Condensation onto the skin as a means for water gain by tree frogs in tropical Australia.

Green tree frogs, Litoria caerulea, in the wet-dry tropics of northern Australia remain active during the dry season with apparently no available water and temperatures that approach their lower critical temperature. We hypothesized that this surprising activity might be because frogs that are cooled during nighttime activity gain water from condensation by returning to a warm, humid tree hollow. We measured the mass gained when a cool frog moved into either a natural or an artificial hollow.