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Black Garden Ants

Lasius Niger (Black Garden Ant)
Black garden ant queens are approximately 15mm long and mid brown in colour. Worker ants are 3.5 - 5mm long and dark brown.
Black garden ants prefer sweet tasting foods and can often be seen during the summer months foraging for food. Although not particularly a health hazard they are a nuisance pest if they enter a home looking for food or have nested in a property.
Ants mate ‘on the wing’ and flying ants may be male or immature females. Once queens have mated they will land, discard their wings and find a place to tunnel. The males will die off after a day or two.
Once she has dug her new tunnel she will seal the entrance and stay at the bottom constructing a small chamber where she lays her first eggs. Until these mature she will not eat.
The ants have four stages of development, egg, larvae pupae and adult. During this time they are fed by either the queen or in an established colony the worker ants.

The workers will forage for food and bring it back to the nest to feed the developing ants and the rest of the colony. They feed on the garden on a sweet sticky secretion from aphids and greenfly. In a house they will be attracted to sweet food. They leave a pheromone trail showing the other workers the way to the food source.

A colony with a good food source will grow quickly and can reach numbers of 15,000 but 4,000 to 7,000 ants is more common. A queen can live for up to 12 years.