The medaka that were in the mesocosms treated with imidacloprid were all, absolutely all 100 percent of the fish, were contaminated with protozoan parasites.
When the lab-reared medaka laid their eggs on strips of vegetation, the researchers took the plants out of the water for between zero and 24 hours—at conditions favourable to the unhatched eggs—before returning them.
In a new paper in Science of Nature, Mr Yao and his colleagues report that the medaka eggs can successfully hatch after enduring up to 18 hours out of the water attached to a plant leaf.