White-winged Crossbill fall under what birders in the Northeast refer to as "winter finches". These are a group of hardy birds that are normally found in winter along the northern edge of the United States and the boreal forests of Canada. They are Pine Grosbeak, Purple Finch, Red Crossbill, White-Winged Crossbill, Common Redpoll, Hoary Redpoll, Pine Siskin and Evening Grosbeak. During winters when their food source is scarce many of them make their way farther south in search of food. These are known as irruption years. It is a well studied phenomenon with annual predictions posted online. Here is this winter's. It seems unlikely that this crossbill will make its way to NYC this winter. Their scientific name, loxia leucoptera, means crosswise, slanting; white-wing. Despite decreasing numbers, the IUCN Redlist lists this species as "Least Concern" due to its extremely large range and large population.