A ruby-throated hummingbird is a joy to watch.

Minnesota's smallest bird. A summer resident. The only hummingbird that nests in the state. The bird's appearance is unmistakable — metallic green above and white below. It gets its name from the ruby-colored throat of the male that actually looks black in some light conditions. These birds are only about 3 inches long, with an average weight of 3.4 grams. It would take about 130 of them together to weigh a single pound. Their top flight speed is just under 30 miles per hour.

These tiny hummingbirds burn up so much energy that they're forced to eat almost constantly, and keep right on feeding into the twilight after most other birds have begun roosting. Their food consists of nectar and small insects. They will come to sugar-water feeders. I like to use a mixture of one part granulated white sugar dissolved in four parts water to lure them close enough so we can hear the humming sound from their rapid wing beats. Rinse your feeder with water and scrub with a stiff brush to remove any dirt or sticky spots to help halt fermentation and mold growth. Do not add food coloring, some of which is not safe, or honey. Hummers are drawn to colors, so use a feeder made with colorful materials.

Survival for a hummingbird depends on fast movements — and courage. They can hover, move backward, and dart forward at high speed to outmaneuver other birds. They get aggressive in defense of territory and will go after much larger birds such as crows and blue jays, using their long needle-sharp bill as a dagger.

Jim Gilbert's Nature Notes are heard on WCCO Radio at 7:15 a.m. Sundays. He taught and worked as a naturalist for 50 years.