Mesmerizing Migration: Watch 118 Bird Species Migrate Across a Map of the Western Hemisphere

By Pat Leonard
January 20, 2016
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For the first time, scientists at the Cornell Lab of Ornithology have documented migratory movements of bird populations spanning the entire year for 118 species throughout the Western Hemisphere. The study finds broad similarity in the routes used by specific groups of species—vividly demonstrated by animated maps showing patterns of movement across the annual cycle. The results of these analyses were published today in the Proceedings of the Royal Society B.

animated map of bird species migrating in western hemisphereEach dot represents a single bird species; the location represents the average of the population for each day of the year (see paper for a more precise explanation of the “average location”). Here’s a key to which species is which.

“We used millions of observations from the eBird citizen-science database,” says lead author Frank La Sorte, a research associate at the Cornell Lab. “After tracing the migration routes of all these species and comparing them, we concluded that a combination of geographic features and broad-scale atmospheric conditions influence the choice of routes used during spring and fall migration.”

La Sorte says a key finding of the study is that bird species that head out over the Atlantic Ocean during fall migration to spend winter in the Caribbean and South America follow a clockwise loop and take a path farther inland on their return journey in the spring. Species that follow this broad pattern include Bobolinks, Yellow and Black-billed cuckoos, Connecticut and Cape May warblers, Bicknell’s Thrush, and shorebirds, such as the American Golden Plover.

“These looped pathways help the birds take advantage of conditions in the atmosphere,” explains La Sorte. “Weaker headwinds and a push from the northeast trade winds as they move farther south make the fall journey a bit easier. The birds take this shorter, more direct route despite the dangers of flying over open-ocean.”

The study finds the spring migration path follows a more roundabout route but the birds move faster thanks to the presence of strong tailwinds as they head north to their breeding grounds.

For species that do not fly over the open ocean, the study finds that many use the same migration routes in the spring and fall. Geographic features shaping this pattern include mountain chains or isthmuses that funnel migrants along narrow routes.

“It’s an exciting new area of research,” says La Sorte. “By using eBird data and other forms of migration tracking information, we’re getting a more detailed picture than ever before about where and when birds migrate. That’s the kind of information we need to make smart conservation decisions for species that live in vastly different regions during the year. Citizen science makes it possible to do this for populations across an entire hemisphere.”


La Sorte, F.A., D. Fink, W.M. Hochachka, and S. Kelling. 2016. Convergence of broad-scale migration strategies in terrestrial birds. Proceedings of the Royal Society B, 10.1098/rspb.2015.2588.


  • Phyllis H. Buckman


  • Janet York Marquez

    Thank you for your research. My maternal great Aunt Bee & Uncle Gene were birders (bird watchers and hiking club) in Louisville, Kentucky ~ happy whistler

  • Rey Sta Ana

    Just wonderful. Any chance we can see this this done with the East Asian-Australasian Flyway.? Thanks a lot.

  • Manuel Zafnath Cornejo

    The Bird Watchers are key for gather this information, Good Job Twitchers’…!

  • Julia Rowe

    Love this, can you link the bird types to the dots…like when we move our mouse over the dot we can see the species?

  • Fascinating!

  • Kris


  • Theresa Campbell

    So why were red breasted Robins still hanging around my balcony in January 2016 in #Chicago, Documented by Tom Skilling. A whole flock of them were near Wrigley Field in January 2016.

  • Bella Bunny Boswell

    I live in Hawaii. Wish you had included birds that migrate from/to here.

  • PostmanSays

    I think if you go onto Ebird you can see how widespread this is.

    Contrary to popular opinion, Robins are not that unusual across the north in the winter, and they do flock in winter.

    But this year, south of Lake Ontario, the flocks have been huge, and ever-present.

    Lots of theories why. Most center around the weather and availability of food this year.


    Goodnight, wonderful this information where data was compiled and was shaped.
    I would like to know who did this work program and if you have any information affectation airport for raptor migration.

  • Rand0Mone

    Cool animation!
    Does anybody else have difficulty with it not auto-scaling to your device? I have viewed this with 4 different browsers on 2 different computers, on a tablet and on a phone…. can not view the entire map on any of my devices.
    If there is a setting someplace that I am missing, please enlighten me!

  • Debra Gilmore

    Use the CTRL key with the – key to reduce the size on your screen. On laptop or desktop computer.

  • hmg

    I find it odd that non of the dots move over the Chesapeake Bay area, yet it is an area where many migrant birds feed and rest on their routes north or south. Anyone care to explain why?

  • Yojimbot

    so freaking awesome!

  • Very impressive.

    Species by species views would be good too.

  • Wow! I can’t wait to share this with my students. Love it!

  • Bill Everitt

    Bravo! These two videos are a marvelous presentation of what must be a staggering amount of data. Very cool. Congratulations!

  • Rick Sacks

    There’s one bird that moves from the Falklands to the middle of Chile. Which one is that?!

  • jean guy

    Wow, birds are amazing! My favorite!

  • timothy_g

    Using Chrome do CTL+ MouseWheel to increase or decrease the size of the display area

  • Bob Fritz

    It says there are no spring-migrating birds in NE Ohio. That’s ridiculous and not true.

  • Zircon Zircon

    Many of these species migrate to and from Newfoundland in eastern Canada, but only one of the dots comes anywhere near the island. (And, that is a species I have never ever seen.) Is this because there has not been enough recorded information?

  • drkwarta

    They are die hard Cub fans and will not leave until they win the Pennant!!!

  • Todd Dolce

    Impressive,….Would love it if the dots were actually the actual bird species icons…but I know that would take a bunch of time.

  • Kathy Barker

    What a beautiful representation of the magnificence of migration! Show this to little kids so they can understand the connectivity of the world. Sometimes I just love this planet.

  • Todd Dolce

    Apparently they just pass through Ohio onto other final resting points….so yes,..they do go to Ohio,..but also move on to other locations….The ones that stay there may be Browns fans. Actually in seriousness,…I think the stopping points are the furthest each bird will migrate….not necessarily their single location.

    I could be wrong though.

  • Jan Ray

    Very cool. I agree with those who have suggested somehow linking the dots with the particular species. Nonetheless, this is a great illustration of migratory patterns.

  • Bob Fritz

    Maybe but it appears that none even move through here.

  • Vicky Fountain

    Love it! I also agree, it would be fascinating to see the different species, but I know that might not be do-able :)

  • Vicky Fountain

    It may be that they didn’t include the particular species of bird that you see in your local area.

  • Rand0Mone

    Thank you Timothy and Debra, I appreciate your feedback!

  • Howard Hofelich

    what a great video presentation!

  • circusvue

    For the birds who take the loop out over the Atlantic Ocean, could they be following some ancient route over what was a land mass at one time?

  • Carol Davick McDowell

    I, too, tried to place my cursor over the dots hoping to see which species were represented by each dot. That would be awesome if you have that capability. This was very cool, and kudos to all those that made this visualization possible!

  • Bob Fritz

    Every spring we do the census (about 40 of us) and we get about 135 species in one day. At least 80 either migrate here or are migrating through.

  • Linda Green

    Where are my favorites, Sand Hill Cranes?

  • MJ

    For some unknown reason, I cried the whole time while I watched the migrating birds. I miss them so much when they’re gone, but worry about them when they stay and we have a cold winter. It breaks my heart. I can never wait until spring; to hear the beautiful voices when I awake early before anyone else. The birds sustain me.

  • DigMed

    Scroll down a bit in the email and there’s a link to a number system that identifies each bird. As you can imagine there’s a lot of areas where the density of the birds in one place makes it hard to see the number but you can pick out and follow all the birds if you have plenty of time and patience.

  • DigMed

    I’m amazed at the density of NA birds wintering in Mexico and Central America. I’m going to see if there’s a birdwatching tour of all those countries.

  • Nancy


  • Devika Rani

    Can you link the bird types on the migration routes. Its great to watch its path. Recently was watching the Tri-coloured munia at one location. The accuracy at which the flock moves is like a dance. 200-300 birds on precision flight and landing.

  • Devika Rani

    Birder from India watching the North and South American migration of birds . So please include the species name. We have a similar migration between North and South of India . We have winter visitors from your country and Europe too.

  • Willy Worley

    Really enjoy seeing the animated migration routes, Helps me to decide if the infrequent sightings of Robins here in Palm Coast Florida are coming or returning north, Have to check this map out further, Just as soon as I return from my bird sighting walk At Princess place Preserve’

  • DigMed

    I’m amazed at how tough birds are considering how small and delicate they are compared to so many other vertebrate species. They survived the major mass extinction event of 65 mya. I have a feeling they’ll be here long after humans go extinct (by their own devices).

  • DigMed

    I’ve been trying to put up a link to the video that has a number key and list to identify all of the birds on the map but somehow this is not being allowed. It’s in the original email.

  • tyler

    Of course it’s ridiculous and not true, but I don’t think it says there is no spring migration in OH. Birds don’t migrate as a single mass, so that can’t be what the dot represents. The paper seems to be behind a paywall, but my guess is each dot represents a calculated “center of mass” for all reports of that sp. at each time increment. I see some spp. at times flicker in & out of existence, or jump around less smoothly — I’d suppose that represents no or few reports. IOW, NE Ohio just never happens to be the average location for all North American reports of any species. Way cool data display!

  • tyler

    Look at the related stories sidebar for “Animated Occurrence Maps Show Birds’ Migration Across Entire U.S.” Google that phrase will also get you there. Just across 48 states, not the entire hemisphere — but another exciting representation of mass data. There are even migrating birds shown in NE Ohio.

  • RL

    Wow! Very impressive! Which software did you use for the animation?

  • noboundryman

    We would all be better off if Mr. Trump and his well healed fellow oligarchs would donate a few billion to bird research, and conservation, because they’ve cleaned me out. It’s hard to describe my love for birds. There is no greater source of joy, and peace for me, than to join with their spirit in the beauty danger, and freedom of migration to exotic locals, the way our own ancestors did thousands of years ago. Even though I understand the evolutionary causes for their variety, coloration, and habits, it’s still impossible for me not to view them a sacred in some metaphorical way. Love is the only way to characterize it.

  • InvitedGuest

    Very cool viz! Just saw some cranes flyover while playing golf yesterday

  • Geoffrey Bryce Frasz

    what this video shows is how little we know about birds and migration in Brazil!

  • CraigOlsen

    I see nothing.

  • lejardin22

    Perhaps I am misunderstanding the map. I live on the North Shore of Massachusetts right next to Cape Ann. Plum Island Federal Reservation is a bit to my northeast and I understood that a flyway goes over it. However, this map indicates only two species crossing my area, one of which I have never seen, the Bicknell Thrush. How can this be?

    Susan Gruber

Mesmerizing Migration: Watch 118 Bird Species Migrate Across a Map of the Western Hemisphere