Exposure to the weedkiller glyphosate is making feral cane toads more toxic and negatively impacting other species in Australia.Hungarian scientists reported their findings in The Royal Society last week.
Scientists say they fear Australian feral cane toads could become even more toxic, due to the wide variety of habitats on offer, and the amount of pollutants and pesticides our cane toads are exposed to.
“Our results indicate that pesticide pollution might exacerbate the problem of invasive toxic species,” author of the study Veronika Bokony said.
“For example, in Australia, the survival of native tadpoles is reduced by poisoning from ingestion of toxic cane toad eggs, and predators suffer drastic mortality due to ingesting or mouthing cane toads.”
Results showed that all of the exposed tadpoles produced significantly more amounts of bufadienolides (the toxic steroids used by as toads, snakes, and certain plants) after being exposed to Glyphogan for between nine days and three weeks.
The cane toad is an invasive species in Australia. Cane toads are native to South America, and were first introduced to Australia from Hawaii in June 1935 by Sugar Research Australia in an attempt to control the native grey-backed cane beetle and Frenchi beetle, which damaged crops. See this BBC News report for more background.