These ants are primarily nocturnal and feed actively from sunset to sunrise on other insects and plant foods. The main colony with the queen is usually found in trees, stumps, railroad ties, etc. and nests found in homes are satellites of this primary colony nest.
The carpenter ant can cause substantial structural damage when they infest a home. They don't eat the wood but hollow it out for nesting purposes leaving the wood prone to collapse.
Carpenter ants are quite common in Ontario and are normally about 4 to 7 millimeters in length. They are usually shiny, jet black in color with some variations of reddish brown or even greyish.
Carpenter Ants will seek out old or rotting wood. Contrary to popular belief the ants do not eat the wood. Instead, they like the damp wood as it provides an excellent venue for the ant to build their nests.