Wetland Restoration for the Threatened Green and Golden Bell Frog (Litoria aurea): Development of a Breeding Habitat Designed to Passively Manage Chytrid-Induced Amphibian Disease and Exotic Fish

Abstract

Amphibians are under threat from many drivers resulting in declining populations. Restoration and creation of habitat is a method used to reverse amphibian declines. The green and golden bell frog (Litoria aurea) is distributed in southeastern Australia, and is threatened by the fungal pathogen Batrachochytrium dendobatidis (chytrid), an introduced fish (the plague minnow, Gambusia holbrooki), and habitat loss. There have been numerous wetland restoration attempts to combat population declines in this species, which have been largely unsuccessful in producing persisting populations. Here we present a robust model for the creation of breeding habitat for the L. aurea population on Kooragang Island, New South Wales, which is based off thorough review of the literature and past pilot studies and experiments. We describe in detail the habitat, land use history, and wetland habitat design formulation and construction so that the context of the habitat creation is understood and so construction can be repeatable and the design can be further refined. The habitat features passive controls for chytrid and G. holbrooki, and contains the most optimum breeding habitat for L. aurea based upon current knowledge. This is the first attempt in our knowledge to create wetlands in an open system that have the potential to passively manage chytrid.