Southern corroboree frog

The **southern corroboree frog** (_Pseudophryne corroboree_) is one of two species of **corroboree frog** (_Pseudophryne pengilleyi_). The other is the northern corroboree frog. The southern corroboree frog is a very small frog with warning colouration. It has black and yellow stripes, sometimes with a greenish tinge. It is one of the brightest frogs in the world.

It only lives in an area of about  in the Kosciusko National Park in south east Australia. Scientists believe that the total population of corroboree frogs is less than 250. Numbers of the frog have reduced by 80% in the last ten years, and so the International Union for Conservation of Nature and Natural Resources (IUCN) have listed the southern corroboree frog as being a critically endangered species.

## Habitat

The southern corroboree frog live in a small area in the Kosciusko National Park. It usually lives in Snow Gum forest, and Sphagnum swamps. These places are very cold, because the Corroboree Frog only lives in areas higher than 1000m above sea level. The corroboree frogs  breed in small ponds and wetlands during the summer months.

## Physical description

The southern corroboree frog has a very distinctive pattern of black with bright yellow stripes. They are very small, only around  long when fully grown. The female frog is usually larger than the male and can be as big as  They mainly eat bugs, like ants, beetles and mites. They have a very different breeding cycle to most other frogs. Most frogs breed in spring, but these frogs only breed in summer during January and February. They use the wet areas to dig small holes for their mating and nesting. They lay between 16-40 eggs. The eggs hatch 4–6 months later when water levels rise and flood the nests. The frogs live as tadpoles for another 6–8 months. They change into frogs at the start of summer in December. They become sexually active after another two years. The frogs are not known to survive a second breeding season.

### Toxicity

Corroboree frogs are the first vertebrates discovered that are able to make their own poisonous alkaloid, pseudo-phrynamine. Most other frogs get it from their diet. The alkaloid is secreted from the skin as a defence against predators, and perhaps against skin infections by microbes.

## Conservation

The southern corroboree frog is Australia’s most endangered frog. Scientists have not discovered a reason for the reduction in frog numbers. There are a range of problems that affect the area that they live in. Increased access by people with four-wheel drive vehicles and the development of ski resorts are destroying their habitat. Global warming is also a big problem for them, because they are used to the cold. Global warming may shorten the frog's breeding time during winter, and also destroy their snowy habitat. Holes in the ozone layer may also be a problem, because when there are holes in the ozone it means that more sun rays hit the ground, and so there is less snow. Disease from funguses can kill lots of the frogs. Erosion and pollution of waterways in which they breed can kill the frogs' eggs. They are also affected by wild pigs which destroy the wetlands.

The NSW National Parks and Wildlife Service are now breeding the frogs in laboratories, and then releasing them into the wild when they are fully grown. After the bushfires in the summer of 2002 and 2003 all the eggs in the wild were collected and taken to the Melbourne Zoo for hatching.