Wednesday, March 14, 2012

Energetic Ants

Soil temperatures are warming rapidly and this has stimulated the Allegheny Mound Ants, Formica exsectoides, to almost frantic activity.  Damage inflicted upon the mound over winter is being quickly repaired.  This particular blemish was created by a deer that chose to go over the mound instead of around.

Some late winter mounds support a covering of green growth composed primarily of non-native plant species.  Kentucky Bluegrass and a variety of mustards make up the bulk of the growth.  Some colonies tolerate the vegetation on the mound, while others will have the mound cleared of all greenery by mid summer.

Judging by the rate at which debris is accumulating, there must be some major excavation going on down below.  The grass plants are already becoming buried.

Some large loads are being brought to the surface.  This piece was too heavy for a single ant to lift and had to be drug out of the way.

At some holes the ants formed a ring at the entrance, all facing into the mound.  This didn’t seem to fit any logical defensive strategy.

It turned out that those ants were waiting to receive excavated material from ants inside.  The receiving ants carried the material away to be discarded.  They would then return to the hole and wait for more material to be passed up.

I didn’t notice any ants foraging away from the mound, but I did find a group working to drag a cranefly larva up the side of the mound.  If the temperatures remain warm, ants should soon be moving out into the field in search of food.


  1. I always enjoy getting the latest news on "your" ants, Steve.

    The other day, stimulated by an earlier post of yours, I brought home two flicker droppings from ant mounds to dissect under the scope. In addition to hollow and somewhat flattened parts of the resident Formica subsericea, there were also bits of 2 Myrmica species, and one each of Apahenogaster & Tapinoma. As this taxonomically disparate batch of ant bits shows, flickers like just about any kind of ant they can get on their their sticky tongues.

  2. Hi James. I never knew that Flickers fed that heavily on ants. I wonder if that's what they're after when they probe around in my yard. They seem to spend a long time at one place, which would be the case if they were feeding on an ant colony.