Spring is here. This year, the winter that wasn't, has felt like spring every two weeks since Thanksgiving! As far as the birds are concerned, Spring is not an event of weather, but of seasonal change.
Some migratory birds (Robins, for example) have been overwintering on Long Island for a few years now, probably because of warmer weather. However, most birds that migrate do so because a set of signals has told them it is time to go, not because it's warmer. Keep in mind, many of these birds come all the way from South America, where the climate is so different it has no relation to Long Island weather. The major signal that drives birds is the number of hours of daylight they experience. When daylight hours start to increase in the early Spring, it causes actual changes of the hormones inside the bird that drive the instinct to move.
One important point I like to mention every Spring is that it is not necessary to quit feeding at this or ANY time of year! There are many myths about birdfeeding and when to stop, all of them wrong! Most seed eating birds (Cardinals, Chickadees, most Sparrows, Bluejays, Tufted Titmice, etc etc etc) do not migrate, they are here year round, and of course, they EAT year round. Birds still need to eat in July, so why not feed them?