Investigators

Cole Matson, Baylor University
Thomas Custer, USGS-Midwest Environmental Sciences Center
Christine Custer, USGS-Midwest Environmental Sciences Center

Project Summary

This project will assess chromosomal damage in tree swallow (Tachycineta bicolor) nestlings collected from contaminated areas across the Great Lakes region. These efforts are designed to complement and directly integrate into the existing USGS Great Lakes Restoration Initiative (GLRI) Project 80 - Birds as Indicators of Contaminant Exposure in the Great Lakes. The GLRI project is quantifying exposure to, and some of the effects of, historical and emerging contaminants on Great Lakes food chains using tree swallows as a sentinel indicator species. The project focuses on quantifying exposure to, and uptake of contaminants into tree swallow nestlings as well as the examination of biomarkers of chemical exposures.

This related project makes use of existing and future tree swallow samples from across the Great Lakes region to assess contaminant-induced DNA damage. Specifically, the flow cytometric method (FCM) will be used for quantifying chromosomal damage. This is a method the project team has successfully used to evaluate the impacts of a variety of contaminants on tree swallows and other indicator species.

Environmental chemistry data being collected under the current GLRI efforts will be used to identify correlations between specific contaminant classes and observed chromosomal damage. Preliminary data from tree swallows collected along the Ottawa River from 2010-2012 provide evidence that the proposed methods will be useful in evaluating the effectiveness of dredging and other remediation efforts across the Great Lakes.

It is anticipated that the FCM data produced as part of this project, in conjunction with existing Project 80 data, will contribute directly to assessments of Great Lakes ecosystem health and science-based decision making, prove valuable to states and the Environmental Protection Agency for assessing whether specific beneficial use impairments can be removed and areas of concern (AOCs) subsequently delisted, provide a baseline for future trend analysis, and determine the effectiveness of recent remediation actions at AOCs and other known hotspots. It is also anticipated that this work will be published in the peer-reviewed literature, providing a framework for others to utilize similar methods to better understand the impacts of environmental contamination of wildlife populations and to monitor the effectiveness of remediation efforts.