Abstract

The Mitchell’s Satyr Butterfly (MSB) is a critically endangered butterfly with a disjunct range: living in Michigan, Mississippi, and Alabama. The butterfly faces extinction as small, fragmented northern populations struggle to adapt to extreme temperatures and other threats. The introduction of butterflies from larger, healthier southern populations to northern populations is under consideration by various management stakeholders. Introductions help struggling populations by introducing new, heritable (encoded in DNA) traits, reducing inbreeding and increasing population size. An underappreciated benefit is that new DNA variation also enhances evolutionary capacity by providing the necessary genetic material for adaptation to future challenges. I will pair genomic data with laboratory experiments on heat and cold tolerance to proactively identify DNA variations most likely to benefit northern populations. I will also identify the northern populations most at risk (i.e.- highly inbred), and southern populations with new genetic variants, broad thermal tolerance, and ability to interbreed with northern individuals. This will increase the probability that introductions enhance population sizes and, more importantly,help northern populations adapt in the future, ensuring the long-term survival of MSB. This is the first gnomically informed intervention for an endangered insect. Thus, this research creates a road map that can be incorporated into USFWS species’ recovery plans for the many endangered species facing similar challenges.