Skip to content
Bird Migration Forecast map 2023

By September, fall’s bird migration is in full swing. We can find shorebirds and ducks arriving at Fern Ridge and other waterways. We can see the Vaux’s Swifts at Agate Hall, as well as other chimneys around the area. The raptor migration can be observed by watching the skies as several species soar south, moving on southerly air currents.

For autumn birding locally, we have the return of mountain birds to the lower elevations. Some birds migrate through, heading south; others simply move into lower altitudes like the Willamette Valley for the winter. This is true of the Belted Kingfisher, Varied Thrush, Northern Flicker, Pacific Wren, the two kinglets, and Harlequin Ducks (who return to coastal waters). We also see the return of some of the northern-breeding birds, such as Golden-crowned Sparrow and Fox Sparrow, plus many ducks and shorebirds that will remain in the Willamette Valley until next spring.

Many smaller Neotropical bird species (70% to 80%) migrate at night, affording them some protection from predators. The stars and the moon aid night-flying birds’ navigation. Free of daytime thermals, the atmosphere is more stable, making it easier to maintain a steady course, especially for smaller birds such as warblers that might fly as slowly as 15 miles per hour. We often are unaware of the huge number of birds passing overhead at night, unless we are outside and hear their contact calls as they fly overhead in loose groups.

A relatively new and fascinating resource for learning about these night migrations is a website called BirdCast.

About BirdCast: “Beginning in 2018, after many years of research and developments in machine learning, cloud-based computing, and big data analytics, the BirdCast site began to feature migration forecasts that predicted how many birds would be aloft over the continental US, plus live migration maps that reported how many birds actually took flight. These bird migration maps represented the culmination of a 20-year-long vision,” [as well as] “the beginnings of new inspiration for the next generation of bird migration research, outreach, education, and application. BirdCast applies weather surveillance radar to gather information on the numbers, flight directions, speeds, and altitudes of birds aloft in order to expand the understanding of migratory bird movement.”

For a review of these tools and the 2023 season see this article: On the BirdCast website, one link option allows you to select your local area (Lane County) and view a dashboard which keeps an updated tally of numbers and species that are migrating through after dark. See the Lane County info here. You can look at historical and forecast data as well as Real Time data on a particular day! This opens a new world of bird life data to help us learn about these wonderful animals and their nighttime migrations.

The transitions to fall and winter help us to track the pulse of the natural world. We need to remember the rhythms of the earth moving around the sun, and how we depend on this wonderful planet, our blue-green Earth. It is home to birds, to humans, and every living creature that depends upon the integrity of the Earth’s systems to survive.