[EBB Sightings] Western Tanager

Greetings Birders:

When I awoke this morning to yet another hot day, I heard a Western Tanager calling its characteristic double "Pit-it."? I have read other reports of tanagers on the move. Seldom are the numbers as high as in May when they are traveling north through the coastal lowlands on their way to their breeding grounds in the Sierra.

But why so soon when days are still warm in the Sierra and nights rarely below the mid-thirties?? Insects and other foods such as ripe berries must still be plentiful for at least another six weeks.? What is changing is day length.? Experiments with caged birds and artificial light show that no other factor so profoundly affects bird behavior.? Lengthening hours of illumination (artificial or natural) and birds undergo the physical changes that prepare them for breeding. Shorten the hours of light, and birds even in cages, are seized with a compelling restlessness to begin their southward migration.? It appears that daylight preempts even food supply. 

So here is one of our migrating tanagers on perhaps the hottest day of late summer, spending a day or two "fueling up" and resting before pushing on south to regions unknown to most of us.
 
Phila Rogers?