Thanks to the wonders of webcam technology, people from around the world are watching the owl nest at Ellis Bird Farm. If you haven’t yet had a look, check out the ustream link on our homepage www.ellisbirdfarm.ca.
The female owl (named Ellie by viewers) has sat on her nest through very miserable weather conditions. We have our fingers crossed that her eggs are still viable and that her young will hatch sometime around the middle of April.
Great horned owls are the most common and widespread owl species in Alberta. As denizens of the night, their eerie hoo-hoo-hoo hoo-hoo-hoo is a classic sound of the dark.
They are strong fliers, are adaptable to a wide variety of habitats and prey, and have few natural enemies. Apparently their sense of smell is poorly developed, since skunks are a relished menu item (along with bats and other small mammals, birds and even reptiles and amphibians).
Great horned owls were so named because their feathered ear tufts resemble horns. These ear tufts don’t have anything to do with their hearing, but are thought to assist with camouflage (the tufts can resemble broken branches). Their mottled brown colouration also provides excellent camouflage.
Camouflage is just one of the great horned owls’ many adaptations.
They are also able to fly in complete silence because their feathers are covered with small scales and the leading edges of their primary feathers have small comb-like bristles that serve to break any sound-generating turbulence.
Their large eyeballs, which are fixed in bony tubes, are well adapted to see in very low light but require the birds to move their heads around to see. (Owls cannot spin their heads completely around, but can rotate them up to an impressive 270 degrees.)
Their ears, which are actually large slits on each side of their skull, are offset so one is higher than the other. Sound reaches each ear at a different angle, effectively allowing them to hear in 3-D.
Great horned owls are early nesters, often spotted sitting in late February and early March. They typically lay one to five eggs at two-day intervals and the female (who is about 20 per cent larger than her mate) begins to incubate as soon as the first egg is laid. In a year of plenty, all the young may survive. In times of shortage, the youngest chicks perish from starvation.
The eggs are incubated by the female for about a month, then both parents share the task of feeding the nestlings. The young are ready to climb around outside the nest at about five weeks of age. They stay in the area for about another month, then remain dependent on the adults for several more months. Young great horned owls don’t usually move more than about 80 km from where they are hatched.
Myrna Pearman is the Biologist/Site Services Manager of Ellis Bird Farm. She can be reached at firstname.lastname@example.org