Bulldog Ants
Australian Bulldog Ants, generally just called bullants are large, aggressive ants found in many parts of Australia.
Bullants perform a similar function to earthworms in improving soil conditions by opening the soil and improving plant growth when they excavate their nests. Ants also play an important role in keeping the forest floor clean by collecting unhealthy, dead and exhausted insects.
Species
Bullants are amongst the most ancient species of ant in the world. Their closest relatives are species found only in fossils!
Bullants (Myrmecia species) have large eyes, long jaws and a prominent sting. They are generally brown, red and/or black and up to about 30mm long. It is very difficult to identify ants to species level.
Distribution
Australia is the home of ants!
Ants live in every part of Australia. In warmer areas there may be as many as 150 species of ants per hectare but even in the colder parts there may be as many as 75 species of ants per hectare.
Home
Bullants make large and usually obvious nest mounds up to one metre across and often decorated with stones and pieces of plant material. A typical nest consists of a number of irregular galleries connected with runways or passages. There may be more than one entrance hole.
If you look very carefully at an antsˇ¦ nest you will be able to see where they dump the soil from excavations, unwanted wastes and even dead ants.
Colonies vary in size from only a few hundred to many thousands of ants.
Every ant in the colony except one is a female. Each ant belongs to a particular caste and has a specific job to do.
Worker ants:
- Dig holes
- Collect food
- Carry out the garbage
- Do the housework.
Soldier ants
- Protect the colony from attack by other ants and many other ant hunters (for example, spiders, wasps, ant-lions, and echidnas)
Queen ant
- Lays all the eggs
- Issues instructions to other ants (worker ants lick the queen for information!)
Male ants
- The only male in the colony
- Mates with the Queen.
Bulldog ants are most active during the warmer months. During the winter the Ants are not very active and move deeper into the ground. In summer they avoid the dry part of the day and are largely active at night, while in the warm wetter parts of the year they can be seen during the day.
Territories
If the nest is disturbed the Bull Ants will pour out and attack any foreign objects near their nests, but sometimes other insects, often very small species ants, will move in with the ants, sharing their comfortable nest.
Breeding
When a Queen starts a nest she digs a small chamber to lay her eggs in. There is one Queen ant that lays all the eggs and one or only a few male that is just there to mate with the Queen. The Queen ant may live for several years in fact, as many as 10 years or more!
The ant's life cycle passes through egg, larva, pupa and adult phases. Almost every ant is born female. The eggs hatch into small grubs, which grow into worker ants. These adult worker ants make the nest bigger. As more ants are born and become adult workers, the nest becomes larger.
Feeding
Ants eat a wide range of foods collected from the area surrounding the nest. At night they can be found climbing very tall trees to gather food. Ants can carry over 100 times their own weight, which is very helpful when collecting food.
Their diet includes:
- small insects
- honeydew from insects
- seeds
- fruit
- fungi
- gums
- nectar.
When the forager ants return to the nest, they will regurgitate fluid food to feed to larvae and other members of the colony.
Some food is stored in chambers and galleries in the nest for future use.
And did you know ants even have their own dairies. They actually feed on sugar (honeydew) from sap sucking bugs like aphids; just like milking cows!
Adult Bullants, despite their aggressive nature and looks, eat nectar and honeydew! However the larval ants are carnivores, they eat insects brought to them by the adults; that's another use for their huge jaws!
Interesting facts
Bullants stings hurt so much because they inject formic acid into the sting! They use their large jaws to grab hold of you and then use their stinger to inject the formic acid.
Ants secrete a special chemical that kills pollen so, unlike most insects that are attracted to flowers, ants play no role in pollination. Scientists are testing this secretion to see if it can be used to treat human diseases.
Behaviours
When watching an ants' nest, it is very difficult to select an individual ant so just go with the main activity you notice.
No activity:
There are no ants moving around the ants' nest.
Walking with food:
Several ants are walking through the nest carrying pieces of food such as small insects. They may also be carrying dead Bullants or bits of plant material out of the nest.
Walking without food:
Several ants are walking around the nest but are not carrying food items.
Emerging from ant nest:
Several ants are emerging from the hole at the top of the ants' nest.
Fighting/defending:
Ants are engaged in fighting off an unwanted visitor such as Echidnas, other ant species, wasps and spiders.
Grooming:
Ants will spend time cleaning their antennae and legs .
Information sources
Anderson, A (1991) The Ants of Australia: A Guide to the Bassian Fauna (1981) Australian Insects 2, Australian Wildlife Series, Bay Books, Sydney.
Brunet, Bert, 2000, Australian Insects: A Natural History, Reed New Holland, Sydney.
Daniell, A., 2002 Melbourne Wildlife Sanctuary
McKeown, Keith C., 1944, Australian Insects: An Introductory Handbook, Royal Zoological Society of New South Wales, Sydney.
New, T.R. (1996) Name That Insect: A Guide to the Insects of Southeastern Australia, Oxford University Press, Melbourne.