In the past couple of years, from May to July, I've seen carpenter ants
in my house. It always starts in early May, and usually stops by June
or July. During this period (especially in May) I may see 1-3 ants per
day, about 3-4 days per week.
Are these most likely simply random foragers from outside nests that
found a way inside? (50x100' lot with large trees). If the ants had a
nest somewhere inside my house, would I more likely be seeing them
year-round (or at least from Spring until Fall) as opposed to just 2 or
3 months per year?
This is in Southern Ontario (Canada).