I always expect ruby-crowned kinglets and yellow-bellied sapsuckers to show up in my yard on the day of the Kenduskeag Stream Canoe Race, accompanied by pine, palm and yellow-rumped warblers.
They all arrived two days late this year.
I can’t blame the birds for choosing not to arrive on Saturday. Anyone who paddled in the canoe race will agree that it wasn’t the best day for travel. Sunday’s gale didn’t help much, either. Fortunately, the winds died off overnight.
Sure enough, a small wave of migrants arrived on Monday.
I did some birding in Waterville on the Thursday before the race, and all my expected birds had made it that far. Thanks to weather delays, it took them three more days to fly 50 miles farther north.
It was a stark reminder that migration is both orderly and chaotic.
Nocturnal flight is no longer invisible thanks to BirdCast, a joint project of the Cornell Lab of Ornithology, Colorado State University and the University of Massachusetts at Amherst. Migrating birds show up on weather radar, so since the turn of the century, BirdCast has watched migration in real time via radar.
It now shares the results and makes migration predictions online.
For instance, on the night those northbound birds headed for my yard, radar estimated that 3,500 birds crossed into Penobscot County. Many more crossed into our region last week, when the overnight winds and weather conditions were more favorable.
Tracking data like this is available anywhere in the country. The consortium estimates bird flight counts from coast to coast, as measured by 143 radar systems.
At first glance, BirdCast is merely a curiosity. At second glance, it quickly becomes apparent that it’s much more than that.
With a quarter century of data now packed into a warehouse-sized computer somewhere, scientists can accurately predict how big the migration will be anywhere, on any night, under expected local weather conditions.
The morning after a big flight movement can be exciting. Nocturnal migrants settle down at daybreak wherever they are. It’s possible to forecast when those wild spring mornings will happen, giving birders advance notice of when to call in sick for work.
Take a third glance. The bigger picture of bird migration boggles the mind. BirdCast predicted 209 million birds would move across the United States last Monday night.
That kind of information may help address a long-time predicament.
Ever since humans started building things skyward, birds have been crashing into them. It’s one of the three major reasons bird populations have plummeted by 3 billion since 1970. The other two are habitat loss and outdoor cats.
It would be bad enough if they were colliding in the dark, but it’s apparent that birds can be drawn to the light, making collisions more frequent.
On a big night, more than a billion birds can be in the air over America.
What if on those nights, we just turned off any lights we didn’t need? Skyscrapers and towers would suddenly kill fewer birds, and save energy, too.
It’s not a fantasy. “Lights Out” initiatives are already underway in 30 cities.
It only takes three weeks for most migrating birds to pass through a region. Any inconvenience would be short, infrequent and maybe a teensy bit exciting.
BirdCast has built a forecast model for 1,000 American cities.
When the weather radar data is combined with the huge database of records already in eBird, another project sponsored by the Cornell Lab and its partners, we get a much more detailed version of what’s going on up there in the dark.
Radar can only track the mass of birds in the air, not specific species. When combined with eBird data, we can ultimately track both.
We’ve always known that southern states experience the first wave of migration, as neotropical birds migrate northbound across the Gulf of Mexico, excuse me, the Gulf of America. Texas and Florida are getting peak migration flows right now.
The wave won’t peak in Maine until the last half of May. But with all this new data analysis, we have a much better idea of the peak dates for individual species, including where they’re coming from, where they’re passing through and where they’re going.
This enhanced analysis has been built into yet another project called BirdFlow.
Earlier this month BirdFlow launched a YouTube video that graphically shows the movements of a billion birds from Argentina to Canada. Look up Spring Bird Migration Data Visualization, and prepare to have your mind blown.
