Where motivations, metrics, and milestones meet: A comprehensive framework for assessing and planning reintroductions

Background/Question/Methods

Species reintroductions – the release of captured or captive-bred organisms into areas within their historic range that they no longer occupy – are an increasingly common tool in conservation, growing exponentially in the past century.  Despite accompanying growth in reintroduction-related research and scientific guidance, reintroductions still face a variety of challenges.  In order to aid reintroduction planning, execution, and assessment, we develop a novel, interdisciplinary framework for gauging reintroduction progress and outcomes.  Moving away from current problems in defining reintroduction success, we illustrate how population ecology provides a model for population growth and identify key ecological phases and sequential milestones reintroduced populations may achieve.  Building on existing planning strategies and stakeholder processes used in other conservation areas, we identify how stakeholder motivations may impact the desired ecological endpoints for reintroduced organisms.  Recognizing the uncertainty commonly associated with reintroductions, we show how the framework allows ecological and non-ecological (societal and financial) goals to be clearly associated with metrics and subsequently matched to ecological milestones throughout the reintroduction process.

Results/Conclusions

This comprehensive framework offers a standard base for considering reintroduction programs.  Ecological milestones provide a common backdrop for any organism upon which reintroduction goals can be placed.  Connecting ecological and non-ecological goals to clear metrics offers a method to address some of the largest hurdles (e.g., funding, public support, financial impacts) reintroductions often face and encourages transparency regarding desired outcomes.  This also supports adaptive management strategies by accounting for uncertainty that may exist in reintroduction planning and moving away from strict density or abundance goals.  As a result, this stakeholder-driven perspective may aid in identifying shared goals among groups or points of conflict.  Overall, the framework adds clarity to discussion of reintroductions by moving beyond post-hoc analyses of failure or success and can aid in both the practice of reintroductions and large-scale analysis of reintroduction trends.