Incubation lasts about 14-16 days--perhaps as long as 21 days in cool weather--during which time the female Ruby-throated Hummingbird is on the nest for about 50-55 minutes out of each hour. When the chicks hatch, they are about 2cm long, altricial (naked), and with very short bills. It may seem like the wrong time of year, but hummingbirds have begun nesting in Southern California. Large numbers of hummingbirds, especially Anna’s to the north and Allen’s to the south, are likely to be found in good numbers in hummingbird-friendly yards year-round. Incubation can be between 12 and 15 days, tack on a couple more days if the temperatures are cooler. Now the rest is up to the female, while he waits for more ladies to come by. After the second egg is laid, incubation begins. Hummingbird Breeding. In the Eastern United States and Canada mating of the Ruby-Throated Hummingbird begins in early spring upon return from their remarkable migration from Mexico and Central America. Most MALE hummingbirds found in California have gorgets (flashy throat patches). Friday, November 21, 2014. Most species are mature when they are just a few months old. This is one of the two common nesting hummingbirds in northern California gardens (Anna's is the other). They typically have breeding grounds that they return to year after year. The incubation period for a hummingbird nest varies from 11-22 days depending on the species and climate, but brooding periods of 14-18 days are most common for hummingbirds that breed in North America. The following 14 hummingbird species have been reported in California. Hummingbird lovers on the West Coast from California to British are also fortunate. Mating is a very interesting time to observe the behaviors of the Hummingbird. Female hummingbirds build the nest, sit on the eggs and care for the chicks without assistance from … A close relative of the Rufous Hummingbird, Allen's has a more limited range, nesting mostly in California. Migrating hummingbirds might arrive as early as January or February and usually leave in October. The mated female will lay to navy bean sized eggs usually two days apart. Here hummingbird nesting season runs late October through early June. In the western United States other species such as the Anna’s Hummingbird start to mate in late December and early January until March and April. In the furthest northern reaches of hummingbird ranges, the birds do not arrive until late spring or early summer. Hummingbird nesting season starts early in Southern California. In the central Canadian range of the calliope hummingbird or the Alaskan territory of the rufous hummingbird, you can wait until mid-May or very early June to put out hummingbird feeders. The season for breeding varies based on the climate in that given region.