Francis Lemckert

Overview of the conservation status of Australian frogs

A review of the current conservation status of Australian amphibians was recently completed as part of a World Conservation Union (IUCN) sponsored Global Amphibian Assessment (GAA). Fifty of 216 amphibian species (23%) in Australia are now recognized as threatened or extinct in accord with IUCN Red List Categories and Criteria. Here we report on the categories and criteria under which individual species qualified for listing and provide a summary of supporting information pertaining to population and distribution declines. Major threatening processes contributing to listing of species are also reviewed.

The influence of micrometeorological factors on the calling activity of the frog Crinia signifera (Anura: Myobatrachidae)

I recorded the calling activity of the males of a population of the common eastern froglet Crinia signifera during 1988 to determine the seasonal and temporal patterns of calling activity and the influence of micrometeorological variables on calling. The patterns of calling were recorded using an automated cassette recorder switched on for 10 seconds approximately every 15 minutes. To assess the effects of micrometeorology on calling I compared the mean hourly calling activity with air temperature, barometric pressure, humidity, rainfall and wind intensity with time of day as a co-variable. This comparison was undertaken for data from three separate two-month periods of the year, as well as with the data from the three periods combined, to determine if there were seasonal differences in the effects of micrometeorology. For the analysis I used a forward stepwise Generalised Linear Model. Chorusing was recorded in every month of the year. Time of day was highly significant as a predictor of hourly calling a...

A survey for threatened herpetofauna of the south-west slopes of New South Wales

Timber production forests and adjacent lands of the south-west slopes New South Wales were surveyed tor frogs and reptiles over three periods during 1994/95. Hand and aural surveys targeted the habitats of eight endangered species known from or considered likely to occur within the region. Eleven species of frog and eighteen species of reptile were located during the survey. but only one of these was a listed threatened species (with another being recorded incidentally after the survey period). However, the presence of suitable habitat indicated that four other threatened species could be present in the area. It is suggested that continued habitat alteration through gazing and agricultural practices may be having the greatest impact on the herpetotauna of the area and hat a suitable reserve system is required incorporating known a likely sites for each species. It is recommended that grazing should be phased out of some state forest areas and burning regimes modified to provide a diversity of habitats.

Two hundred and ten years looking for the Giant Burrowing Frog

The giant burrowing frog Heleioporus australiacus (Shaw) is a large, morphologically distinctive, but cryptic frog found in south eastern Australia. This paper reviews the literature pertaining to ...

Spatial ecology of the giant burrowing frog (Heleioporus australiacus): implications for conservation prescriptions

Management of threatened anurans requires an understanding of a species’ behaviour and habitat requirements in both the breeding and non-breeding environments. The giant burrowing frog (Heleioporus australiacus) is a threatened species in south-eastern Australia. Little is known about its habitat requirements, creating difficulties in developing management strategies for the species. We radio-tracked 33 individual H. australiacus in order to determine their habitat use and behaviour. Data from 33 frogs followed for between 5 and 599 days show that individuals spend little time near (<15 m) their breeding sites (mean 4.7 days for males and 6.3 days for females annually). Most time is spent in distinct non-breeding activity areas 20–250 m from the breeding sites. Activity areas of females were further from the breeding site (mean 143 m) than those of males (mean 99 m), but were not significantly different in size (overall mean 500 m2; males 553 m2; females 307 m2). Within activity areas, each frog used 1–14 burrows repeatedly, which we term home burrows. Existing prescriptions are inappropriate for this species and we propose protection of key populations in the landscape as a more appropriate means of protecting this species.

Parasitism of the Common Eastern Froglet Crinia signifera by flies of the genus Batrachomyia (Diptera: Chloropidae): Parasitism rates and the influence on frog condition

The presence of Batrachomyia larvae was recorded on 13 19 frogs captured in pitfall traps as part of a study on the population ecology of the Common Eastern Froglet Crinia signifera breeding at a pond at Darkes Foresf New South Wales.The body length. body mass and reproductive status of each frog captured were also recorded to compare the physical state of parasitised frogs with unparasitised frogs. Nineteen females and eleven males were recorded with parasites.The body condition (lengthlmass) of parasitised males was significantly less than for unparasitised males, but was not significantly different for female frogs. Females with parasites had a lower mean condition than unparasitised females, but the greater body size of females appears t o reduce the relative effect of the parasite. Fifteen of the parasitised female frogs had oviducal eggs and three were known to have subsequently laid eggs. Hence larvae do not suppress the reproduction of the host frog.

Correlations between frogs and pond attributes in central New South Wales, Australia: What makes a good pond?

We assessed if certain attributes of human created ponds in a forest environment make them more favourable for use by frogs. We recorded 24 habitat variables associated with 45 ponds in a forested area of central New South Wales and compared these with counts of frogs at the ponds. We used Canonical Correspondence Analysis (CCA) to explore which variables influenced community structure and Generalised Linear Modelling techniques to determine the variables influencing the total numbers of frogs and/or species using the ponds. We also used Zero Inflated Poisson modelling to assess which variables influenced the presence and abundance of individual species. We recorded 24 species, but only nine used a third or more of the ponds. CCA indicated that our measured variables had little influence on community structure and species did not cluster into regular associations. Species richness was significantly, but only weakly related to the measured variables, which displayed little explanatory value. Variables that significantly influenced the presence and/or abundance of individual species varied widely, but depth was most often important for the former and bank and emergent vegetation for the latter. Predicting a pond type that benefits a select group of species is not possible, but pond types beneficial to some species were identified. The results suggest that we can construct or modify ponds in forests to benefit selected species, but a range of ponds are required to benefit permanent pond breeding species.

Non-breeding habitat requirements of the giant burrowing frog, Heleioporus australiacus (Anura: Myobatrachidae) in south-eastern Australia

Non-breeding habitats are an important, yet poorly understood component of the habitat requirements of most frog species. As a result, non-breeding habitats may be poorly protected and their loss m...

Short-term movements and habitat use by the threatened Green-thighed Frog Litoria brevipalmata (Anura: Hylidae) in mid-coastal New South Wales

Miniature radio-transmitters were used to follow 13 Green-thighed Frogs for between one and five nights around their breeding ponds during the postbreeding period. Individuals were recorded to move a median distance of 5 metres per night with a maximum of 50 metres in one night. All tracked individuals remained within the available areas of forest. Frogs located at night were found in low vegetation 59% of the time, at heights between 10 cm and 150 cm above the ground. Daytime shelter sites were either under leaf litter or in thick vegetation. Cover, in the form of thick leaf litter or dense low vegetation, may be a critical requirement for the survival of the Greenthighed Frog.

Living in the 80s - seasonality and phenology of frog calling activity at Darkes Forest from 1987-1989

We recorded the calling activity of frogs at a permanent pond 80 km south of Sydney between 1987 and 1989, documenting the calling seasons of five species and relating calling activity (within calling seasons) to temperature, humidity, barometric pressure and rainfall. Three species commenced calling in August/September with Litoria peronli and Uperokia laevigata calling consistently throughout the summer months and Umnodynastes dumerilil calling more sporadically. Limnodynastes peronii appeared capable of calling at any time of the year, but did not call continuously. Litoria verreauxii called very consistently from January to September. Random effects models indicated that the probability of males calling increases with increasing temperatures in Limnodynastes peronli, Litoria peronii and Uperoleia laevigata. Increasing barometric pressure was positively associated with calling in Umnodynastes peronii. Calling was not related to either rainfall or humidity for any species. The calling seasons were similar to expectations based on published information. The lack of relationships between calling and rainfall and humidity may be related to the presence of permanent water and or the regular rainfall experienced throughout the study period. Historical data from this study may provide a baseline for future studies to assess changes in calling phenology linked to climate change.