If you have been outside lately, you don’t need me to tell you it is still blisteringly hot in South Central Florida. When you sweat buckets just running errands or leaving your office to grab a quick bite for lunch, it can be hard to believe fall is upon us. The heat index may not agree but cooler weather is coming, and birds are on the move.
As predictable as the flipping of a calendar, migratory birds follow seasonal routes to breeding and wintering grounds. The inspiration for our term “snowbird,” many avian species prefer to avoid the snowy, blustery weather, heading for the warm tropics of Florida and beyond.
It is incredible to consider the extensive flight distances of many species, particularly the tiny warblers. Measuring a mere five inches, most warblers weigh the equivalent two quarters in your palm. Even so, these colorful bits of fluff fly hundreds to tens of thousands of miles every year. Migration is linked to specific breeding or feeding behaviors. For example, if insects are a main staple of diet, birds must migrate from cold weather regions to survive. The shortening of days and hours of sunlight prompts birds to begin movement.
Those which have the farthest to go leave the earliest as though they are aware of the distance stretching out before them. The black-and-white warbler, which favors Florida for the far northern reach of their wintering range, moves as far south as South America, the West Indies, and Central America from its breeding grounds in the upper eastern United States.
Whether the birds fly along the coast of Mexico, wing over the Gulf of Mexico to the Yucatan Peninsula or take to open water from Florida to the West Indies, these little birdies face all manner of hazards. From vast expanses of ocean to overcast skies and bad weather, communication towers, air turbines and glass-sided high rises along coastal regions, migration is a perilous time. Fat stores provide the necessary calories and night flights allow for daylight arrival to alternately rest and feed for the next leg of the journey.
From banding to radio tracking and radar mapping, bird migration has been studied for years. Recent radar mapping now predicts regions of “fallout” or areas where these exhausted birds will likely land after ocean crossings or long miles of flight. Avid birders use this information to pick where and when they will likely see migratory warblers in large numbers following a big flyover.
From thousands to tens of thousands of miles every year, warblers traverse the skies popping by to brighten the day of those willing to watch for their travels.