Managed relocation: Addressing the nexus of climate change, invasive species, and fish and wildlife health
No abstract available.
Report↗
Geology topics
Jessica Hellmann
Publications and source records attributed to Jessica Hellmann.
Range-wide population genomic structure of the Karner blue butterfly, Plebejus (Lycaeides) samuelis
The Karner blue butterfly, Plebejus ( Lycaeides ) samuelis , is an endangered North American climate change-vulnerable species that has undergone substantial historical habitat loss and population decline. To better understand the species' genetic status and support Karner blue conservation, we sampled 116 individuals from 22 localities across the species' geographical range in Wisconsin (WI), Michigan (MI), Indiana (IN), and New York (NY). Using genomic analysis, we found that these samples were divided into three major geographic groups, NY, WI, and MI-IN, with populations in WI and MI-IN each further divided into three subgroups. A high level of inbreeding was revealed by inbreeding coefficients above 10% in almost all populations in our study. However, strong correlation between F ST and geographical distance suggested that genetic divergence between populations increases with distance, such that introducing individuals from more distant populations may be a useful strategy for increasing population-level diversity and preserving the species. We also found that Karner blue populations had lower genetic diversity than closely related species and had more alleles that were present only at low frequencies (<5%) in other species. Some of these alleles may negatively impact individual fitness and may have become prevalent in Karner blue populations due to inbreeding. Finally, analysis of these possibly deleterious alleles in the context of predicted three-dimensional structures of proteins revealed potential molecular mechanisms behind population declines, providing insights for conservation. This rich new range-wide understanding of the species' population genomic structure can contextualize past extirpations and help conserve and even enhance Karner blue genetic diversity.
Indiana, Michigan, Wisconsin↗
Warming experiments test the temperature sensitivity of an endangered butterfly across life history stages
The Karner blue butterfly (Lycaeides melissa samuelis) (hereafter Karner blue) is a federally listed endangered species occurring in disjunct locations within the Midwest and Eastern United States. As a hostplant specialist and an ectotherm, the Karner blue is likely to be susceptible to effects of climate change. We undertook warming experiments to explore the temperature sensitivity of various Karner blue life history stages and traits. Over a two-year period, we exposed all Karner blue life stages to temperature increases of + 2, + 4, and + 6 °C above 1952–1999 mean temperatures. We analyzed the effect of these treatments on life history parameters likely related to fitness and population size, including development time, voltinism, degree-day accumulation, body weight, and morphology. Warming treatments resulted in earlier emergence and accelerated development, leading to additional generations. Warming also increased the number of degree-days accumulated during pre-adult development (i.e., egg hatch to eclosion). Results suggest that Karner blues developed in fewer days, in part, by putting on less mass as temperatures increased. As treatment temperature increased, adult body mass, length, and area decreased and voltinism increased. Females with lower adult mass and smaller body size produced fewer eggs. These results suggest a trade-off between accelerated development and decreased body size with decrease in adult mass and abdominal area being associated with reduced fecundity.
Journal of Insect Conservation↗
Evidence of an extreme weather‐induced phenological mismatch and a local extirpation of the endangered Karner blue butterfly
In 2011, an experiment was undertaken to examine spring synchrony between the endangered Karner blue butterfly ( Lycaeides melissa samuelis ) (Kbb) and its obligate host plant, wild blue lupine ( Lupinus perennis ) at Indiana Dunes National Lakeshore (INDU), where the southernmost population of Kbb occurred at the time of this study. From 2012 to 2014, field‐placed Kbb eggs were observed for larvae hatching in conjunction with observations of lupine emergence in oak savanna habitat. In 2012, 61% of Kbb hatched when <5% of lupine had emerged due to an extreme early spring event as compared to subsequent years where temporal overlap was >15% between Kbb and lupine. Laboratory experiments testing the sensitivity of Kbb hatching to warm temperatures during the winter of 2011–2012 confirmed that Kbb eggs were susceptible to temperature‐induced hatching. In the summer of 2012, second generation Kbb larvae feeding on sun‐exposed lupine had higher mortality due to the heat and drought conditions that resulted in earlier plant senescence. Following 2012, Kbb were no longer observed at INDU. This observation illustrates the pressing need for adaptive management strategies that account for extreme weather events brought on by climate change.
Indiana↗