Mercury in Terrestrial Songbirds

Tree swallow


Mercury is not just about fish anymore.


Background on Project

In 2005, the Cristol lab started working on a large field project looking at mercury contamination in terrestrial songbirds along the South River in the Shenandoah Valley, Virginia. Though the river had been thought to be the only system contaminated with mercury, Dan and his students found that songbirds feeding exclusively in the terrestrial ecosystem had mercury levels rivaling those that ate fish directly from the contaminated river. It appeared that the birds with highest mercury were feeding on spiders that also had elevated levels of mercury, despite never interacting with the aquatic environment themselves. This research has been published in Science (read about it here). 

Current Project Goals

After four years of field work on the mercury project, the group has now decided to see exactly how mercury affects terrestrial songbirds in a captive setting. Instead of dosing the birds with high levels of mercury at one time, this is the first experiment to feed songbirds doses of mercury in their food that are comparable to what they would experience in the wild. This dosing experiment is already underway in Williamsburg and will eventually document how three different species of birds deal with low level mercury exposure. In order to apply these findings to a variety of species, the three species chosen represent entirely different foraging and breeding strategies: a granivorous domestic songbird (Zebra finch), an insectivorous native songbird (Carolina wren) and an omnivorous feral songbird (European starling). The project has also benefited from the addition of John Swaddle (one of the founding members of iibbs) and Claire Ramos (a postdoctoral researcher). 

Find out more about people working on this project

Dan Cristol (faculty advisor)

John Swaddle (faculty advisor)

Claire Ramos (postdoctoral researcher)

Sarah Lemelin (master's student, effect of mercury on reproductive success and adrenocortical function)

Catherine Lewis (master's student, effect of mercury on the immune system)

Amanda Bessler (master's student, effect of mercury on cognition)

Kenton Buck (master's student, variation and heritability of avian mercury bioaccumulation)

Jenna Carlson (master's student, Sublethal effects of methylmercury on flight in European Starlings)

Megan Kobiela (master's student, effect of mercury on starvation-predation trade-off in zebra finch)

Ellie Sheridan (undergraduate, effect of mercury on song preference)