Bull ants are dangerous to some people. Every sting hurts, and healthdirect's ant stings and bites page says bull ant stings sometimes cause anaphylaxis, the most severe kind of allergic reaction. The jack jumper, a smaller black bull ant, is the bigger risk: the Australasian Society of Clinical Immunology and Allergy (ASCIA) names it as the major cause of anaphylaxis from ant stings in Australia. For someone who is allergic, a sting is a medical emergency.
What happens when a bull ant stings?
Bull ants sting rather than bite. The Australian Museum's bull ants page describes how it happens: the ant grips the skin with its jaws, curls its abdomen under and drives in the sting at the tip, often more than once. ASCIA notes that, unlike bees, bull ants rarely leave the sting behind in the skin.
healthdirect describes three levels of reaction:
- Local reaction. Pain, redness, itching and a hot feeling, with swelling usually less than 5 cm across that lasts under a day.
- Large local reaction. Swelling wider than 10 cm, sometimes with blisters, that lasts at least 24 hours and can take 7 to 10 days to clear. healthdirect says allergic reactions are more common in children than adults.
- Severe whole body reaction. Swelling of the throat, a hoarse voice, wheezing, chest pain, dizziness, severe stomach pain or vomiting. This is anaphylaxis.
For suspected anaphylaxis, healthdirect's instruction is to use the adrenaline autoinjector immediately, then call triple zero (000) for an ambulance and follow an ASCIA action plan if the person has one. It also says to see a doctor after a sting in the mouth or near the eyes, or if the person has had a serious reaction to an ant sting before.
How do you tell a bull ant from a jack jumper?
Both belong to the genus Myrmecia. The Australian Museum counts about 90 bull ant species in Australia, with nine recorded in Sydney so far. The large ones grow up to 40 mm, with big eyes, long slender jaws and often red or orange on the head or abdomen. Their eyesight is sharp enough to track a person from about a metre away.
Jack jumpers are smaller. ASCIA's jack jumper ant allergy page puts them at 10 to 15 mm, with a black body and orange or brown jaws and legs, while the larger bull dog ants run 15 to 25 mm. The giveaway is the way they move. Jack jumpers make jerky, jumping movements toward you instead of simply running, and ASCIA lists the coastal regions of New South Wales among the places they live.
Engadine borders the Royal National Park, and the Australian Museum lists urban areas, forest, woodland and heath as bull ant habitat. An Engadine family that finds large red and black ants following them across the back lawn toward the bush fence should book ant control in Engadine and show the technician where the ants come and go.
Where do bull ants nest around a house?
Underground, and usually out of sight. The Australian Museum says bull ant nests often have small or hidden entrances and can run several metres below the surface. ASCIA adds that jack jumper nests are often hard to find. They may sit under rocks, with the entrance ringed by a pile of fine gravel and a couple of sentry ants waiting at the hole.
Around a home, that points to soil under something solid, such as rocks, garden edging, pavers and the base of retaining walls.
Loftus sits beside the Royal National Park. A Loftus yard with sandstone rocks along the back fence, where big ants pour out from under one rock whenever the lawn nearby is mowed, needs ant control in Loftus before someone runs the mower past it again.
ASCIA also says jack jumpers often stray long distances and can find their way into houses and kitchens. Woronora Heights is bounded by the Woronora River on the west and the top of the escarpment on the north. A Woronora Heights household that keeps finding single black ants with orange legs on the kitchen floor should arrange urgent ant control in Woronora Heights, since those are the markings of a jack jumper.
Why does a nest near the back step matter?
Because repeat stings carry their own risk. In areas where jack jumpers live, ASCIA says surveys have found 2 to 3 per cent of people have had a generalised allergic reaction to their stings. Around 70 per cent of people with jack jumper allergy will react again if they are stung again, and that sensitivity can last for many years. ASCIA also notes that common bull ants have been known to cause anaphylaxis.
ASCIA advises having nearby ant, bee or wasp nests removed by professionals, especially where allergic children spend time. At home, that means the back step, the path to the clothesline, the sandpit and any spot people cross barefoot every day.
Yarrawarrah was known as North Engadine until it was named in 1971, and it borders the Royal National Park. A Yarrawarrah family whose child has already reacted badly to an ant sting, with a nest now open beside the path to the clothesline, should book an ant control service in Yarrawarrah rather than wait for the next sting.
Do not dig, flood or spray the nest yourself. The Australian Museum says bull ants attack intruders of any size that come near the nest and often sting several times, and whatever is poured into the entrance is unlikely to reach a nest several metres deep.
Before you book
Note these details so the technician can find the nest quickly:
- where you see the ants most, and whether it is near a step, path, clothesline or play area
- their size and colour, and whether they hop or jump toward you
- any rocks, edging or pavers they come out from under
- whether single ants are turning up inside the house
- whether anyone at home has reacted badly to an ant, bee or wasp sting before
Send those details when you contact our team for pest control across the Sutherland Shire: call Sutherland Shire Pest Control Pro on 02 8360 3033 or email [email protected].