A21 · Ants
Red Imported Fire Ant
Solenopsis invicta
A notifiable biosecurity pest. Do NOT treat yourself — report sightings to the National Fire Ant Eradication Program.
- Size
- 2–6 mm (workers vary in size)
- Habitat
- Open sunny ground — lawns, paddocks, road edges, disturbed soil
- Activity
- Year-round, most active in warm months
Safety Warning
Report fire ant sightings to the National Fire Ant Eradication Program on 13 25 23 (or online at fireants.org.au). In NSW call 1800 680 244. Sightings are confidential and free to report. Allergic reactions to stings (swelling of face/throat, difficulty breathing) require calling 000 immediately.
Overview
Red Imported Fire Ants (RIFA) are one of the world's worst invasive species and a major threat to Australian agriculture, environment and lifestyle. Currently being eradicated from South East Queensland. They build dome-shaped mounds of loose soil (up to 40 cm high) with no obvious entry hole on top — ants enter via underground tunnels. They swarm aggressively when disturbed and deliver a painful burning sting that can cause severe allergic reactions. DIY treatment is illegal in restricted zones and disturbing a nest can split the colony, making the problem far worse.
How to identify
- Coppery-brown body with a darker abdomen, 2–6 mm
- Workers vary noticeably in size within the same nest (unusual for ants)
- Loose, fluffy dome-shaped mound of soil with NO central entry hole
- Aggressive swarming response within seconds of the mound being disturbed
- Painful sting leaves a small white pustule 24–48 hours later
General guidance only. Information on Home Pest Defence is provided for educational purposes and is not a substitute for professional advice. For termites, venomous spider bites, wasp nests in walls, or protected wildlife, contact a licensed pest controller, your GP, or the relevant state wildlife authority. In emergencies call 000; for poisoning call 13 11 26.