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Great Horned Owls
December 16, 2013
I think it is safe to say, we are going to have a White Christmas in Michigan.
Besides the storm fronts that move through, The lakes kick up several inches and yes, feet of the white fluff.
The Great Lakes are like a two edged sword.
While they keep us 10 to 15 degrees warmer (fahrenheit) than Wisconsin and parts west, they often blanket the ground with snow.
Sometimes, days on end.
The warmer water and cold air also create cloud cover, where the sun is blocked out most of the time this time of year (or so it seems).
Anyone that lives near the Lakes can attest to that (especially eastern and southern locations).
Yes, the ducks come in flocks of 50 or more every evening for a feed.
Cracked corn is on the menu, still it adds up.
Bobo our Lovebird, continues his struggles.
December 6, the vet put a new collar and a hoop around his neck.
He was so stressed, that Karen insist I remove it.
He went right back to ravaging himself, so I modified it (made it smaller), and put it back on.
Bobo doesn't like it one bit, but is able to move around.
He goes back to the Vet this Friday for another look.
A Bit of History on the Christmas Bird Count:
Prior to the turn of the century, people engaged in a holiday tradition known as the Christmas "Side Hunt":
They would choose sides and go afield with their guns; whoever brought in the biggest pile of feathered (and furred) quarry won.
Conservation was in its beginning stages around the turn of the 20th century, and many
Beginning on Christmas Day 1900, ornithologist Frank Chapman, an early officer in the then budding Audubon Society, proposed a new holiday tradition-a "Christmas Bird Census"-that would count birds in the holidays rather than hunt them.
So began the Christmas Bird Count.
Thanks to the inspiration of Frank M. Chapman and the enthusiasm of twenty-seven dedicated birders, twenty-five Christmas Bird Counts were held that day.
The locations ranged from Toronto, Ontario to Pacific Grove, California with most counts in or near the population centers of northeastern North America.
Those original 27 Christmas Bird Counters tallied around 90 species on all the counts combined.
The bird count is December 14 thru January 5, if you plan to count.
(Courtesy of the Audubon society.)
This week's topic is the Great horned Owl.
Great Horned Owl
I am blessed enough to have at least one residential pair of this magnificent bird.
Not only do I see them from time to time, but this is the time of year to hear them as well.
While these birds mate for life (such as it is), they go through a courtship every year to start the courting and mating season.
Part of the ritual is hooting back and forth during the hours of darkness.
It is probably the most recognized owl in North America and for sure the most aggressive owl.
A few of you are blessed enough to host these large birds of prey and I'm sure you can tell me a thing or two about them that I wont mention here.
From a well known nursery rhyme
"The Wise Old Owl"
A wise old owl lived in an oak
The more he saw, the less he spoke
The less he spoke, the more he heard
Why can't we all be like that wise old bird?
Great Horned Owl (Bubo virginianus):
The Great Horned Owl was first seen in the Virginia colonies, so its species name was created from the Latinised form of the name of this territory (originally named for Queen Elizabeth I, the "Virgin Queen").
The first published description was made in 1788 by Johann Gmelin.
Large in stature and magnificent in flight, the Great Horned Owl is a beautiful bird that is commonly heard, though rarely seen.
Already well-known as symbols of wisdom and warnings of impending doom, there is much more to the Great Horned than the myths and legends that surround owls.
The Great Horned owl, the most powerful of the common owls, is a visually stunning creature.
It is distinguished by its large size, and the feather tufts on its head that resembles horns (and often mistaken for its ears).
Their big, yellow eyes are often compared to those of a cat, and are amplified by the orange facial disk outlined in black.
The coloring of the body – hues of browns and grays with black bar markings, make the owl's white throat very prominent.
Great horned owls are 18 to 25 inches in length.
Also standing out is the span of its great wings, approximately 4 - 5 feet from tip to tip.
As with most birds of prey, the female is larger than the male.
The female is often 20% to 30% larger than males.
Males can weigh 3 pounds plus while the much larger female can top the scales at 4 to 5 pounds and a few ounces more.
Great horned owls will aggressively protect their territory from other owls and have been known to take on Osprey successfully.
Though eagles and owls try to avoid each other, Great horned owls and eagles will tangle from time to time.
Don't get to close to the nest sight, or you may be wearing some stitches later on.
Yes, they can be that aggressive.
Owls are mostly nocturnal creatures but can sometimes be spotted in the late afternoon or early morning.
Like most owls, Great Horned Owls have keen hearing and sharp vision in low light, both adaptations for hunting at night.
An owl can only not see what is right in front of them, but it is able to turn its head over halfway around to see what is behind them.
Because an owl's eyes are fixed (they can't roll them, look out of corners or move them up and down), an owl must have the ability to turn its head.
An extra vertebra (14 in all) allows the owl to turn its head 270 degrees right or left and this gives the appearance that an owl can turn its head all the way around.
Owls have a third, opaque eye membrane, called the nictitating membrane.
This membrane helps to clean the eye of material and protect the eye from the brightness of day or foreign objects at night.
Pupils can also dilate as fast as we can turn on and off a light (I've seen this with captive owls).
Their beak, small and hooked, does not interfere with their binocular vision which helps determine the distance of their prey.
Owls can also catch their prey by using their sense of hearing.
Their large ears are covered by special feathers and are located behind the facial dish feathers.
These feathers allow the owl to hear even the smallest sound (like a mouse squeaking) up to 900 feet away.
Can you only imagine how "Nature" has equipped these birds?
Their ears are located on the sides of the head, but are off-set, not symmetrical like human ears.
The openings of the ears are slightly tilted in different directions - often the right ear is longer and set higher up on the skull.
Plus, owls have soft feathers that surround the openings which they can spread to make a funnel for sound to enter the ear.
This enables the owl to use "triangulation" to pinpoint the source of a sound, when the prey can not be seen.
By tilting or moving their head until the sound is of equal volume in each ear, the owl can pinpoint the direction and distance of the sound.
Studies have shown owls hunting in pitch dark rooms using only their hearing and having very successful kill ratios.
For hunting at night, an owl could do this strictly by sound if there weren't obstacles in the way.
Talk about STEALTH.......
Owl feathers are soft, almost like polar fleece to the touch.
This helps to deaden the sound of air rushing over the feathers while the bird is in flight.
Also the front edge of the first primary or wing feather is toothed like a hand saw.
This helps wind pass over the wings and keep the bird's flight noiseless.
Several times I have watched these birds fly overhead and close enough to hear a fly over.
With owls, you can't hear a wing beat or rush of the wind as you would with other birds.
It wouldn't be easy to sneak up and catch prey at night if you were crashing around in the dark.
Owls are more of a perch and wait predator.
With this in mind, they are more inclined to glide than fly as well which calls for less wing flapping.
Like most birds, owls have four toes on each foot, .
Instead of having three toes in front and one in back, an owls outer toe is reversible.
It can rotate so that there are two toes in front and two in back.
This helps the owl grip a perch but also creates a bigger "mitt" when it swoops down to catch prey.
Great horned owls can stretch their toes and talons out to 4" by 8" area or almost the size of a human hand
This comes in handy as these powerful sharp talons come crashing into a target.
The large powerful claws not only increase hunting abilities, but also allow owls to catch and carry larger prey.
Sometimes 2 to 3 times the size or weight then the bird itself.
A four pound owl times 2 or 3......................
That is an 8 to 12 pound kill it can carry off.
How impressive is that?
Tests have shown that owl feet are so powerful, that it takes more than 28 pounds of pressure to open their feet.
Not only are they strong, but they can grab and crush as well.
Great horned owls do not breed until they are 2 years old.
Nesting season is in January or February, and possibly earlier, when the males and females hoot to each other.
You will hear two different pitches.
The male owl, while smaller in stature, has a lower pitched hoot.
You may hear this and somewhere nearby (in any direction), you will hear a higher pitched hoot--hoo-hoo-hoo , from the female.
Or, visa, versa.
When close they bow to each other, with drooped wings.
Mutual bill rubbing and preening also occurs.
They do not build a nest of their own but utilize the nests of other birds such as the hawk, crow and heron.
They may also use squirrel nests, hollows in trees, rocky caves, clumps of witches broom, abandoned buildings, or on artificial platforms.
They also use a variety of other nest sites such as cliffs, and the ground.
Trouble may begin when owls take over an Osprey or Eagle nest.
In some locations, Eagles and Osprey migrate for a short spell because of a food shortage from winter's cold and frozen waters.
The same time Great horned owls are house hunting.
They are extremely aggressive when defending the nest and will continue to attack until the intruder is killed or driven off.
Normally, two to four eggs are laid and incubated by the female and sometimes both parents only for 30-35 days.
Often the male will feed the female as she sits.
Hatchlings are fed by both parents.
As with many predatory animals, owls will lay more or less,depending on the food sources at hand.
Bounty means more eggs.
Lean times mean 1 or 2 eggs (fewer mouths to feed).
If a young owl falls out of the nest prematurely, the adult will feed it on the ground.
Young start roaming from the nest onto nearby branches at 6 to 7 weeks, when they are called "branchers", but cannot fly well until 9 to 10 weeks old.
They are fed for another few weeks as they are slowly weaned.
Families remain loosely associated during summer.
Adults tend to remain near their breeding areas year-round while juveniles disperse widely in the autumn.
Territories are maintained by the same pair for as many as 8 consecutive years.
However, these owls are solitary in nature, only staying with their mate during the nesting season.
Average home ranges in various studies have been shown to be approximately 2.5 square kms (1 square mile), but they will extend that range while hunting.
Again, research suggests that young owls remain close to home......... typically within a hundred mile range from their original home or nest.
It is common for Red-tail hawks and Great horned owls to occupy the same territory with little hassles from each other.
Because hawks hunt during the day and owls at night, there is no need to feel threatened about food sources.
Diet can consist of:
Turkeys, rabbits, woodchucks, mice, rats, squirrels, skunks (a skunk's worse nightmare), shrews, muskrats, weasels, pocket gophers, bats, ducks, quail, geese, heron, sparrows, grouse, pheasants, other owls, snakes, beetles, scorpions, frogs, grasshoppers, domestic cats and even small dogs.
Yes, my little fur kids could become owl food if I didn't keep an eye on them.
(Range Map to the left.)
With Great horned owls around here, the little fur kids aren't left outside, even on a leash without supervision.
If you have outdoor cats, Fluffy may come up missing one night.
Owls typically swallow their prey whole (small rodents etc.).
Several hours after eating, the owl’s stomach will form a pellet consisting of the fur, hair, exoskeleton and bones that will be regurgitated.
A long-lived Owl, captive birds have been known to live 29 to 38 years, and wild Owls up to 13 years.
Most mortality is related to man - shootings, traps, road kills and electrocutions.
The only natural enemies are other Great Horned Owls and, occasionally, Northern Goshawks during disputes over nest sites.
Peregrine Falcons have also been observed attacking Great Horned Owls.
Fun and Interesting Facts:
The Great Horned owl is also referred to as a cat owl, hoot owl, big-eared owl and “the tiger of the sky” because of its aggressive nature and ability to capture prey much larger than the owl itself.
A groups of owls are called many things such as "a bazaar of owls", "a glaring of owls", "a parliament of owls", or a "wisdom of owls."
Owls are considered symbols of wisdom and good luck in some cultures, but in others, they are feared as a sign of impending death and doom.
If a Great Horned owl was the same size as a human, its eyes would be as big as oranges.
The color of these birds varies with the area in which they are found.
Canadian and Pacific Northwest Great Horned owls are very dark, while the birds found in arid regions are usually very sandy in color.
Great Horned owls of the Arctic are practically white. This color trend in coats and plumage is typical in many species.
Great Horned owls occupy a greater variety of habitats than any other North American owl.
From forests, deserts and swamps to prairies, farmland and cityscapes, these owls are happy any where there is open land to hunt and trees to perch upon.
Great Horned owls take life-long mates.
Owl pellets are the undigested fur, feathers, bills, claws, teeth, skulls and bones of their last meals. It forms about 6 - 10 hours after the owl has eaten, and is then regurgitated up to six hours later.
This may seem gross, but this process does help keep the owl healthy.
Speaking of meals, the Great Horned owl is the only animals that eat skunks. Yum!
They will also feast on other birds of prey including owls.
In fact, these owls are the Barn owl's natural enemy.
Young Ospreys and Peregrine Falcons also fall prey to the Great Horned.
Flocks of American crows are known to harass the Great Horned owl, pestering it for hours or until the owl leaves.
The crow's hostility is well-earned as the owl is a major predator to their nestlings and adults.
Other small bird species, such as swallows, are also known for this behavior.
The call of the Great Horned owl is a classic sound of the wild and can be heard from miles away.
The sounds made by the owl vary with its mood and temperament. When calling for its mate, it makes a "who hoo, who hoo" sound. If aggravated, the owl will "clack" with its beak.
Young owls will "shriek" or scream for attention.
They inhabit nearly every type of terrain in North America from as low as sea level to as high as 11,000 feet.
They can live in deep forests, deserts, and in suburban neighborhoods and parks.
Well, it is time to fly for now.
Before I go, here is your positive thought for the week.
For beautiful eyes, look for the good in others; for beautiful lips, speak only words of kindness; and for poise, walk with the knowledge that you are never alone.
Never alone indeed.
We walk with the God of all creation.
He wants us to ask him, to be with him.
If you need wisdom -- if you want to know what God wants you to do -- ask him, and he will gladly tell you. He will not resent your asking.
Get all the advice and instruction you can, and be wise the rest of your life.
"Treat the earth well:
It was not given to you by your parents,
It was loaned to you by your children.
We do not inherit the Earth from our
Ancestors, we borrow it from our Children."
Ancient Indian Proverb
Your friend indeed,
Better yet, have them sign up so they can receive their own letters.
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