I recently heard about a warbler overwintering at a private greenhouse in Deerfield and followed up with one of the workers at the location to get some details. He described the bird as a Common Yellowthroat. I secured permission to stop by at some point and document the occurrence of the bird. I decided to take a ride up to the location after getting out of work this morning. Once I arrived I caught up with Trystan and he led me right away to the greenhouse. The greenhouse is used to grow a variety of plants and they cannot use insecticides so the presence of an insectivore bird has been very welcome addition to the staff and Trystan stated the numbers of insects causing issues for the plants is way down this winter thanks to the bird. Apparently the bird first appeared in the greenhouse late in the fall and has stayed put ever since. It took several minutes of looking but eventually the bird popped in to view on occasion as it fed quite actively and hardly ever stayed still for long. I managed to get a few photos of the bird as it worked its way through the jungle like tangle of plants. The bird is free to leave via a louvered area that is opened occasionally but seems quite content to ride out the winter in the warmth of the greenhouse with a ready supply of insects, water, cover and a lack of predators (not to mention the warmth of the greenhouse during the cold New England winter). The species typically winters in the southern part of the United States but can occasionally linger a bit into early winter (I have had a single record of the species in mid January in Amherst in 2019) but otherwise have never had the species in the heart of the winter around here.
