Red-eared terrapin: Application of a biocide
Overall effectiveness category Unlikely to be beneficial
Number of studies: 1
Background information and definitions
Biocides such as glyphosate may negatively impact red-eared terrapin Trachemys scripta populations, by reducing hatching success of the eggs of breeding populations.
Supporting evidence from individual studies
A replicated, controlled laboratory study in 2005 in the USA (Sparling et al. 2006)found that application of glyphosate to the eggs of red-eared terrapins Trachemys scripta elegans reduced hatching success and the health of hatchlings, but only at the highest glyphosate concentration. Hatching success at the highest concentration of 11,206 ppm wet weight of glyphosate in Glypro and 678 ppm of the surface active agent LI700 was 73%, compared to hatching success of 80-100% in the lower concentrations and the control. Hatchlings from eggs that had been exposed to the highest concentration of glyphosate and surface active agent also weighed less both at hatching and at the end of the holding period, compared to those from eggs that had been exposed to lower concentrations. Eggs of red-eared terrapins were exposed to single applications of glyphosate and surface active agent, ranging from 0 to 11,206 ppm wet weight of glyphosate in Glypro and 0 to 678 ppm of the surface active agent LI700.Study and other actions tested