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

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Approach

EASTERN:
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 (Davis and Shaw 2001, Iverson et al. 2004a). This can be particularly challenging for species that are already rare or threatened. Another subset of assisted migration, sometimes called species-rescue assisted migration, focuses on avoiding extinction of species threatened by climate change (Pedlar et al. 2012). If current habitat occupied by those species is expected to become (or already is) unsuitable, assisted migration to potential new suitable habitat may be the best option to ensure survival of the species (Vitt et al. 2010). Because such species are often extremely rare, this type of assisted migration can also potentially cause declines in the donor populations through removal of seeds or individuals (Aubin et al. 2011). 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 (Ricciardi and Simberloff 2009). (1)

WESTERN:
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 (Davis and Shaw 2001, Iverson et al. 2004, Ackerly et al. 2020). This can be particularly challenging for species that are already rare or threatened. Another subset of assisted migration, sometimes called species rescue assisted migration, focuses on avoiding extinction of species threatened by climate change (Pedlar et al. 2012). If current habitat occupied by those species is expected to become (or already is) unsuitable, assisted migration to potential new suitable habitat may be the best option to ensure survival of the species (Vitt et al. 2010). Because some species are extremely rare, this type of assisted migration can also potentially cause declines in the donor populations through removal of seeds or individuals (Aubin et al. 2011). 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 (Ricciardi and Simberloff 2009). (2)

Tactics

  • Planting or seeding a rare or threatened plant species that is at risk for extinction to a newly suitable habitat outside its current range (i.e., assisted species migration) (1, 2).
  • Assisting the migration of wildlife around barriers (e.g. across large tracts of unsuitable habitat or from low elevations to higher elevations) by trapping and releasing in newly suitable locations (1, 2).
  • Moving plants or animals from a mountaintop to another mountaintop north of their current range (i.e., assisted range expansion) (1, 2).

Strategy Text

Species composition in many forest ecosystems is expected to change as species adapt to a new climate and transition into new communities (Iverson et al. 2004b). This strategy seeks to maintain overall ecosystem function and health by gradually enabling and assisting adaptive transitions of species and communities in suitable locations. This may result in slightly different species assemblages than those present in the current community, or an altogether different community in future decades. This strategy includes aggressive actions to promote ecosystem change rather than an unchanging community or species mix. Many of the approaches in this strategy attempt to mimic natural processes, but may currently be considered unconventional management responses. In particular, some approaches incorporate assisted migration, which remains a challenging and contentious issue (McLachlan et al. 2007, Ricciardi and Simberloff 2009). It is not suggested that managers attempt to introduce new species without thoroughly investigating potential consequences to the native ecosystem (Ricciardi and Simberloff 2009). 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. Outcomes from early efforts to transition communities can be evaluated to provide both information on future opportunities and specific information related to methods and timing.

Citation

1. Swanston, C.W.; Janowiak, M.K.; Brandt, L.A.; Butler, P.R.; Handler, S.D.; Shannon, P.D.; Derby Lewis, A.; Hall, K.; Fahey, R.T.; Scott, L.; Kerber, A.; Miesbauer, J.W.; Darling, L.; 2016. Forest Adaptation Resources: climate change tools and approaches for land managers, 2nd ed. US Department of Agriculture, Forest Service, Northern Research Station. 161 p. http://dx.doi.org/10.2737/NRS-GTR-87-2,
2. Swanston, C.W.; Brandt, L.A.; Butler-Leopold, P.R.; Hall, K.R.; Handler, S.D.; Janowiak, M.K.; Merriam, K.; Meyer,
M.; Molinari, N.; Schmitt, K.M.; Shannon, P.D.; Smith, J.B.; Wuenschel, A.; Ostoja, S.M 2020. Adaptation Strategies
and Approaches for California Forest Ecosystems. USDA California Climate Hub Technical Report CACH-2020-1.
Davis, CA: U.S. Department of Agriculture, Climate Hubs. 65 p.