Caterpillars defoliate the Pee Dee

According to climate data, coastal North and South Carolina were having a mild drought in mid May of 2011. Mean water flow for the Pee Dee River near Pee Dee, SC during the 24-days prior to May 16 was 15.9% below the 2003-2010 average for that time according to USGS statistics (http://waterdata.usgs.gov). These clues suggest that this reduction along the Waccama and Pee Dee Rivers of the Carolinas is not the result of flooding. Aerial detection surveys conducted that same month agree, as most of these anomalies were attributed to defoliation by forest tent caterpillars which are frequent visitors in spring.