Adaptive management and climate change impacts for the endangered Karner Blue butterfly
Endangered species management is often subject to uncertainty, due to the inherently limited scope of studies and the level of protection surrounding the species. The statistical validity of experiments can be diminished by limited population sizes, while efforts to protect the species often conflict with the potential benefits of studying their dynamics. The scale and timing of ecological change command immediate management solutions, limiting the ability to gather adequate information about the organism’s biological and ecological functions. Adaptive management addresses this issue by essentially using a feedback loop, where newly gained knowledge about species is continuously fed into an evolving management practice. Accordingly, how can land managers use biological and ecological dynamics towards adaptive management on an imperiled organism?
The Karner Blue butterfly (Lycaeides melissa sameulis, KBB) is a federally endangered species living in highly fragmented, sandy glacial outwash plains within the Great Lakes and northeastern US regions. Its distribution is restricted to the range of its larval host plant, wild blue lupine (L. perennis). As a specialist and endangered species, the KBB is susceptible to changes in habitat and climate. In this study, we aim to determine how climate change affects KBB development and directly inform future management practices.
We explored KBB’s climate change sensitivity and adaptive capacity by pursing a diversity of experiments on several life stages (egg, larvae, pupae, adult).
First, we pursued a climate warming scenario experiment to determine how the KBB growth rate and development is affected by climate change. Individuals in the warmer treatments experienced less time spent in developmental stages, shorter life spans, and decreased adult weight. Second, we investigated how temperature affects KBB flight by measuring activity rate from 12 – 45 °C. Males exhibited lower tolerance for high temperatures, while females had a higher tolerance for extreme temperatures. We identified an optimal temperature for flight at 24 – 30 °C. Third, we studied when diapause is induced by subjecting individuals to short day (8 hours light: 16 dark) (SD) and long day (16:8) (LD) photoperiods during different life stages. Preliminary results reveal that the individuals exposed to LD-SD hatch treatment (LD until hatch and SD for rest of life) produced the most diapause-induced eggs, as opposed to eggs that immediately hatched.
We find that actively communicating our findings on a regular basis to the KBB National Recovery Team aides in both developing adaptive management strategies and informing next steps in research.