Monday, November 22, 2010

Ant Hill Toppers

After finding scat being used to cover the hill of an Allegheny Mound Ant colony, I decided to look around to see what other colonies were using to cover their hills. I did find one other mound using scat, but the most abundant material being used as a protective cover was cedar twigs.

I guess this makes sense since the twigs are so readily available here, are easily handled by the ants and are fairly durable. This ant was one of many bringing cedar twigs to form a cover over a recently damaged portion of the mound.

Several mounds were covered with bits of Reindeer Moss, a type of branched lichen that grows abundantly in the barrens. Each lichen bit is capable of developing into a new lichen colony. I’ve seen Reindeer Moss growing on abandoned mounds and this may be the way it came to be there.

This hill had several bits of moss on its surface. I wonder if the individual ants that go out to collect this material concentrate on one particular type of material. There may have been a single individual ant that for some reason brought back only moss tops.

The numbers of tiny stones vary between mounds. My first thought was that the stones were excavated during the construction of underground tunnels and chambers. That didn’t explain why they were on top of and mixed with the other hill topper material. If they were part of the excavation spoil, I would also expect to find excavated soil arranged in the same way. It seems more likely that the stones were collected from the surrounding area and added to the layer of protective material.

One hill had a large collection of Nostoc algae. Since Nostoc turns gelatinous when wet and tends to slide down hill, this material doesn’t seem to be a good choice for mound protection. Much of ant behavior is a response to some chemical signal and I suppose there are times when those signals can be corrupted with a corresponding improper action on the part of the ant. It could also be that the ants were suffering because of the drought and found hydrated Nostoc to be a way of bringing water to the colony.

Tiny snail shells were common on many mounds. I don’t know what species this shell represents. They were so small that it almost took magnification to identify them as shells. Ant mounds always have something interesting to offer. I enjoy this time of year when the ants tend to stay confined to the mound and they don’t swarm up your legs the minute you walk up.


  1. I learned something new again today from reading your blog!! Now I can't wait for the opportunity to go out and test my new found knowledge!! ~karen

  2. Thanks, Lois.

    Hi, Karen. I doubt that you need much encouragement to get outdoors, but I'm glad I gave you something new to look for.