Invasive toads in Australia could be turned against each other to control the population.

Richard Shine at the University of Sydney in Australia and his colleagues grew cane toad (Rhinella marina) tadpoles and embryos together in containers in the laboratory, and separated them with a mesh partition. They found that the tadpoles suppressed embryo growth by 33–84% and reduced their survival to less than 5%.

The tadpoles seem to produce a chemical that blocks embryo growth, allowing them to outcompete the embryos. The practice of removing tadpoles from breeding ponds could actually boost the growth of embryos; instead, tadpoles could be kept in mesh containers in the pond to stymie the embryos' growth, the authors say.

J. Appl. Ecol. (2015)