PORTAGE, ALASKA — Wildlife biologists in Southcentral Alaska have launched a landmark scientific initiative to track a Rufous hummingbird’s entire migration journey from its northernmost breeding grounds in Alaska all the way to its wintering territory in Mexico.
The ambitious project—led by biologist Todd Eskelin of the Kenai National Wildlife Refuge—aims to solve long-standing mysteries surrounding the tiny bird’s roughly 4,000-mile epic trek. Relative to body size, the Rufous hummingbird (Selasphorus rufous) undertakes one of the longest migrations of any bird on Earth, flying nearly 78 million body lengths across North America.
The study reached a major milestone during a field operation in Portage, Alaska, where 13-year-old Bella Eskelin gently held a captured Rufous hummingbird while research teams fitted the minute avian traveler with lightweight tracking technology. Weighing barely 3.5 grams—less than a nickel—these feathery pollinators present a significant logistical challenge for field researchers. Standard solar-powered satellite transmitters and geolocators must be miniaturized to a fraction of a gram to ensure they do not impede the bird’s aerial agility or extreme energetic demands.
Previous banding programs confirmed that Rufous hummingbirds migrate along a vast clockwise loop across North America, following the blooming flowers along the Pacific Coast northbound each spring before navigating south through the Rocky Mountains in late summer. However, fine-scale data detailing exact migratory stopovers, daily flight speeds, and precise winter destinations in Mexico has remained elusive until now.
In addition to mapping migration corridors, scientists hope the tracking initiative will shed light on how climate change affects delicate pollinator routes. Shifting bloom times and ecosystem shifts threaten to mismatch flower availability with the arrival of migrating birds. Researchers anticipate that tracking individual hummingbirds in real time will offer critical insights into conservation strategies across international borders.
With information from Anchorage Daily News
