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ST. LOUIS, Mo. – Hummingbirds in the northern United States will start heading back to Mexico soon. You’ll want to keep your hummingbird feeder out until Thanksgiving to help fuel their incredible journey.

The ruby-throated hummingbirds seen in Missouri will start their southward journey in August and September. The Missouri Department of Conservation says that people should expect to see more of them in the state during these two months.

Students in Norfork, Arkansas Predict the Arrival Date of Ruby-Throated Hummingbirds in their Migration Path North

The hummingbirds tend to linger at feeders before starting their trip. You’ll see more of these small birds because more young birds have been added to the population.

You may find some semiconscious hummingbirds on branches and windowsills as the fall weather cools. Their body temperature drops as much as 20 degrees on cold nights and they may slip into a hibernation-like state. The warmth of your hand is usually enough to revive them.

The Missouri Department of Conservation says that you may spot some of the late-migrating western species like the rufous hummingbird through November. Although the sighting may be rare.

Changes in daylight duration and declining numbers of flowers, nectar, and insects can trigger the need to migrate. They can travel as much as 23 miles in one day and spend winters in Central America or Mexico.

After leaving the Midwest the birds will gather in Florida, Louisiana, and Texas in preparation for the final push. The birds will then fly over the Gulf of Mexico or overland to reach their final destination.