The Night Shift: Birds On the Move
Every night, as the weather cools and fall closes in, more than a billion birds take to the skies.
By morning these exhausted travelers are in our native gardens--essential pit-stops for these migrants, many traveling several hundred miles per night and at speeds of up to 55 miles per hour.
As the American Bird Conservancy puts it: “To keep up with them, you’d need to run the entire width of the state of Montana in a day.”
Or in a night, if you’re chasing the migration.
Why fly in the dark? According to Dr. Kevin McGowan, of the Cornell Lab of Ornithology, when we shut out the lights, the birds rise, flying by the stars and an ability to "sense" the Earth's magnetic field, using it to detect north and south. They're also safer from predators at night.
By dawn, they drop back down, ready to rest and eat.
Why do they go?
Temperature is not a major driver. According to Cornell’s All About Birds, birds can withstand freezing temperatures as long as food is available. As days shorten and insects disappear in the north, there's not enough food to keep them here.
Birds You're Most Likely to See in New England
Dozens of species of Warblers, along with Flycatchers, Vireos and Ruby-throated Hummingbirds – the migrants, not the ones who've been slurping on your Trumpet Vine all summer. Gray Catbirds are heading to Central America while Orioles are on their way to the Caribbean.
When to Look
Like mornings? Grab your coffee and head to the garden — the best time of day to see – and hear – the migrants.
Not really a morning person? Watch for cold fronts and set your alarm. The northwest winds that typically follow cold fronts push the birds south, where dozens or more land in your garden along the way. You wouldn't want to sleep through this!
Once on the ground they hunt for insects, berries, and seeds — all of which a well-planted native garden provides in abundance.
Native fruiting shrubs like Elderberry, Arrowwood Viburnum, Bayberry and Winterberry are critical fuel stops. Native seed heads — goldenrods, asters, coneflowers — feed sparrows and finches. And the insects that live in and around native plants feed the warblers and flycatchers, which prefer bugs to berries.
Don’t have a yard? Here are some great spots in Massachusetts to view migrating birds.
How Do We Know How Many Birds Are Flying Overhead?
In the early days of radar used to detect weather patterns, mysterious signals--referred to as angels--puzzled operators.
It wasn’t until the 1940s, based on the studies of pioneering ornithologists including David Lack and George Varley, that scientists figured out that birds were creating those signals.
Using a system called BirdCast, scientists can distinguish birds from raindrops because of their unique flight patterns and speeds. BirdCast, a collaboration among universities including the Cornell Lab of Ornithology, compiles about 100 gigabytes of data every night, refreshing every 10 minutes.
One night I learned from BirdCast that an estimated 71,300 birds crossed my county in Massachusetts alone — peaking at 19,000 birds in flight simultaneously at 8:40 PM, flying south at 21 mph at 1,800 feet above the ground.
You can check your own county's numbers at BirdCast’s Migration Dashboard.
Fun fact: The longest long-distance flyer is the Arctic Tern, traveling more than 49,000 miles each year, covering more distance than any other migratory bird.
Their journey, from Arctic breeding sites and summers in the Antarctic, is roughly equivalent to flying around the world twice.
The bird making the longest nonstop flight, however, is the Bar-tailed Godwit, traveling 7,000 miles nonstop.
Keep your cats indoors
Cats are not natural predators; European settlers introduced cats into the United States approximately 400 years ago. Cats have since become the No. 1 direct threat to birds, killing approximately 2.4 billion each year.
For more on keeping cats indoors, visit the American Bird Conservancy’s web site here.
About the author
Jennifer Anderson owns Tree Talk Natives, a native tree and plant nursery along Massachusetts' South Shore. A former news reporter, she loves to write and talk about native plants. Jennifer also gives garden consultations and presentations on native plants. She can be reached at jennifer@treetalknatives.com.
Sources:
The Basics of Bird Migration: How, Why, When, and Where, All About Birds, Cornell University. May 13, 2026.
Five Fantastic Bird Migration Facts. American Bird Conservancy
Great Bird Migration Spots. Mass Audubon
Imbler, S. How a Tern Broke the Record for the Longest Known Migration. Audubon. June 28, 2016
Keeping Cats Indoors. American Bird Conservancy
Radar Ornithology. BirdCast. Cornell University
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