Habitat loss is splitting the world’s plant and animal populations into smaller, more isolated fragments. At the same time, many organisms must also withstand rapid and stressful changes to their environment. Combined, these factors can increase extinction risk. A possible escape from extinction is through adaptation. Yet, small populations with low genetic diversity may be unable to adapt in time to keep pace with environmental change. One strategy to mitigate these problems is to move individuals from larger, more resilient populations with higher genetic variation into small, declining populations to induce 'genetic rescue'.
This project will use cutting-edge genomic tools to evaluate the potential for genetic rescue to increase population growth and adaptive potential in the federally endangered Mitchell's satyr butterfly, an iconic species that has rapidly declined in the last few decades. Researchers will first evaluate patterns of genomic variation and inbreeding throughout the entire range of the species, identifying potential recipient and source populations for genetic rescue. Then, researchers will perform controlled crosses of individuals from these populations to confirm the viability of offspring and test differences in thermal tolerance.
The proposed research emerged as a top priority of the US Fish and Wildlife Mitchell’s Satyr Working Group and will directly inform conservation andmanagement in the context of genetic rescue. This work will provide crucial information for successful design and implementation of genetic rescue in Mitchell's satyr butterfly as well as other species that also face high extinction probability due to small population sizes and a rapidly changing climate.