pengilleyi prefers to breed in sphagnum bogs and wet heath in sub-alpine areas and dense patches of herbs in openings or seepages amongst fallen tussocks at lower elevation (bog pools at high altitudes above and in shallow seepage pools in gullies at lower altitudes of ). Other reproductive details are as for P. corroboree. Both species are restricted to mountain and sub-alpine woodlands, heathlands and grasslands. Non-breeding habitat for both species occurs in forest, woodland and heath adjacent to breeding sites. Diet The typical diet of a mature southern corroboree frog includes beetles, mites, ants and insect larvae. However, as tadpoles they also tend to eat algae and other small pieces of organic material found in their pools. Toxicity Corroboree frogs are the first vertebrates discovered that are able to produce their own poisonous alkaloid, as opposed to obtaining it via diet as many other frogs do. The alkaloid is secreted from the skin as a defence against predation, and potentially against skin infections by microbes. It has been described as potentially lethal to mammals if ingested. The unique alkaloid produced has been named pseudo-phrynamine. Behaviour Corroboree frogs are quite unusual in their nature. Not only do they not start breeding until four years of age, they also hibernate during winter under whatever shelter they can find. This may be snow gum trees, or bits of bark or fallen leaves. Males stay with the egg nests and may breed with many females over the course of one season. Conservation status The southern corroboree frog was considered relatively numerous within its very small distribution in the 1970s, as of June 2004 it had an estimated adult population of 64, but suffered declines of up to 80% over the 10 years up to 1989, at which time it was found only within a fragmented region of less than within Kosciuszko National Park. It has been listed as critically endangered since at least 2004 and is considered to be one of Australia's most endangered species. There are fewer than 30 individuals left in the wild . The northern corroboree frog has not suffered as badly as the southern. It is more widely distributed across about of the Brindabella and Fiery Ranges in Namadgi National Park in the ACT, and Kosciuszko National Park and Buccleuch State Forest in NSW. In 2004 it was downgraded from an IUCN assessment of critical to endangered. Cause for