The great spring weather has miraculously continued through another full week of late March. In fact, March has been so unusually mild, I am beginning to worry about what April and May will bring.
I tend to believe that since our annual amount of precipitation varies little from year to year, remaining at about 14 inches, that if we don’t get the usual amount in March, we will more than likely get it some other time. Will it be another 4-foot snow like we had a few years ago in May or will it be just a series of smaller snows in April? Is this a result of climate change? Will warmer weather continue into our future? If so, it can have catastrophic effects on wildlife.
No matter what comes, no one can deny that this March weather has been delightful. At least for this year, we have had fine spring weather. This has triggered many changes, especially down below us on the plains. Trees have already leafed out at Chatfield and Bear Creek Lake Park. Alfilaria and Easter daisies are in bloom as well as many garden plants such as grape hyachinths, daffodils and crocuses.
Early star-drift (Pushkinia) is in bloom here in my garden. We can still have cold weather in Denver, and many of these early plants may be nipped by frost. Canada geese and other waterfowl are beginning to return to lakes and ponds on the plains.
I went to Bear Creek Lake Park last Friday with friends, who wanted to see the nesting great-horned owls, which had been reported there.
The great-horned owl is the largest of the tufted-eared owls. Only the snowy and great gray owls are larger, and they both have smooth, rounded heads. The great-horned owls, like all owls, cannot move their eyes. Therefore, they have very agile necks, so they can swivel their heads from side to side very quickly and silently.
They usually have a favorite perch where they appear and sit more evenings just before dark. They catch most of their prey by sitting on such a lookout and swooping down on anything that moves or squeaks, then moving back to the perch to eat. Beneath such a perch is a good place to look for discarded bones or the regurgitated pellets they make if you want to study what they have been eating.
Great-horned owns are found all across the United States and from timberline south through Central and South America to the Magellan Straits. They will nest in tree cavities but today there are few old trees that have cavities big enough for them to enter. Lacking a big cavity, they will build a nest in the tops of trees, often using an old hawk or crow nest as a base and adding to it. They will. if forced to. use an old magpie’s nest as a base, but as a rule, these are lower. and the owls are unhappy being down where they are vulnerable to predators.
There are many forms or subspecies of great-horned owls across their huge range, and they vary a good bit in color. The far-north owls are often almost all gray with very little coloring even in their facial discs. The eastern great-horned owl is very colorful with rust to orange-ish facial discs and is more brownish than gray.
The southwestern form varies from somewhat rusty facial discs to decidedly gray. The Pacific coast birds are dark gray. All of these forms have colors merging from nearby populations. The female, as is other owls, is bigger and browner than the males.
Our great-horned owl locally is usually grayish with less orange in its facial discs. There are many colloquial names for the great-horned owl. They are known as hoot owls, cat owls, king owls, tiger owls, etc. All relate to their size, shape and ferociousness.
They hunt to feed themselves and their young. For many years, we had a pair of great-horned owls nesting on one of the high shelf ledges of Kinney’s Peak behind our house. Then a mountain lion moved into a cave nearby and had three young. This was apparently more than the owls could cope with, and they moved out and have not returned.
When it was in residence, it started calling in late December and continued until it was mated. My husband Bill used to answer his call, but one night it came in closer and apparently discovered that Bill was not a female owl for it flew off and never came to his call again, although it continued to call from the peak.
Great-horned owls are vicious hunters with very powerful talons and strong sharp beaks, so the much larger female is a real threat to the courting male. He keeps his distance until she shows signs of accepting him and that she is not hungry for she could just as easily decide to eat him as to mate with him.
Once mated, the male helps incubate the eggs and then helps supply the large amount of food it takes to feed themselves and the young. They lay as many as three to six eggs, but the normal brood is usually one to three. When nearly grown, but still unable to fly, they often leave the nest, and the adults continue to feed them on the ground.
At this stage, the adults try to teach the young to catch their own food. The adults fly over and drop food, trying to teach them how to catch their own. The young often become pretty hungry before they learn, and they fly after the adults, crying and begging to be fed. They sound like someone being murdered, and I often get calls about them at that time. Once they learn to catch their own food, things quiet down, and usually the family breaks up into single birds over winter.
If you have any concerns about a great-horned owl, don’t try to do anything for it yourself. Call the Colorado Division of Wildlife for these birds are strong fighters, and when they think you are trying to hurt them, they are vicious.
Bill and I were called one day years ago about one that was caught in a muskrat trap on Upper Bear Creek. The trap had a chain on it, and this was caught in a barbed-wire fence. The bird was hanging upside down and seemed exhausted, bit was all we could do to get it under control and free of the fence. Then we had to hold it still to get the trap off its food. It did not appreciate our effort and never gave up trying to sink its talons into us.
We checked its injured foot, and it didn’t appear to be infected, so we released the bird and wished him well. He flew off without so much as a thank you.
They are big interesting birds, fascinating to watch and listen to, but don’t try to handle one. Bill and I had had some training at a museum in Buffalo, N.Y., or we would never have succeeded and even then it took two of us to hold and handle the bird.
Another word of warning: Great-horned owls can’t tell your pet cat from any other animal while out hunting at night, so if you love your cat, keep it inside. Between loose dogs, coyotes and great-horned owls, domesticated cats don’t stand a chance if they are out all night in the wild. Keep them inside.