Mt Glorious Day Frog

Population and DistributionTaudactylus diurnus occurred in disjunct populations in three subcoastal mountain ranges (Blackall, Conondale, and D’Aguilar Ranges) in the s.e. Qld region from Coonoon Gibber Ck in the north to Mt Glorious in the south (Czechura & Ingram 1990; Hines et al. 1999). The area of occurrence of the species is about 1000 km2 (map in Hines et al. 1999). Taudactylus diurnus occurred over a relatively narrow altitudinal range of 350-800 m with most records falling between 500 and 800 m (Czechura & Ingram 1990). In the early 1970’s it was considered to be relatively common where it occurred (McEvoy et al. 1979), but has not been sighted in the wild since 1979 despite continued efforts to relocate the species (Hines et al. 1999). The disappearance of T. diurnus occurred over a period of three to four years: disappearing from the D’Aguilar Range in late 1975, then from the Blackall Range in late 1978 and finally from the Conondale Range in early 1979 (Czechura & Ingram 1990). There is no information on population size, structure, genetics or dynamics (Hines et al. 1999).Formerly known from Kondalilla, Conondale, Mapleton Falls, Obi Obi Gorge, Maiala, and Manorina NP (Tyler 1997), SF 311 and private land (H. Hines pers. comm.).HabitatTaudactylus diurnus was found in montane rainforests, tall open forest, notophyll vine forest and sclerophyll fern forest in association with permanent and temporary watercourses (Czechura & Ingram 1990). In addition, they were also found along watercourses in pure stands of the palm Archontophoenix cunninghamia, in exposed areas, in gorges, in dense non-forest riparian vegetation (Lomandra longifolia, Carex neuroclamys, Elastostems reticulatum and Blechnum nudum) and where the riparian vegetation has been slightly infested with Lantana camara (Czechura & Ingram 1990). Permanent streams with rocky substrates were favoured, but T. diurnus also occurred in permanent and ephemeral streams on gravel, clay, sand and soil substrates (Czechura & Ingram 1990).

ReproductionActive frogs have been observed all year round, although less frequently during winter months (Czechura & Ingram 1990). Breeding occurred in warm weather after or during heavy rain from late Oct. to May, with a Jan.-Mar. peak (Czechura & Ingram 1990; Meyer et al. 2001). Gravid females have been reported between Nov. and May (Straughan & Lee 1966). Amplexus is inguinal and 24-36 eggs (2.2mm diameter) are deposited in gelatinous clumps under rocks or branches in the water (Liem & Hosmer 1973; Watson and Martin 1973; Czechura & Ingram 1990; Meyer et al. 2001). Tadpoles, illustrated by Liem and Hosmer (1973) and Watson and Martin (1973), were found throughout the year.FeedingStraughan & Lee (1966) analysed gut contents and showed these frogs to be opportunistic feeders of invertebrates from the forest floor. Amphipods, hymenopterans and lepidopteran larvae were the most commonly recorded prey in their sample. Frogs have been observed in the wild taking small insects along or near streams (Czechura & Ingram 1990). There have been no observations to suggest that prey is taken from the water (Czechura & Ingram 1990).Invasive speciesTaudactylus diurnus was not found in areas along watercourses that were heavily infested with Lantana camara or where the weeds Baccharis halimifilia and Agertina riparia (mist flower) occurred (Czechura & Ingram 1990). The frogs were also absent from streams with very muddy water associated with the activities of feral pigs (Czechura & Ingram 1990).MovementsTaudactylus diurnus were stream dwelling and stream breeding frogs that were active during the day, with peak activity occurring at full light and rapidly declining towards the evening, though some individuals will occasionally move about until the late evening (Ingram 1980). The species was usually found in and along watercourses in low vegetation and leaf-litter or basking on rocks within 10 m of a water source (Czechura & Ingram 1990). The greatest distance that any individual was recorded away from a watercourse was about 22 m and this occurred in wet weather (Czechura & Ingram 1990). The species remains close to the water because it is fairly intolerant of dry conditions and it must frequently enter the water (swimming or sitting half-submerged) to rehydrate (Czechura & Ingram 1990). At night individuals have been located in rock crevices, under stones at the water’s edge, under debris, in fallen palm fronds, in old burrows or clinging to broad leafed riparian vegetation (Czechura & Ingram 1990).

The reason(s) for the disappearance of T. diurnus remains unknown. Like Rheobatrachus silus, logging has occurred in catchments occupied by T. diurnus (Hines et al. 1999), however the effect of timber harvesting on the species has not been investigated. The species habitat is currently threatened by feral pigs, invasion of weed species (especially mist flower) and altered stream flow and water quality due to upstream disturbances (Hines et al. 1999).