Some people may catch a fleeting glimpse of one hovering near backyard flowers. Others possibly hang out at feeders and watch a handful of them buzz around sugar water for a few days. But the majority of Houstonians are unaware of the thousands of tiny miracles zipping through and past our city.

They are ruby-throated hummingbirds — millions of them — on their annual migration.

After leaving their breeding grounds — some from as far as central Canada — they beat on tiny wings all the way to Central America, right through Texas. Before reaching the tropics, where they will spend the winter, they must cross one of the greatest obstacles en route: the Gulf of Mexico. During fall, the majority of birds — especially with the young of the year flying south for the first time — circumvent the Gulf of Mexico and follow the coast into Mexico.

Throughout September, ruby-throated hummingbirds literally pile up along the upper Texas coast, circling flower patches and swarming hummingbird feeders, eagerly lapping up as much sugar water as will fit. Some make it a multi-day pit stop, putting on fat reserves for the long overwater flight.

Humming along with the birds

The Gulf Coast Bird Observatory (GCBO) in Lake Jackson offers an unparalleled opportunity to witness the spectacle firsthand.

Tucked away at the end of an unprepossessing dirt drive off Highway 332, the observatory invites visitors to observe nature. The open grounds of the sanctuary are planted with a myriad of flowers, particularly shrimp plants, favored by hummingbirds. Willow-lined ponds provide food and shelter for other wildlife.

Each year, the GCBO hosts an event open to the public, appropriately named the Xtreme Hummingbird Xtravaganza Open House.

We arrived bright and early at 8 a.m., and the small parking lot was beginning to fill. Out on an open lawn, dozens of hummingbirds hovered around full feeders — some perched on telephone wires, others in nearby brush. Birds chased each other about, defending sugar in whirrs of wings and chatter.

Banding and adopting the birds

For several years, researchers at the bird observatory have banded hummingbirds. The process is quite simple, quick and painless.

Volunteers watch the numerous feeders and release a trap door that closes behind an unsuspecting hummingbird that ventured close to the feeder. A trained researcher frees the bird from the trap, puts it in a net bag and carries it to the banding station.

Waiting its turn, the bird is banded with a tiny, lightweight aluminum band that has a unique number engraved. The bird can be identified by that number if it is ever recaptured, thus yielding data on age, survival, migration route and more.

Before being released, the trained bird bander blows lightly on the belly feathers with a straw to check the fat deposits, an indicator of the bird’s health and vigor. Then it is quickly weighed and its sex determined. Males sport the namesake ruby-colored gorget, while females have a whitish throat and white tail tips.

Visitors can adopt a hummingbird for a fee. The money raised is used for conservation projects throughout Texas and in the tropics further south. Adoptive parents get to hold the hummingbird for a moment and feel its heart, which beats over 1,000 times in a minute. Some birds will sit still in the hand for several minutes before buzzing off.

The local research shows that birds fatten up considerably and have often gained weight within a few days. The 500 mile flight across the Gulf of Mexico requires over 20 hours of nonstop flying on wings that beat roughly 50 times per second. There is no place to rest.

Once ruby-throated hummingbirds arrive in the Yucatán, they migrate further into southern Mexico — and some all the way into Panama, at a slower pace.

Come for the hummingbirds, stay for the auxiliary attractions

In addition to the hummingbirds, which are no doubt the stars of the show, local naturalists give talks on gardening and photography. Several reptiles are on display, and observatory staff teach visitors the basics of wildlife watching.

Two miles of hiking trails allow visitors to leave the crowd behind and follow quiet paths winding through oak forest. Others can take a seat at the platform overlooking Buffalo Bayou fringed by trees draped in Spanish moss.

Come out this Saturday and enjoy a morning of hummingbirds, science and wildlife.