The ruby-throated hummingbirds have begun their feeding frenzy by this time of August.

The newborns have joined the adults in our gardens and at feeding stations, and because their fall migration period begins in early August, we in the southern part of Minnesota begin to notice more of them, always by mid-August.

You can help feed them.

Set up several feeders, widely spaced, as there are twice as many of these tiny birds. Plain sugar water for feeders is made up of one cup of white sugar dissolved in four cups of water. Do not add food coloring.

John James Audubon called hummingbirds "glistening fragments of the rainbow," and most birders agree that they're the gems of the bird world.

Some observers say that in mid- to late August hummingbirds are seen in the gardens more than at feeders.

The Henderson (Minn.) Hummingbird Hurrah is held the third Saturday of August (that's this Saturday) to celebrate Minnesota's smallest bird. Activities include banding and gardening for hummingbirds. The banding sessions are taught by hummingbird biologist Don Mitchell. Mitchell recaptured a female ruby-throat in his Red Wing yard six years after banding it. She was an adult when originally banded, so she was at least 7 years old. The bird's average life span is 4 to 5 years.

Jim Gilbert's Nature Notes are heard on WCCO Radio at 7:15 a.m. Sundays. His observations have been part of the Minnesota Weatherguide Environment Calendars since 1977, and he is the author of five books on nature in Minnesota. He taught and worked as a naturalist for 50 years.