Rebuilding endangered species using a stepping-stone model for reintroduction
Captive breeding programs are intended to rebuild highly endangered populations, but a major problem is how to reintroduce captive-bred individuals back to their native habitat. Often, there is low survival of reintroduced individuals compared to wild-born individuals. Such is the case for the critically endangered Vancouver Island marmot, which had shrunk to just 30 individuals in 2003. A new experiment compares survival to breeding age for three strategies: transferring wild-born individuals, translocating captive-born individuals to wild habitat, and a new stepping stone strategy that involved first transplanting captive born individuals to a safe wild area with high survival before transferring them in their second year to the lower-survival final destination. While the highest success is from transferring wild individuals to new areas, the stepping-stone approach was estimated with 83% certain to have higher probability of reaching prime breeding age than the straight-to-wild individuals. The new results, coauthored by SAFS professor Sarah Converse and new SAFS postdoc Nathan Hostetter, appear in the journal Animal Conservation.
