Good weather - Bad birding

New England has received a long streak of steady, high pressure with north-east winds, seasonably warm temperatures and almost no precipitation. In short blue skies and cool breezes prefect weather for some spring bird watching… or is it? For these few weeks in May New England sees passage of millions of songbird migrants making their way north to the boreal forests and taiga of Canada where they will be breed during the summer months. This short passage is a like watching the marathon for 6 hours just to see the leader pack run by in the blink of an eye. 

These tiny birds may fly as many up to 1500 miles in just a few weeks from places as far as central Argentina. Threats along the way include the lure of windows and light up skyscrapers, natural predators like hawks as well as domestic predators like house cats. Weather also plays a huge factor in the life or death of these birds. A spring storm or cold snap, excessive heat or a head wind can be the difference in success and failure. It will come as no surprise that a head wind is the most prevalent weather obstacle. For anyone who has ever tried to run, bike, even walk into the wind you will know it is harder and more energy is used than when moving with the wind. During the spring birds will use a southerly tail wind (wind blowing from south to the north) to aid in this long journey. When the wind is coming from the north “northerly wind” birds will often reroute or wait for a change in wind direction.

In New England a north or northwesterly wind occurs when a high pressure system pushes a low pressure system out to sea. High pressure systems are not only the large “H’s” on the weather map they are also associated with cool, dry weather on the ground, and cloudless, clear blue skies and sunshine above – the archetypal “nice day.” April showers bring May flowers and spring as a whole is often a drizzly month. Days of off and on spitting light rain coat the flowers and tree buds. This type of warm, humid air is typical of a low pressure accompanied by a south wind – good migration conditions. What we've seen this spring (April into early May 2013) is a stationary high pressure sitting just west of New England. This steady high pressure has meant clear skies, no rain, and a near consistent northeast wind – terrible conditions for migrants. So let's pray for some humid air, light drizzle and a breeze from the south and on it will come the birds!