When I checked the weather radar this morning, I could see that last night’s storm had moved off to the east. Then, just after sunrise, green and yellow speckles began appearing around major cities. Here’s a small piece of what I saw on the Chicago Tribune‘s regional radar this morning:
Those speckles weren’t rain — they were birds! Big flocks birds took off just after sunrise, using strong southwest winds to help them on their way.
What kinds of birds were they? The radar can’t tell. To find out, I’ll watch the skies this morning, then read reports on the IBET birding e-mail list later this afternoon.
Nature Note added 8:40 p.m. on Tuesday, February 10:
We spent much of the day trying to figure out which birds we saw on weather radar this morning. The window by my computer was open all day; I took an hour walk through southwest Oak Park late this morning; I visited Columbus Park to check the goose flocks mid afternoon; and we all watched the skies while running errands later this afternoon. All we saw and heard were bird species that have been in our area all winter long.
Other birders had more luck and reported what they found on IBET and the Indiana list. Two birders reported Greater White-fronted Geese flying north in Illinois, one from the southwest corner of our county and one from the next county north. There also were reports of newly arrived Red-winged Blackbirds along the Chicago lakefront and at feeders in Chicago suburbs and Indiana. And there were reports of Canada Goose flocks moving north (the White-fronted Geese were traveling with these flocks). It’s a good bet that these geese had wintered further south.
So, this morning’s radar speckles included geese and blackbirds. We hope to see these newly arrived species in our neighborhood over the next few days.
You can study bird migration using radar images from WeatherUnderground (the source of the Tribune‘s images) and the National Weather Service radar website. But be warned — bird flocks move when the winds are right, usually before or after fronts pass through (depending on which way birds want to go). Peak movements in the spring are often at night, before a cold front, when winds are from the south.
For a more detailed explanation of birds and radar, try the New Jersey Audubon website.
The Badbirdz – Reloaded blog also includes a primer on using weather radar to track bird migration.