New Study Underlines Importance of the Boreal for Migratory Birds

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The Blackpoll Warbler has the longest migration of any warbler and, in fact, the longest migration of any Boreal songbird. Every year, Blackpoll Warblers make an incredible journey from North America’s Boreal Forest to South America. Some may choose to take short breaks in Bermuda or the Antilles along the way, while others appear to fly nonstop for three days (or more) to reach their seasonal southern homes. 

The fact that these small birds weighing less than half an ounce are flying amazing distances continuously for over 72 hours is enough to fascinate most bird enthusiasts, but there are other features to the Blackpoll’s migration that are just as interesting. For instance, they travel different migration routes when heading north than heading south—a behavior known as “elliptical” migration. They also have the longest period of migration of any warbler. You may think this is because of the long distance they travel, but it is actually due to the extended time they spend lingering on the mainland before making their overseas flight. In fact, people in the U.S. have reported seeing Blackpoll Warblers as late as October. 

Once they reach South America, they set up residence in the lowlands and foothills east of the Andes. Most stay in the northern part of the continent, though a few apparently continue on appearing as far south as Chile, which is the furthest south any Boreal breeding-warbler has ever been spotted.  
These small but mighty birds are considered common, but their numbers are in decline. At least part of this decline is likely due to their long migration. A new study released by Audubon found that birds making the longest migrations are at greatest risk. One can presume this is due to the increased probability of them coming into contact with hazards during their epically long journeys each year. 

The Blackpoll Warbler is not the only Boreal-breeding bird that travels extreme distances and faces increased risks. Birds like Lesser Yellowlegs also make epic journeys and similarly face greater exposure to potential risk factors. Considering the risks these migratory birds face, the need to ensure they have reproductive success is incredibly important. The Boreal is brimming with safe and abundant habitats perfect for migratory birds to successfully breed and raise their young. In fact, so many species breed here that it has been dubbed Norther America’s bird nursery. If this breeding habitat is compromised, whether due to climate change events like expanded forest fires or drought, or caused by deforestation or new industrial development, these migratory species may not introduce as many new chicks into the world thus limiting their ability to compensate for the losses faced during migration.  

Luckily, Indigenous Nations are currently responsible for the most ambitious plans to preserve the Boreal lands and waters that so many migratory birds rely on. Together, these Indigenous-led initiatives could protect more than 100 million acres of critically important Boreal Forest habitat. Audubon is working to elevate and provide support for these important initiatives such as Indigenous Protected and Conserved Areas and Indigenous Guardians programs across Canada.