As we approached the dam where this shot was taken the sound of calling frogs became deafening. There were frogs in the water, in the trees and even sitting on the old fence post as in the picture. This male and female Litoria peronii or Emerald Spotted Treefrogs are part of a population being studied on the south coast of NSW. The research is looking at the interaction between sperm and eggs and whether there is the potential for eggs to choose sperm from different males.