Where did they go?
Have you had hummingbirds visiting your feeders in the spring only to have them suddenly disappear? Don't worry. They haven't really left. They're probably just taking care of their little baby hummingbirds.
Female hummingbirds spend time sitting on their nests and then, once the babies hatch, the new moms are busy looking for insects to feed the hatchlings.
Although hummingbirds love and depend on nectar from flowers and feeders, their feeding needs change when newborns arrive.
A certain part of a hummingbird's diet always consists of insects. They eat tiny little bugs. Those bugs provide protein that the baby birds need, so hummingbird parents will spend more time looking for insects and less time visiting nectar feeders while they're raising their young.
Male hummingbirds are also pretty territorial (particularly the Ruby Throated Hummingbird). You've probably seen hummingbirds chase each other away from feeders. This territorial behavior can get stronger during the spring nesting season. Placing mulitple feeders might help with this, but sometimes one very active male hummingbird will do his best to defend all of your feeders.
Once the babies have fledged the nest, your hummingbirds will most likely return to your feeders. You'll see more females again and you'll probably see some new young hummers too!
So, be sure to keep your hummingbird feeders cleaned and filled with fresh nectar even if you think the hummingbirds have left. The hummers will be back. The warm summer months are when feeders are usually most active.
Note: For most parts of the United States, hummingbirds won't stay year-around. They'll leave in the fall and come back the next spring. Learn more about hummingbird migration.
You're seeing fewer hummingbirds at your feeder. Should you worry? (from All About Birds blog)
Where did my hummingbirds go? (from Wild Birds Unlimited)
What do hummingbirds eat? Types of hummingbird food. (from About.com)