Animal Species:Bull ants
Bull ants have a fearsome reputation, and deservedly so.
Bull Ant on top of its nest
J.Green
© J.Green
Alternative Name/s
Bulldog ants
Number of species
90
Identification
Bull ants are large, alert ants that can grow up to 40 mm They have characteristic large eyes and long, slender mandibles and a potent venom-loaded sting. They have superior vision, able to track and even follow intruders from a distance of 1 metre. Many species of bull ants have bright red or orange colours on the head or abdomen.
There are about 90 species of bull ants in Australia with diverse behaviours and life cycles. Nine bull ant species have been recorded in Sydney, but there may be more as yet undiscovered. Some of the smaller species are known as jumper ants after their habit of aggressively jumping toward intruders.
Size range
8 mm - 40 mm
Distribution
Bull ants are found throughout Australia.
Habitat
Bull ants live in urban areas, forests and woodland, and heath.
Feeding and Diet
Bull ants collect nectar and other plant juices, as well as animal prey, which are carried back to the nest.
Other behaviours and adaptations
Bull ant nests are usually underground and often have hidden or small entrances. The nests can extend several metres below the ground. They attack intruders of any size that come too close to their nest. Bull ants also have well-developed vision and will follow or even chase an intruder a good distance from the nest. Usually the sight of large aggressive ants streaming out of the nest is enough to prompt a hasty retreat. If not, the ants deliver painful stings by gripping the intruder with their mandibles (jaws), curling their abdomen to reveal the sting and injecting the victim with venom. Often multiple stings are delivered.
Life cycle
Several species have no colony workers. Instead, a raiding queen invades the nest of another species, kills the resident queen and takes over the colony.
Danger to humans and first aid
These ants can deliver painful stings and are aggressive. An ice pack or commercially available spray may be used to relieve the pain of the sting. If there is evidence of an allergic reaction, medical attention should be sought.
Classification
- Genus:
- Myrmecia
- Subfamily:
- Myrmeciinae
- Family:
- Formicidae
- Superfamily:
- Vespoidea
- Suborder:
- Apocrita
- Order:
- Hymenoptera
- Class:
- Insecta
- Subphylum:
- Uniramia
- Phylum:
- Arthopoda
- Kingdom:
- Animalia
Last Updated:
Tags ants, insects, arthropods, invertebrates, identification, wildlife of sydney, dangerous, bites, stings, myrmecia, stinging, anaphylactic shock, allergic reaction, bull ants, bulldog ants,
28 comments
Dear Nicole,
I would treat it with caution, especially if anyone in the family has a history of allergies to bee, ant and wasp stings, as the stings are similar or worse than a honey bee. A single ant like this may not necessarily mean you have a nest in the vicinity, as some of the larger bull ant species disperse at this time of year, with winged males and females flying out to found new nests. What you have may be one of these rather than a worker from an established nest. If you can see little scars on the top of the middle segments above the legs it may be a reproductive male or female. These are where they shed their wings after the nuptial flight. Workers do not have these scars. If it is a worker, you will have a nest nearby, and it might be good to know where it is so you can tell the kids to stay away from it. I hope this helps.
Hi Markus,
I could not locate a similar species in our collection. Whilst your photo is good, I can't see the characters that would let me key it out to a species group, and even if I did so I think it would be tricky to put it to species. Ogata (1991) has a key in his review of species groups in the genus Myrmecia (Systematic Entomology, 16:353-381) if you want to try for yourself. Good luck!
http://anic.ento.csiro.au/ants/biota_details.aspx?biotaid=37361 has detail on the genus Myrmecia
In regards to collecting and identifying ants, you cannot go past Steve Shattuck's book "Australian Ants" from CSIRO Publishing. Much of the identification and other resources available inthis book are also available from the website What Bug is That? http://anic.ento.csiro.au/insectfamilies/
This one looks like Myrmecia nigrocincta, a common species along the coast. Like some other smaller Myrmecia it has the "jumping jack" behaviour when threatened or disturbed. This species seems to prefer arboreal foraging to being on the ground, and is often seen on the leaves of trees.
In regards to the maximum size of bull ants:
The largest specimen in the Australian Museum collection is a queen of Myrmecia forficata collected from Oatley in 1952. She measures 33mm in length from tip of gaster to mandible. The size of bull ants within any one nest varies considerably, although queens are always bigger than the workers. Another Museum scientist tells me that he observed workers of a very large species in the Victorian mallee; presumably the queens of this species would exceed 33mm in length.
Dear Nathan,
The larger species of bull ants (eg. Myrmecia gulosa, M. brevinoda, M. forficata) occur in the south of Australia, including Tasmania, so it is not unusual to see one around Sydney. They are not common in urbanised areas as there is usually insufficient areas of natural bush in which they can forage for food. The nests are usually conspicuous raised domes covered in pebbles or small sticks, so if you have one nearby, you should be aware of it and avoid spending too much time nearby, as these ants are aggressive. They do not normally go indoors, but reproductives (males and females) are active during late summer and early autumn, and may be attracted to lights in houses.
Female alate (winged and reproductive) bull ants retain a functional sting, but I would not recommend that as a safe way of determining sex :-).
In general, female alates are much larger than male alates and have a long basal antennal segment (= scape), whilst male alates have a short scape.