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The male Blackpoll Warbler is a striking bird, clad in a combo of black, gray and white, ending in some bright yellowish-orange feet. The male’s body is marked with a black cap, gray back with black stripes, and with flight feathers tinged with a diluted yellow along its edges. Below, it’s white belly is streaked with black. Females have a similar plumage as the male, but just more muted, overall much more grayish with fine black streaking. It is also unfortunanly one of the fastest declining songbirds, it is estimated that they have lost nearly 88% of its population in the last 40 years.
This warbler is also famous for its migration patterns and is considered one of the finest examples of bird migration.
This 12 gram songbird breeds across the boreal forests of North America and spends its winter months down into Puerto Rico, the Lesser Antilles, and northern parts of South America. Those two areas are quite the distance from each other, leading to an incredible migration that these warblers have to complete twice a year, especially those who breed on the western parts of their breeding range.
Once the breeding season for this warbler is done, they prepare to make their incredible journey south to their wintering range. But before they leave, they have to prepare for the calories expenditure that this journey will require. In preparation, they will gorge themselves on insects and bulk up their fat reserves. Often, this will result in the Blackpoll Warbler almost doubling its weight in the process. Going from the average of 12 grams up to 20 to 24 grams.
The first leg of their journey has them arching across all of North America down to the coastline of eastern North America, typically anywhere from New Jersey to Florida. The second part of their journey is the one that leads to it being an extraordinary example of bird migration. From the coast, they will then travel the rest of the way to their wintering grounds over the open ocean, making it one of the longest overwater flights seen in any other songbird.
This trip back to their wintering grounds, will have them fly nonstop for up to three days over open ocean, a trip that is from 1,400 to 2,113 miles! Throughout this southward trip, they can also get help from a natural phenomenon, strong tailwinds that give them a boost on their journey south.
This entire trip can end up being 12,400 miles round trip, a trip which they will embrace on every year. This all while trying to avoid threats from predators, window and car collisions and storms.
This incredible migration pattern was only discovered recently due to geolocation tracking technology improving so much that they can now make a unit to be created small enough to be attached to many small birds. These current geolocations weigh only .5 g, which is about half the weight of your average paper clip and comes with a battery life of up to 12 months.
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