Tag Archives: owlets

Early Birds Get More than the Worm

In the wild, February and March may seem like the worst time for a bird to raise a family, with challenges including frigid temps, sleet, wind, and snow. But this is no ordinary bird, this is a great bird—a Great Horned Owl (Bubo virginianus). These large, thick-bodied raptors- weighing in at 2.5 to 5 pounds with 4 ½ to 5’ wingspans –  are one of the most widespread owls in North America and have plenty of ‘don’t mess with me’ moxie. They have a very diverse diet, including small mammals, rabbits, geese, herons, amphibians and reptiles, skunks, porcupines – and even other raptorial birds. It is this adaptability and tenacious behavior that gives them a leg up on surviving tough conditions.

Great Horned Owls are among the earliest birds to breed each year, with males staking out territory from other males beginning in October. Most Great Horned Owls mate for life and every autumn they reestablish their bonds by loudly calling to each other. Like many birds, they have a range of vocalizations. Their classic hoot is unmistakable, a deep slightly muffled resonating “hoo-h’HOO–hoo-hoo” call with the female’s voice slightly higher in pitch than the male’s.

While establishing their territory they will seek out a suitable nest. They don’t build their own– instead, they use abandoned real estate like an old Red-tailed Hawk nest or a hollowed tree cavity, even a cliff ledge will do.

Great Horned Owl family
Great Horned Owl, at the nest with her Owlets

When January arrives the parents-to-be will be settled in and ready to start a family. The female will lay 1-4 eggs and incubate the eggs for 30-37 days through all kinds of weather.  Only the female can incubate the eggs as she has a featherless patch on her abdomen called a “brood patch,” an area that has many blood vessels and is very efficient at transferring her body heat to the eggs. While she is incubating and brooding the young chicks, the male will hunt for them, but if the food he provides is insufficient she will also hunt for the family. Great Horned Owls are large birds and it takes owlets longer to grow than say a robin and longer to develop and master complex skills.

Great Horned Owl Feather
Great-horned owl feathers have a velvety texture and combined with tiny serrations along each feather edges called flutes which muffle their wing beats allowing owls to silently swoop down on their prey unnoticed.

Nesting early is a risky move but there are definite advantages. By day 45, the young are fully feathered and capable of flight and by the time spring arrives, these youngsters are ready to practice their main craft– hunting.  Not only are temperatures milder but there is now an abundance of young inexperienced prey animals, such as rabbits, mice, squirrels and chipmunks who are also venturing out on their own. These predators can now hone their flying and hunting skills under ideal conditions all because their parents were early birds.

Owl Talons
When clenched, an adult Great Horned Owl’s talons lock down like a ratchet and require a force of 28 lbs. to pry them back open.
Tiger Owl Eye
Owls have huge eyes compared to their body size– larger eyes are able to take in more light which is picked up by their rod- and cone-shaped photoreceptors. Rods allow them to see well in dim light, but colors, not as well. Cones help distinguish colors but only when our surroundings are well lit. Humans have about 200,000 rods per square millimeter while owls have close to a million rods per square millimeter. This is then magnified by the owl’s tapetum lucidum or ‘eyeshine,’ a feature humans do not have. This layer of tissue located behind the retina reflects all available light to those photoreceptor rods and provides superior night vision.

For More Information

Cornell Lab of Ornithology https://www.allaboutbirds.org/guide/Great_Horned_Owl/id

Audubon Guide to North American Birds https://www.audubon.org/field-guide/bird/great-horned-owl