Monday, September 7, 2009

The Labor Day Ant

Lasius neoniger is a very common North American ant. It's called The Labor Day ant because their mating season starts from mid August and continues into late September. Though not found everywhere, the places where they do occur they tend to be very abundant almost to the point of being invasive. They tend to nest in open fields or along forest edges. Nuptial flights are held in the late afternoon just before the sun goes down. All this can spell disaster for out door barbecues and gatherings nation wide.

Colonies release thousands of winged males and new queens into the air all at once. For many parts of the country Labor Day falls on the peak of their mating season. Thankfully the main swarm usually takes place high up in the air but having the swarm over head doesn't necessarily spare anyone. Once the flight begins alates will be taking off and landing for hours. Taking off usually stops at sundown but that still leaves hundreds of them in the air. They're drawn to lights once night falls. And this all starts up again on the next day, weather permitting of course.

The other thing Lasius neoniger is know for is ruining the sport of golf. See Here Because they like to nest in open fields golf courses are perfect nesting spots. These ants like to make small mounts too and they make putting areas look messy.

Lasius neoniger isn't entirely to blame though as dozens of other Lasius species are also flying. Other genera are doing this too but most get their flights out of the way in the early morning. Lasius alienus (pictured above) is the forest dwelling counterpart to L. neoniger. Note the legs are more yellow, and the abdomen lacks the velvety sheen of hairs. Neither of these traits are consistent because they can hybridize. L. alienus just tends to nest in dead wood or a combination of wood and dirt.

Not the best picture in the world, but L. neoniger is on the left, L. alienus is on the right. The other issue to look for is behavior. L. neoniger make for much better parents and attentively guard brood even when disturbed. L. alienus queens I've found when disturbed will run around frantically. Another interesting point is the queens pictured above were nesting in the same test tube tending the same batch of workers. Lasius queens seem to tolerate one another even when they are not the same species.

Lasius flavus is the other common one flying now. Queens are much smaller then the other two and tend to be a hard to describe brown-orange color that in the right lighting I swear looks green. Unlike the other two they have orange workers instead of black. But they shouldn't be confused with parasitic species that have just started flying in Canada. I'll save them for another post.