Assessing the benefits and risks of translocations in changing environments: a genetic perspective

Abstract

Translocations are being increasingly proposed as a way of conserving biodiversity, particularly in the management of threatened and keystone species, with the aims of maintaining biodiversity and ecosystem function under the combined pressures of habitat fragmentation and climate change. Evolutionary genetic considerations should be an important part of translocation strategies, but there is often confusion about concepts and goals. Here, we provide a classification of translocations based on specific genetic goals for both threatened species and ecological restoration, separating targets based on ‘genetic rescue’ of current population fitness from those focused on maintaining adaptive potential. We then provide a framework for assessing the genetic benefits and risks associated with translocations and provide guidelines for managers focused on conserving biodiversity and evolutionary processes. Case studies are developed to illustrate the framework.

Understanding managers’ and scientists’ perspectives on opportunities to achieve more evolutionarily enlightened management in conservation

“…In particular, the messages about the importance of general evolutionary concepts, such as genetic diversity (Hoban et al., 2013; Santamaria & Mendez, 2012; Sgrò et al., 2011; Weeks et al., 2011) and adaptation (Hoffmann & Sgrò, 2011), appear to have reached managers. These general concepts have also received more attention than other concepts within the evolutionary applications literature (Cook & Sgrò, 2017).…”

“…There have been concerns expressed in the literature that managers are reluctant to mix individuals from different populations (e.g., gene pool mixing; Weeks et al., 2011) due to concerns about maladaptation of subsequent generations as a result of outbreeding depression (Frankham et al., 2011). However, the lower importance ascribed to outbreeding depression and the poorer application of the concept to management do not support this being a major concern for managers (Figures 1 and 2).…”

“…Such an approach has been termed evolutionarily enlightened management (Carroll et al., 2014). Recent reviews have suggested a range of conservation management issues that would benefit from more evolutionarily enlightened management, including threatened species management, restoration projects and invasive species management (Frankham, 2010; Smith et al., 2014; Weeks et al., 2011). Recommendations for improved practice often centre on the active management of genetic diversity to maintain resilient populations (Table 1; Hoffmann & Sgrò, 2011; Sgrò et al., 2011; Weeks et al., 2011).…”

“…Recent reviews have suggested a range of conservation management issues that would benefit from more evolutionarily enlightened management, including threatened species management, restoration projects and invasive species management (Frankham, 2010; Smith et al., 2014; Weeks et al., 2011). Recommendations for improved practice often centre on the active management of genetic diversity to maintain resilient populations (Table 1; Hoffmann & Sgrò, 2011; Sgrò et al., 2011; Weeks et al., 2011). While the goal of conserving genetic diversity is widely recognized within international conservation policies, such as the Convention on Biological Diversity, little, if any, specific direction is provided about how management practices need to change (Cook & Sgrò, 2017).…”

Population and genetic outcomes 20 years after reintroducing bobcats (Lynx rufus) to Cumberland Island, Georgia USA

“…2011; Weeks et al. 2011). However, any actions to conserve populations, let alone experiments, often have to be planned carefully for endangered species.…”