Pest Profile

Ants

Ants are the most common pest call we take. They march through kitchens, bathrooms, and pantries in numbers that make it look like the floor is moving. Killing the ones you can see does almost nothing. The colony is somewhere you can’t reach, and until that nest is dealt with, the trail comes back.

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Ants in the Top End

Australia has a very high diversity of ant species. Many of these turn up in Top End homes at some point.

The species you are most likely to encounter in a Darwin home is the Coastal Brown Ant. They are small, light to mid-brown, and they love water. You will find them around kitchen sinks, bathtubs, kettles, dishwashers, and under potted plants. They build nests in soil, wall cavities, sub-floors, and pavement cracks, and they send long foraging trails across hard surfaces toward food and moisture.

Other species commonly found in Australian homes include Bull Ants, Garden Ants, Argentine Ants, Pavement Ants, Black House Ants, Ghost Ants, and Pharaoh Ants. Most of what we treat in Darwin homes is Coastal Brown.

Ant Species

Ants you'll see around Darwin

If you are unsure what species you have, take a close-up photo and send it to us. Species ID matters because the right treatment depends on it.

Coastal Brown Ant

Small (about 2 to 3 mm), light to mid-brown, often seen in long single-file trails on benchtops, walls, and floor edges.

Singapore Ants

About 1.8-3 mm, dark brown/red. Forms long trails along walls, floors electrical equipment 

Black House Ant

About 2-3 mm, black, attracted to sweet foods. Common in wall cavities, paths and gardens.

Ghost Ant

About (1.3-1.5 mm). Tiny with transparent abdomen hard to see against light surfaces. Often nest deep in wall cavities and split into multiple colonies when disturbed. Found in wet areas in homes.

Green Ants

About (5-10 mm).  Green abdomen with orange body. Habitat garden area in trees, shrubs. Build a nest by pulling leaves together. They bite. Problem ant for gardeners.

Warning Signs

Signs of Ant Activity

Trails

Long lines of ants moving in both directions between a food or water source and a nest.

Nests

Small piles of fine soil/sand around pavement cracks, garden edges, retaining walls, or sub-floor vents.

Winged ants indoors

Reproductive flights happen seasonally. If you see flying ants inside, especially after rain, the nest is likely close. Note: flying termite reproductives can look similar; if you are unsure, do not disturb the activity and call us first.

Persistent return after spraying

If you have already sprayed the trail and the ants are back within a day or two, you are dealing with the symptom, not the colony.

Frass and debris

Bits of soil, dead ants, and discarded wing fragments around skirting boards, window frames, or wall cracks.

Action Plan

What to do if you have ants

1

Don't blanket-spray the trail

Surface sprays kill the ants you can see and trigger the colony to send more foragers from a different angle. They do not solve the problem.

2

Note where the trail enters and exits

That tells us where the nest is likely to be. A photo of the trail and the entry point speeds up species ID and treatment planning.

3

Book a treatment

We treat the nest, not just the trail. On our package treatments we include a 3-month ant-free service period as standard.

Service Pricing

Northern Rock Can Help

Cockroaches, Ants & Spiders

3 or 4 Bedroom Home. Full treatment for cockroaches, ants & webbing spiders.
Darwin / Palmerston From
$295

Rural areas may incur a small additional travel and access charge. Remote areas require a custom quote.

Cockroaches, Ants & Spiders

2 Bedroom Home. Full treatment for cockroaches, ants & webbing spiders.
Darwin / Palmerston From
$270

Rural areas may incur a small additional travel and access charge. Remote areas require a custom quote.

Senior & Defence Discount

10% discount for Senior Card holders and verified Defence members on standard pest treatments and termite inspections.

Questions

Common questions about ants around Darwin and the Top End.

Surface sprays only target the individual foraging ants you can see, leaving the colony and queen unharmed. Many ant species respond to chemical sprays by fragmenting the colony, which often makes the infestation spread and become more difficult to manage. Professional treatments focus on eliminating the nest itself.
While both can swarm, termites typically have straight antennae, equal-length wings, and a broad, thick waist. In contrast, ants have distinctively bent (elbowed) antennae, unequal-length wings, and a pinched, thin waist. If you are unsure, do not disturb the insects, as misidentified termites can pose a significant structural risk.
At Northern Rock, our standard package treatments include a 3-month ant-free service period. If ant activity returns inside this window, we will return to re-treat the affected area at no additional cost.
Ants in the Top End are primarily drawn to moisture rather than food. Kitchen sinks, taps, kettles, dishwashers, and leaking pipes are major attractants. While removing food residue and drying surfaces helps, it will not eliminate the colony, which is usually located outside the building.
Unlike termites, ants do not consume timber for food. They nest in wall cavities, sub-floor spaces, and voids because the environment suits their needs. However, they can still damage electrical appliances, wiring insulation, switches, and air conditioning units. Professional treatment is generally far more cost-effective than repairing this secondary damage.
Yes. We prioritise the use of family-safe and pet-safe products, which are applied specifically to bait points and trail areas rather than broadcast spraying. Your technician will provide a clear re-entry window (typically a few hours) to ensure the treatment is completely dry before family members or pets access the area.

Ant problems?

Top End conditions favour ants year-round: warmth, humidity, and seasonal moisture flushes that drive colonies indoors. Most Darwin homes will have ant pressure at some point regardless of how clean the kitchen is.