Habitat selection and phenology of the Fiji Tree Frog, Platymantis vitiensis, implications for conservation

Abstract

Macrohabitat and microhabitat preferences of the endemic Fiji Tree Frog Platymantis vitiensis were investigated in Savura near Suva, Viti Levu, Fiji. Twelve sites in three habitat types (primary rain forest, disturbed secondary rain forest, and mahogany plantations) were surveyed from June 2004 to May 2005. The phenology of P. vitiensis was also studied along two permanent transects (adjacent to, and distant from, a stream bank) within the Savura area. Individuals were more abundant in primary rain forest than mahogany plantations and secondary rain forest. Individuals were common along stream banks, perched on riparian plants such as Pandanus, ferns, and Dolicholobium (and usually found 100-200 cm above the ground). Rainfall influenced activity, with fewer individuals observed during intense rainfall events. Adult frogs were more frequently encountered between July and October and gravid females between August and November. Hatchlings were more common during the dry season (May to October), whereas juvenile abundances peaked early in the wet season (November to April). Future surveying and monitoring of P. vitiensis populations should be conducted during March to July, when abundances are greater. The efficiency of rapid surveys can be maximized by subsampling along riparian vegetation, particularly where Pandanus are present.