05/14/2026
Carpenter ant swarmers all bunched up on a door. π Here's what's actually going on.
When you see a cluster like this, it's not random. These are reproductive carpenter ants (called alates) that have left the parent colony to mate and start new ones. They swarm in spring and early summer, usually after warm humid weather, and they're drawn to light and open spaces to take flight.
But here's the part most people miss. If they're swarming inside your home or right against the structure like this, the parent colony is almost certainly in or on the house.
A few things to know about carpenter ants:
π They don't eat wood like termites do, but they tunnel through it to build their nests, which weakens the wood over time
π They prefer damp or previously damaged wood, so leaks, rotted fascia, old window frames, and damp crawlspaces are prime real estate
π A mature colony can have multiple satellite nests connected to one parent colony, so finding one nest doesn't mean you found them all
π Seeing swarmers means the colony is mature, which means it's been there a while
Why are they bunched up on the door? They're either trying to get out to swarm or they just emerged from a nest very close by. Either way, it's a sign you need an inspection.
If you're seeing swarms like this on your doors, windows, or siding, give us a call. We'll track down the colony, treat it, and find the moisture issue that drew them in to begin with.