Spotting big black ants inside your home is bad enough, but the creep factor increases when they sport wings. Flying ants likely are carpenter ants, whose breeding females use wings to travel to new nesting sites. The carpenter ants might have come inside by chance, or they could be nesting in your walls.
Identifying Carpenter Ants
Carpenter ants vary in size, even among the same colony, but they tend to be beefier than many other ant species. They can be all black or show touches of red. Because they inhabit some of the same areas as termites, the two insects often are confused. Termites are light-colored and have straight bodies, while carpenter ants have two separate body sections separated by a narrow waist. Their upper body sections, their thoraxes, are evenly curved, then they have single small notes between their thoraxes and the lower body section -- some ants have two nodes, making this a key factor in identification.
Females With Wings
Female carpenter ants capable of breeding tend to be larger than the workers. Their back wings fall a bit shorter than the front set, unlike the wings of termites, which are equally long. Many females born in a colony, which is why you could see them foraging in your home. When they're fully mature and ready to mate, they fly off to start their own colonies -- this is the only time they use their wings. As queens, they typically lose their wings.
Whey They Come Inside
Carpenter ants don't eat wood, but they take advantage of the shelter provided by damp wood to make their nests. Typically, this means rotting tree stumps or roots, but your house becomes attractive when you have wood affected by leaks or weather damage. They burrow into the wood and carry the excess wood outside the nest, often leaving a pile of shavings that helps you identify the location. When they're foraging inside your house, they're likely seeking protein from meat or sugar from items such as jelly or syrup. Seeing the winged ants inside is a sign you likely have a colony in your home somewhere.
Many carpenter ant nests remain hidden inside walls, so you might need help from a professional exterminator to rid your home of the pests. Spraying an insecticidal dust inside your walls through the electrical outlets can help control the population, but it rarely kills the nest. Ant bait traps work differently, however -- foraging ants take the bait back to the nest as food and share it with the others, which can eventually kill the nest. Watching in the evening for their return helps you determine where the nocturnal ants like to forage, so you can try to set out ant bait traps to take care of the problem on your own.