christy morrissey is also finding high levels of wetland contamination. she focuses her research in canada's breadbasket, the prairie pothole region of saskatchewan, where agricultural land is laced with potholes, small temporary ponds fed by snowmelt and rain. >> in 2013 we found up to 90% of the ponds that we sampled in spring, even before the farmers were out seeding, had detectable levels of neonics in them. but our peak concentrations occurred after seeding, not surprising, particularly after rainfall events, at levels that were, you know, upwards of, uh, 3 parts per billion, which is well known to affect aquatic insects. >> with over 40% of the cropland in canada's prairies treated with neonicotinoids, the impact on aquatic insects and the animals that rely on them for food could be significant. dr. morrissey's study is the first to look into this issue in canada. >> we have a field study that's trying to understand how neonicotinoids potentially get into wetlands and whether or not they affect aquatic invertebrates, which are the base of the food c