Blackpoll warbler-Amazing non-stop flights across continents


A picture of a blackpoll warbler.

The little blackpoll warbler weighs only 20 grams, less than three fourths of an ounce, and is but five inches (13 cm) long.

Nevertheless, its migratory feats are colossal.


Blackpoll warbler migration



When fall approaches, it leaves its summer home in Alaska and flies southeast across the North American continent to the Atlantic coast, eating voraciously along the way, because the warbler’s journey has just begun.

Along the coast of New England, the blackpoll warbler waits and watches the weather.

It somehow knows exactly what weather it wants—a strong cold front that will pass southeast over the coast and out into the Atlantic.

When the cold front arrives, the little warbler sets off, helped by the favorable winds as it flies southeast—out to sea.

The cold front also means that there will probably not be any tropical storms to contend with en route—a wise choice of weather!

Flying southeast puts the tiny bird on course for Africa, hopelessly distant and not its destination. But the blackpoll warbler doesn’t change direction.

It flies nonstop past Bermuda, climbing to altitudes of 21,000 feet as it nears Antigua.

It is cold and the oxygen is scarce at that altitude.

Why is the little warbler up there?

Because there it finds the prevailing winds that blow it west to its real destination, South America.

After a nonstop flight of over 2,400 miles in more than three days and nights the warbler arrives on another continent, right on target!

Scientists marvel at the feat performed every year by this little bird. How does it know exactly what weather conditions to look for?

How does it know just when to change altitude to find the winds that will take it to South America?

How does it know to select exactly the proper navigational heading that will allow it to intersect with those winds at the right spot over the ocean?

Scientists cannot fully explain it.

There is, however, a good reason for the blackpoll’s unusual route.

Its sea route to South America is much shorter than an “island hopping” trip would be, and there are few predators to worry about.

The blackpoll warbler can make the nonstop flight, equivalent to a race horse running consecutive two-minute miles for 80 hours, because of its specially designed metabolism.

“If a blackpoll warbler were burning gasoline instead of its reserves of body fat,” notes one scientist, “it could boast of getting 720,000 miles to the gallon!”