Giant Dragonfly, NSW Southern Highlands, Australia.
Scientific name: (Petalura gigantea)
Conservation status in NSW: Endangered
The Giant Dragonfly is the third largest dragonfly in Australia and one of the largest dragonflies in the world. Males have an abdomen length of 6 – 7.5 cm, a wingspan up to 11 cm and petal-shaped claspers at the end of the abdomen. Females have an abdomen length of 8 – 9.5 cm and a wingspan up to 12.5 cm, and no claspers. The larvae are also very large, up to 5 cm in length.
The Giant Dragonfly is found along the east coast of NSW from the Victorian border to northern NSW. It is not found west of the Great Dividing Range. There are known occurrences in the Blue Mountains and Southern Highlands, in the Clarence River catchment, and on a few coastal swamps from north of Grafton to Nadgee in the south.
Habitat and ecology
• Live in permanent swamps and bogs with some free water and open vegetation.
• Adults spend most of their time settled on low vegetation on or adjacent to the swamp
• Adults fly over the swamp and along its margins hunting for flying insects.
• Females lay eggs into moss, under other soft groundlayer vegetation, and into moist litter and humic soils, often associated with groundwater seepage areas within appropriate swamp and bog habitats. The species does not utilise areas of standing water wetland, although it may utilise suitable boggy areas adjacent to open water wetlands.
• Larvae are slow growing and the larval stage may last up to 10 years.
• Development activities, such as mining for gypsum or other forms of mineral extraction
• Climate change
• Loss or modification of natural swamps
• Changes in natural water flows.
• Decreasing water quality of swamps through pollution and siltation.
• Application of pesticides on or adjacent to swamps.
• Weed invasion
• Damage to habitat by feral pigs.
• Changes to natural water flows as a result of groundwater extraction.
• Changes to natural fire regimes.
• Clearing and development of land.
What needs to be done to recover this species?
• Retain or reintroduce natural water flows to swamp habitats.
• Protect swamps from pollution.
• Minimise the use of pesticides in and adjacent to swamps.
• Protect natural swamps from modification and disturbance.