Temporal changes in avian community composition in lowland conifer habitats at the southern edge of the boreal zone in the Adirondack Park, NY

PLoS One 14(8): e0220927

Michale Glennon, Stephen Langdon, Madeleine Rubenstein, & Molly Cross

Climate change represents one of the most significant threats to human and wildlife commu- nities on the planet. Populations at range margins or transitions between biomes can be par- ticularly instructive for observing changes in biological communities that may be driven by climate change. Avian communities in lowland boreal habitats in the Adirondack Park, located at the North American boreal-temperate ecotone, have been the focus of long-term monitoring efforts since 2007. By documenting long-term changes in community structure and composition, such datasets provide an opportunity to understand how boreal species are responding differently to climate change, and which habitat characteristics may be best able to retain boreal avian communities. We examined three specific questions in order to address how well current biological communities in Adirondack boreal wetland habitats are being maintained in a changing climate: (1) how do trends in occupancy vary across spe- cies, and what guilds or characteristics are associated with increasing or decreasing occu- pancy? (2) how is avian community composition changing differently across sites, and (3) what distinguishes sites which are retaining boreal birds to a higher degree than other sites? Our analysis revealed that (1) boreal species appear to exhibit the largest changes in occu- pancy among our study locations as compared to the larger avian community, (2) dynamics of community change are not uniform across sites and habitat structure may play an impor- tant role in driving observed changes, and (3) the particular characteristics of large open peatlands may allow them to serve as refugia for boreal species in the context of climate change.