Migration has begun!
733, a subadult female eagle that we began tracking in 2022, appears to have started her migration south! At the beginning of October, she was north of Rankin Inlet in Nunavut, roughly 1,350 miles north of her capture location. As of today’s post, she had moved about 451 miles south, skirting the edge of Hudson’s Bay, to a location near Churchill, Manitoba. She’s not far from 833’s last known location near Port Nelson right now: an area just north of the northernmost place we tracked a Decorah Bald Eagle. Use the map below to explore our eagles’ October locations in any given year, or take a look at 834 and 733’s maps. A thousand thanks to Brett Mandernack and Ryan Schmitz for sharing their data and maps with us!
Why do Bald Eagles stay farther south than Golden Eagles?
We’ve written about the adaptability of Golden Eagles. While Bald Eagles are fairly flexible, they prefer fish over other prey, have a more restricted prey base than Golden Eagles, and have a deep-rooted preference for forested terrain: something we’ve referred to as a stick-shaped hole in their heads. Golden Eagles 733 and 834 are summering in an area above the tree line but most Bald Eagles – D1 was an exception – probably prefer to stay within the Northern Forest biome: an area filled with tall trees, lakes, rivers, and fish.
People don’t appear to live in most of the places that 733 traveled over. The interior of Nunavut and the Hudson Bay lowlands are as much water as land in some places: a landscape of ancient igneous rock scoured by glaciers as recently as 11,700 years ago. Since there aren’t many roads, travel is done primarily by water or air and most cities are coastal. It’s a marvelous place for birds, with at least 295 species nesting or summering there.
Changing landscapes
I sometimes think about the different landscapes that roll beneath 733’s wings as she travels south. She’ll move from the Arctic through the Northern Forest through the Prairie to the Driftless. Roads will appear and towns will grow larger. Churchill, the town she’s nearest now, is a bustling city of 900 people and even more polar bears: a lot smaller than Decorah Iowa, but a lot busier than her summer location!
Forest will begin giving way to tiny scraps of cropland in southwest Ontario, growing ever larger as 733 moves toward her wintering grounds. The flat terrain of the northern prairie will begin to fold and wrinkle as she approaches the Driftless, and people will be everywhere. By the time she lands on her wintering grounds, the human presence will be a constant hum and her landscape will be a patchwork of fields, steep forested coulees, cities, and roads: far different from the place she summers in.
We’ll keep everyone posted as 733 and 834 come south. Their movements tell us that this is an excellent time to watch the Flyway for late season migrants like Bald Eagles, godwits, plovers, and Tundra Swans. Watch here: https://www.raptorresource.org/birdcams/flyway-cam/. To follow the travels of any of the eagles we’ve tracked, go to https://www.raptorresource.org/learning-tools/eagle-map/.
The Raptor Resource Project