To accomplish this flight, the blackpoll warbler nearly doubles its body mass in staging areas and takes advantage of a shift in prevailing wind direction to direct it to its destination. When they fly southward over the Atlantic they burn, 0.08 g of fat every hour. This route averages over water, requiring a potentially nonstop flight of around 72 to 88 hours. They travel at a speed of about . Blackpolls can weigh more than when they leave the United States and lose 4 or more grams by the time they reach South America. Some of the blackpolls land in Bermuda before going on. Some birds, often with lower body weights, do not make it.