Name: Odorous House Ant
Latin Name: Tapinoma sessile
Nicknames/common names: Odorous ant, stink ant and, coconut ant
Odorous House ants, also known as the odorous ant, stink ant and coconut ant, are common home invaders in Southern Ontario’s warmer months when they forage for sugary foods or escape their shallow nesting sites after rain. They get their name from the pheromone which smells of rancid coconut that is released when they are alarmed or crushed. Odorous house ants in your home can lead to the contamination of food stores and a lingering reek throughout your property. Healthy colonies of upwards of 100 000 ants can develop quite rapidly in humid and moist conditions, under floorboards and in walls, or in the soil beneath debris and a variety of organic matter. Odorous house ants are also able to relocate rapidly and en masse, quickly budding to establish satellite colonies when the primary nest becomes inhospitable. Removing an odorous ant population can be difficult, and is best left to be coordinated by a licensed pest control technician to prevent a supercolony of say, 100 000 workers, from dividing and establishing satellite nests in several different parts of the property.
How to Identify Odorous House Ants:
Odorous house ants range in colour from golden-brown, dark brown to black. They are small, varying in length from 1/16 to 1/8 inches (1.5–3.2 mm). Their antennae have 12 segments.
Life stages & anatomy
Queens live at least eight months (and probably much longer), workers at least a few months (and show every indication of living as long as queens). Males are bred for the sole purpose of reproduction and appear to live only about a week.
The queens lay eggs and incubate them for between 11-26 days. The larva stage then lasts between 13-29 days, and the pre-pupal and pupal stages last between 10-24 days, resulting in a 1-2 month life cycle.
Signs of an Odorous House Ant Infestation
Beyond the signalling of an infestation by the very presence of ants, Odorous House ants release a pheromone which smells of rancid coconuts when they are alarmed or crushed.
Where did they come from / how did I get them?
Odorous ant colonies are polygynous, in that they can contain hundreds of reproducing queens, and polydomous, in that a supercolony will readily divide across multiple satellite nests. A thriving colony will typically overwinter in a single nest, and when food resources are more abundant in the summer, they will form multiple nests. They have even been found to move their nests as often as every three weeks in response to changing food sources; this is called ‘dispersed central-place foraging’. Adaptive and resourceful, odorous ants can live in a wide variety of habitats and express the same eusocial tendencies as many cooperative ant species that have a clear division of labour. They are also tough. Queens have been found to survive without food or water for months, they are highly tolerant to both heat and cold and seem to have an exceptional threshold for pain. Fatally injured workers and queens have been observed to continue to labour, be it foraging or laying eggs, with little hindrance.
Able to form colonies virtually anywhere and in a variety of conditions, when they invade your home Odorous House ants can often be found near sources of heat and moisture, in wall insulation, in house plants, beneath leaky fixtures and even inside the vacated galleries of carpenter ants and termites. Outdoors, the soil beneath rocks and other debris provide fertile conditions for nest establishment.
What do Odorous House ants eat?
Odorous House ants forage mainly for sugary substances, nectar, and the honeydew of aphids which they, like many species of ant, tend to farm and protect. They can often be found trailing each other along marked pheromone trails.
How Addison can help Odorous House Ant Infestations in the Future:
Inspect all incoming plant and organic matter before establishing it on your property or bringing it into your home. Even if the origin of an infestation is rooted out, it is important to be stringent in your implementation of physical controls; fill cracks in building facades, and seal window frames (refit if necessary). Keep outdoor spaces dry and open to sunlight, clear debris that creates humid and moist conditions for ant colony-building, and lift firewood off the ground. Establish a perimeter clear of organic matter of at least 1ft around the structure. Shrubs and tree branches should be cut back from your home to limit access points to the structure. Inside, kitchens should be kept clear of spills and crumbs; food should be kept tightly sealed, keep organic waste in the freezer, seal moisture drips and leaks from drains and plumbing, repair cracks and fissures in floors and walls. Most ants who invade homes tend to be ‘budding’ members of larger colonies that are working to establish smaller satellite nests. It is important to inspect moist and decaying wood and wood structures like decks, porches, sheds, playsets on your property and to remove any dilapidated structures or potential harbourages.