Growing up in Boston, my mother, with four of us underfoot, was determined to convince us that the best times were spent outdoors, no matter the weather. She would describe all the wonderful things happening in our backyard, then firmly herd her brood out the back door. She may even have locked it behind us—though my memory is not entirely certain.

Both of my parents worked: my mother taught in the Boston Public School system, and my father was the local doctor. We lived on a corner lot with plenty of yard to explore, full of trees and shrubs, skunks, rabbits, snakes, and birds. There was always something to occupy us, and bird watching quickly became one of my favorite interests, along with gardening—both lifelong joys. During one of our rambles around the yard, my sister Jane and I found a blue jay with an injured wing. My father placed it in a shoe box, fashioned a tiny splint, and nursed it back to health. We were delighted to see it recover, and when the day finally came, we released our jay in the front yard and watched as it soared into the trees.

When the children in our family were young and came to visit, we always took part in the Great American Bird Count and the Christmas Bird Count. They would sit at the kitchen table, looking through the storm door at the bird feeders, survey sheets in hand, identifying, counting, and recording every bird they saw. Later, as college students, both took ornithology courses, and now, as adults, they know far more about birding than I do.

Most people know that birds migrate at this time of year, but few realize the enormous numbers involved, how fast they travel, or the patterns they follow. Recently, I discovered BirdCast, a remarkable app developed by Cornell University’s Laboratory for Ornithology. The Migration Tools are active from August 1-November 15^th and from March 1-June 15^th. Birds typically begin migrating thirty to forty-five minutes after sunset, flying between 3,000 and 10,000 feet above the ground.

BirdCast uses existing weather radar to track these nocturnal movements and presents the data through graphs, maps, and local summaries. For example, last night—from sunset to sunrise, still early in the migration season—5,543,100 birds passed over Sullivan County. The app’s location dashboard shows daily migration speed, direction, and volume for specific areas. What might these unusually high numbers mean? Since peak migration usually occurs in mid- to late October, they may suggest that winter weather will arrive several weeks earlier in Sullivan County this year. I also noticed that no hummingbird stragglers (females and young birds) have visited my feeder in the last few weeks.

BirdCast’s recent data analysis indicates that, as global temperatures rise, many species are shifting their migration timing earlier so their arrival better matches peak food availability, such as insect hatching.

The free BirdCast app has also grown over the years, adding helpful features such as live migration radar, forecasts, bird-protection information, email alerts, and Merlin Bird ID, a free companion app that can identify birds by sight or sound. It is a long way from children sitting at the kitchen table with pencils and bird-count sheets, but the wonder of it all remains the same.

To download the free BirdCast app go to BirdCast.org.