ESA Annual Meetings Online Program
Putting the canary back in the coal mine: Crickets and ants in the saltmarshes post-Macondo blowout
Sunday, November 11, 2012: 4:45 PM
200 D, Floor Two (Knoxville Convention Center)
Our research has shown that insects and spiders are good bioindicators of environmental pollution from catastrophic oil spills. Even when environmental toxicologists are unable to measure volatiles in samples of the oil pollution, we observed impacts that indicated that volatiles were active on insects and spiders during times when the marsh sediment was exposed to insolation and bacterial degradation. We conducted a ‘common garden’ experiment also known as an in situ bioassay where we placed insects in floating cages 20m from the streamside edge of oiled and unoiled saltwater marshes. Seventeen months post-spill, insects in cages in oiled marshes exhibited a greater mortality than those in unoiled reference marshes indicating that volatile compounds, possibly from the emulsion, plays a role in insect/spider mortality in oiled marshes. In spill season 1 (2010), ant abundance had decreased by 66% in oiled marshes when compared to reference marshes. By September 2011 or spill season 2, ants in oiled areas had decreased by 97%. In 2012, we were unable to find mature ant colonies in heavily oiled areas and found more than 50 colonies in similar unoiled areas. Only incipient colonies were found in oiled areas in April and May 2012.