Winter Becomes Them

Ants are making a home in my kitchen and my bathroom. At first, I thought some dirt happened to fall in a somewhat structured mound near the toilet. I came home from work tonight, and actually saw the worker ants lugging long, thin pieces of debris from inside the wall onto a pile. They are sluggish from the Terro, but are still managing to build a nest. I've become obsessed with these ants. Where did they come from? How do they survive? Maybe it's time to get a pet--when I start posting pictures someone stop me, please.