By Gail Cochrane

Liberty Wildlife Volunteer

In December many humans attend holiday parties, string glittering lights and draw up gifting lists. In the parallel universe of nature however, there are a few species of wild birds making equally fevered preparations for something a bit more serious, mating season. Some desert species have found it advantageous to breed in the winter months, and experts see the season getting earlier every year.

Great horned owls are among the most conspicuous early nesters, hooting incessantly at dusk and in the early mornings, advertising their territories and wooing mates. It’s a bit of a misnomer to call this impressive predator a nester though, as great horned owls generally don’t build nests. Instead, they may make use of nests built by other species, such as red-tailed hawks. The hawks won’t be thinking about nesting for another month, so it’s an advantage for the GHOs to move in early.

In addition to pre-built hawk nests, these owls find cutbacks in banks, high fronds of palm trees, or large cavities in trees perfect locations for laying eggs. In urban and rural areas man-made structures often provide what seems to be the ideal nesting ledge. In dense areas these locations may lead to trouble when the fledglings begin “branching”. Great horned owl fledglings get adventuresome and start pushing and shoving a bit in the nest as they grow, often ending up on the ground.  The parents continue to feed and guard them during this awkward stage, but if there is a busy street or other hazardous situation nearby, a baby owl may require rescue.

Great horned owls mate for life and hold the same territory year after year if possible. Some live in the same area twenty years or more. Courtship begins in late November or December, with the two owls bowing to each other and hooting duets. The male brings tasty morsels to the female in attempts to further impress. Eggs are laid sometime between January and March. The female stays on the eggs and incubates while the male hunts.

Great horned owls are top notch hunters, known as tigers of the sky, but it takes quite awhile for the youngsters to learn to master flight and predation skills. Even after they are flying and hunting on their own the juveniles remain in the same territory with the parents. In November or December they finally set out to establish their own territories, right about when mating season is underway again.

Another December nester falls at the opposite end of the size spectrum. Anna’s hummingbirds are known to be the earliest of nesters. This tiny bird engages in dynamic courtship displays, with the male hovering, giving a buzzy song, then shooting high in the sky before diving steeply back toward the female. He may also zoom back in forth in front of her, impressing his potential mate with his stellar flight abilities.

Anna’s that winter in cold weather areas benefit from the extremely well insulated nests they build. Temperatures inside the nest can be 40 degrees warmer than outside. This keeps the eggs warm and helps the female conserve energy. Within two weeks of hatching a baby hummer has grown a downy coating of feathers that allows it to maintain its own body temperature.

Winter flowers provide nectar and the season’s insects are an important protein source for the babies. The female must provide ample fuel to power the quick growth and feather production of her young. The warming days of spring signal the end of breeding season for this species in our region. Other winter nesters begin the mating process in January and February, including Harris’s hawks, red-tailed hawks, barn owls, and members of the dove family.

Sources:  Bird Nests and Eggs by Pinau Merlin

Audubon.org/Field Guide

Previously published in 2015.