species differently depending on (1) their tradeoff in colonization versus habitat utilization ability and (2) their maximum dispersal ability. We apply our model to 20,000 patches of old pine forest in northern Sweden, which host many threatened species but are scattered in a landscape dominated by intensive forestry. Unprotected mature forests stands predestined for logging are treated as adequate but temporarily available habitat for colonization specialists, whereas the same stands are assumed to, at best, serve only as intermediate stepping-stones for habitat specialists as they disperse between long-standing forests in protected areas. Our results show that the effect of habitat fragmentation on metapopulation persistence differs greatly not only depending on the dispersal distance of a particular species, but also on how well it utilizes habitat patches of different longevity. Such traits are discussed with respect to the spatiotemporal planning of habitat protection. Also, we suggest that the negative impacts of logging on biodiversity may be reduced if forestry practice is adjusted to better account for the ecological values of maturing production stands, through spatially explicit modeling of connectivity and of complementarity in the protection gradient.