

Photo of an Eastern Red Bat
Image Credit:  Aimee Haskew, 2007




Map of Hydrogen Isotope Gradient Across North America
Taking advantage of the gradient in stable hydrogen isotope ratios (δ2H) in precipitation across North America, we were able to identify potential summering regions of individuals by comparing the hydrogen isotopes in the bat hair samples to hydrogen isotopes in rainfall. The variation δ2H in precipitation is incorporated into hair keratin through drinking water and diet. This incorporation occurs during summer when temperate bats undergo their annual molt, making it possible to infer where bats are summering. Image credit:;

A Novel Approach


This work aims to address two key questions:





Location map of study area


Stable Isotope Analysis


Conceptual diagram illustrating origins of bats killed at turbine sitesPopulation Genetics



Likelihood-of-origin maps for two different hoary bats
Representative likelihood-of-origin maps like the two shown above for two different hoary bats were generated for each individual sampled. Red areas indicate the highest likelihood of origin for each particular individual while blue areas indicate lowest likelihood of origin. The map for the individual shown on the left suggests that the bat was local, which is indicated by the red at the sampling locations. The individual pictured in the map on the right was most likely to have summered elsewhere, which is suggested by the red bands located further north and the blue areas at the sampling locations.
Diagram illustrating how to understand STRUCTURE plots
Understanding STRUCTURE output plots: Shown are three different output plots from STRUCTURE, which was used to analyze the population structure from the genetics results. The top two diagrams depict the genetic structure of the different bat species from this study (L. cinereus and L. borealis). Each individual is represented by a single vertical line. The results from the bat work suggest that there are no distinct genetic populations among the two bat species. Conversely, the bottom diagram depicts the genetic structure of a population of brook trout (Salvelinus fontinalis) sampled in western Maryland that does have genetic structure (Kazyak et. al 2016).

Future Work


AL Principal Investigators:

David Nelson, J. Edward Gates, Matt Fitzpatrick