For years, the twice-a-year migration of billions of birds was one of nature’s most spectacular events that we never really got to see. That’s because most of the action takes place out of sight, far above us and often at night.
That began to change in the last decade with new technologies for tracking birds, and last week brought a milestone: The Cornell Lab of Ornithology completed a massive project that creates maps and animations for nearly all North American species.
The result is an unprecedented view of how birds move, arriving just in time for the spring migration.
This is big news for anyone interested in birds. The data in this project, all of which is free, will strengthen everything from scientific research and conservation to the power and precision of the tools you use on the birding trail.
The impacts are so far-reaching that Beverly and I couldn’t agree on what’s most important here. So we thought we’d each make our case and let you come to your own conclusions.
Canada Warbler / Photo by James Hully, Macaulay Library, Cornell Lab of Ornithology
Beverly: The best way to appreciate this work is to start by looking at one of these animations. They’re beautiful, with patches of bright colors flowing back and forth across a map of the hemisphere that represent migrating birds week by week throughout the year. I think these are the most compelling — and entertaining — of all the maps and illustrations that come under Cornell’s eBird umbrella. You can find a complete list of the maps by species here on the Cornell website.
For example, here’s an animation of how the tiny Canada Warbler travels the length of the hemisphere twice a year.
Not only can you watch the warblers’ weekly progress from far north Canada to Latin America and back, but you can use these maps to help figure out when they’re like to pass by you. And when you’re trying to find a bird you’ve never seen before, knowing exactly when the largest flocks are arriving is a huge help.
Anders: The point is that animations like the Canada Warbler, along with abundance, range and breeding maps, now exist for 610 species, which make up almost all of the species in North America, in archives Cornell calls status and trends maps.
The lab began putting these together about two years ago as a way to convert their raw bird data into compelling maps and show how birds move through the seasons of the year. The first batch of maps covered about 20 percent of the species, but the addition of the rest of the species opens all sorts of possibilities for comprehensive research and conservation approaches.
“This is a big jump in terms of the utility of the data project,’’ said Daniel Fink, a senior research associate at the Cornell Lab.
Most of the answers are guesses, since the bird wasn’t tagged and certainly isn’t talking. But Andrew Farnsworth, a research associate with the Cornell Lab of Ornithology who specializes in migration, said the likely drivers are genetic migration instincts that go off track, lack of food back home and changing weather patterns that are becoming more frequent around the globe.
In late summer, as the hummingbirds are preparing to migrate halfway across the hemisphere, they are in the midst of a feeding frenzy to bulk up for the journey. They consume their entire weight in nectar each day, which the Audubon Society calculated was the equivalent of a human drinking 18 gallons of milk.
