The bees were bringing in pollen on February 19th. You can see pollen baskets full on two bees in this photo. That is usually a sign they are raising brood. It may just be because the weather is really warm and the maple trees just started producing pollen, so the bees are loading up early while they have the opportunity. The forecast says we will be cooling off in a few more days. So hopefully they did not start too much new brood.