Move at-risk species to locations that are expected to provide habitat

The climate may be changing more rapidly than some species can migrate, and the movement of species may be restricted by land use or other impediments between areas of suitable habitat. Fragmentation of habitat and physical barriers in urban areas may make this even more challenging, especially for rare or threatened species. Species-rescue assisted migration, focused on avoiding extinction by physically relocating climate-threatened species, may be an option to consider in some cases. This approach is best implemented with great caution, incorporating due consideration of the uncertainties inherent in climate change, the sparse record of previous examples, and continued uncertainties of forest response.

Urban areas already contain a broad mixture of species that come from outside of the area. Because these species evolved in different climates, they will probably have very different tolerances to future climate conditions. In the urban landscape, fostering species transitions is less a question of whether to assist migration of species from other geographies; this is already a common occurrence. Instead, it is more about deciding when and where to incorporate species into forests and plantings in different habitats and land uses. These species could be nonnative taxa or species that are regionally native, that is, those from the same region but not currently growing at that particular location. In addition to increasing the climatic resilience of the urban landscape, urban forests could also facilitate the migration of species that will be favored under future climate to new habitats at or beyond the edges of their current range.