Attempted introduction of the endangered Green and Golden Bell Frog to Long Reef Golf Course: A step towards recovery

The Green and Golden Bell Frog Litoria aurea is threatened with extinction, but generally occurs in disturbed sites and has successfully colonized some sites that are essentially artificial. It should therefore be possible to promote recovery of the species by increasing the availability of suitable habitat through habitat modification or creation and, where necessary, translocating individuals into these habitat areas. Apparently suitable habitat for this species had been created at Long Reef Golf Course in the northern Sydney suburb of Collaroy. We translocated approximately 9,000 captive-bred tadpoles from Taronga Zoo into these habitat areas over 7 years. This program has not led to the establishment of a self-sustaining population of the Green and Golden Bell Frog at Long Reef Golf Course and must therefore be considered unsuccessful. It has had partial success as some released tadpoles metamorphosed into frogs, some of these developed into adults, and a few males were recorded calling. However, breeding by these introduced animals has not been recorded, and, in the absence of continuing tadpole releases, the number of bell frogs has declined to zero. It has, however, provided a number of guidelines for future similar programs. Success with this program has been limited by fish, time of tadpole release and water temperature, and hence we recommend that future translocations of Green and Golden Bell Frog tadpoles should be carried out during spring or summer and should target ponds that are warm and fish-free. Program success was also limited by the numbers of tadpoles available for release. The lack of tadpoles for spring/summer release since the 2003/2004 breeding season has prevented evaluation of new, relatively warm ponds. Any captive-breeding program for this frog species must therefore be successful, in its own right, if it is to provide tadpoles for release. Disease is unlikely to have influenced the outcomes of this program, but should always be considered a potentially-important factor.