Coastal Brown Ant
The Coastal Brown Ant, sometimes also called the Big-headed Ant, is an introduced species that is common in urban and agricultural areas. It is the common small brown ant in Brisbane backyards. It occurs throughout the eastern seaboard and at Darwin, Perth and some inland towns.
It usually nests in the ground with nest entrances in the open or under rocks and logs or between pavers. Piles of loose soil are thrown up around nest entrances. It can also nest indoors, in crevices in brickwork, wall cavities, behind skirtings and architraves.
This species does not sting. It can be a nuisance pest in the garden and may enter houses to forage. It has a varied diet but prefers food of animal origin (protein and fats) to sweet foods. However, workers will tend sap-sucking insects for honeydew.
This ant is normally associated with human disturbance but has invaded native bushland in some areas. For example, it has infested monsoonal rainforest patches in the Northern Territory and some coral cays in the Great Barrier Reef. When this occurs the ant can build up to enormous populations and displace native ant species and affect other invertebrates.
This light brown species is dimorphic, with small minor workers (length 1.5-3.0) and larger major workers (length 3.5-4.5 mm) with massive darker heads. There are many native species of Pheidole that closely resemble the Coastal Brown Ant and require specialist identification to tell apart.
Source: Queensland Museum website 2015, http://www.qm.qld.gov.au/
The Australian Bull Ant
There are about 90 species of these bull ants here in Australia and they are as feared in the ant world as they are by humans. Get this; Queen bull ants have been known to walk straight into the nest of another species of ants, kill their Queen ant and take over the colony.
It doesn’t matter how big you are either, they will attack if they need to.
Get too close to one of these ant colonies and they will be streaming out of their nest and literary chasing you. If this happens to you, don’t be embarrassed, just….
They are very aggressive and have extremely painful venomous stings.
Their sizes range from around 8 mm to 40 mm, the one I saw was at least 20 to 25 mm and bordering on the biggest ant I have ever seen.
Whatever you choose to call them, bull ants, bulldog ants, jumper ants, sergeant ants, inch ants or even Mymecia if you want to get all scientific, it matters not; they are big ants and not to be messed with.
Source: Bob In Oz Website 2015, http://www.bobinoz.com/