Rapid Adaptation and Conservation

Recent work has demonstrated that adaptive evolution often occurs on contemporary time scales (years to decades), making it of particular relevance to conservation planning (Ashley et al. 2003; Stockwell et al. 2003). Reports of rapid evolution span a variety of species, traits, and situations, suggesting that rapid adaptation is the norm rather than the exception (Hendry & Kinnison 1999; Kinnison & Hendry 2001; Stockwell et al. 2003). Furthermore, rapid adaptation is often associated with the same anthropogenic factors responsible for the current extinction crisis, including overharvest, habitat degradation, habitat fragmentation, and exotic species (Stockwell et al. 2003) and thus has immediate relevance to conservation biology. Here, we briefly consider the potential importance of rapid adaptation to the conservation of actively managed species and to the spread and control of exotic species. Rapid adaptation is of particular concern for captive populations (i.e., “domestication;” Fleming & Gross 1993; Frankham 1995; Margan et al. 1998) as well as for “refuge” populations established as a hedge against extinction (Stockwell & Weeks 1999). Such actively managed populations may rapidly diverge from their parental populations to the point that they are maladapted to their ancestral habitat. Similarly, recent genetic models suggest that augmentation of native populations from captive stock (“supportive breeding”) will likely reduce a wild population’s fitness (Lynch & O’Hely 2001; Tufto 2001; Ford 2002). It is also possible that selection pressures may change and thus limit the success of repatriation programs. For instance, natural selection at release sites may be so strong that populations go extinct even in the process of adapting to the “new” environment (Lynch 1996). One solution would be to introduce populations to intermediate environments. Another approach may be to “select” phenotypes most likely to succeed in the new environment (Hendry et al. 2003).These observations suggest that adaptive responses should be a major consideration for actively managed species.