Humming birds are an interesting group of birds. They can see farther than humans and have better hearing, but have no sense of smell. It is no surprise that their nesting habits are interesting as well. Females do all the work, from building a camouflaged nest to caring for her tiny hatchlings.
In the humming bird world males have nothing to do with preparing for or taking care of hatchlings. Females select the nest site, build the nest, tend the eggs, and care for the hatchlings all on their own. But it isn't because the male doesn't want to help, she just won't let him. In fact males are frequently chased away from nesting sites.
A hummingbird's nest is approximately two inches in diameter and built in a tree with adequate cover. Of course there is variation among species, but in general the nests are around this size. Materials will vary depending on species and location but plant fiber, plant down, lichen, and spider silk are commonly used.
Incubation lasts for around two and a half weeks and hatchlings stay in the nest for around three weeks. A ruby throated humming bird, for example, lays two bean sized eggs and will incubate them for 10 to 14 days. To help shield her eggs from the elements, the ruby throated humming bird will cover her nest with broad, green leaves.
Occasionally females will return to a nest they used the year before. But rather than using the same nest, they will build a new one on top of the old one.
Hatchlings spend about three weeks in the nest. The female hummingbird feeds them regurgitated insects instead of the nectar she eats. The hatchlings of Anna's hummingbird are fully covered with down at about six days. After they begin to fly, they will periodically visit the nest for about two weeks until they are completely independent.