Tracking migration
Spring bird migration is underway. You can remove some of the guesswork about days with boom or bust potential by using a radar-based bird-tracking site.
Live bird migration maps are published daily at birdcast.info. Color-coded maps created in real time show you bird movement throughout the continent. Just bookmark birdcast.info.
Warbler 101
Roger Tory Peterson called them "confusing fall warblers" because of their drab plumage. For backyard or casual birders, identifying brightly colored spring warblers can be a challenge, too.
Cornell Lab of Ornithology can help you with a 15-hour online identification class. There are short training videos, still photos for more practice, information on clues provided by bird movement and song, free identification posters you can download, and more.
Price is $98. The course can be taken and completed at your own pace.
The address is academy.allaboutbirds.org.
Nature's stars
A daily brief nature film is offered at website nature365.tv by famed Minnesota photographer Jim Brandenburg. A native of Worthington and resident of Ely, his worldwide work has often been published in National Geographic magazine. Birds often are featured.
Vulture trivia
The recent column about turkey vultures produced several responses from readers, including this note from Carrol Henderson, retired former superintendent of the nongame wildlife program of the Minnesota Department of Natural Resources.