Archive | October, 2017

Avian Spooks Haunt the Night

Great Horned Owl

Great Horned Owl

Who-h’hoo-hoo-hoo! Not a Halloween ghost, but an owl. Some owls are smaller than robins, others bigger than your poodle, but they live all around us, locally and worldwide, almost invisibly.

Most common in North America is the Great Horned Owl. It’s not really horned—just feather-tufted—but these owls have the hearing, eyesight, feathering, talons, and instincts that make them formidable nighttime spooks .

Being nocturnal, the owls must keep warm. Their thick blanket of soft feathers does the job. Their feathering is so plush that a child’s finger poked into it can disappear. The Great Horned Owl is about the size of a housecat, but weighs only half as much, maybe four pounds. The rest is feathers.

The softness of these feathers helps insulate the birds, but it also promotes their silence. You may have heard the stiff flapping of, say, a raven winging by in daylight hours. But the owl’s feathers, soft and fringed at the wings, slip silently through the air, so that an unsuspecting rat is given no warning of its doom.

“No warning” is important. Daytime raptors—hawks and eagles—generally catch their quarry only 20% of the time. Snatching prey in the night can only be more difficult.

But owls are up to the task. They have huge eyes; imagine tennis balls on our human faces. Their pupils can open wide to catch dim shades in the dark. Their retinas are rich in rod cells, the photoreceptors that see only black and white, but still see when color receptors have shut down with dusk. Their huge eyes leave no room for their pupils to slide left-right as ours do, but they compensate with 14 vertebrae in their neck, twice our number, allowing their famous three-quarter head swivel.

Owl hearing is exceptional. Their cheek feathers form two little dishes that funnel sound into their ears, one on each side of the head, one high and one low. That high/low offset helps the owl pinpoint the source of a sound, much as a dog will by cocking its head. Tests on barn owls have shown their ability to capture prey in total darkness, by sound alone.

Once its prey is located, a hunting Great Horned Owl will loft from its perch and wing forward like a shadow. Its talons—not the typical three toes forward, 1 toe back of songbirds, but rather angled two forward/two back—will encircle its prey. Scarily strong—reported to be able to pop a steel-belted tire—the talons will pierce the lungs or heart.

Great Horned Owls are not picky eaters. They may hop on the ground to snatch scorpions and other invertebrates; they may eat frogs, mice, rats, or rabbits; coots, ducks, or other birds; squirrels, cats, or, thanks to an absent sense of smell, skunks.

Their nocturnal versatility—night, after all, happens all over—permits Great Horned Owls to live in forests, fields, wetlands, and deserts. They hoot to establish a territory and to coax a mate. In spite of her larger size, she hoots the alto and he hoots the bass. All dueted up, they will nest in trees, in stick nests or cavities, or in old barns, or on rock ledges, where they will deliver shreds of the local vermin to their hungry chicks.

And at this Halloween time of year, you may hear their hoots, but also the hisses, shrieks, barks, whistles, and wavering cries with which owls haunt the darkened skies.

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Plants for Birds

Cedar Waxwing

Cedar Waxwing on Toyon by Jay Thesken

After the long heat, the season for planting approaches. The local CNPS will hold its fall sale of native plants at the Shasta College Horticulture area on October 14, 8am-2pm. It may be an opportunity to dress up both your yard and the birds!

We only survive and flourish because of photosynthesis, the green-plant magic that turns solar energy into food energy. Without plants we would lack the wit to see a bird, as well as any birds to see. None would sing, or sprout a golden feather.

Praying Mantis

Praying Mantis

Fortunately, many plants survive our summer droughts and winter frosts. Trees, shrubs, forbs, and grasses provide a feast of seeds, nuts, berries, leaves, and nectar. Native plants support insects—caterpillars, leaf-hoppers, aphids, and more. Buckwheats, sages, coffeeberry, and toyon are among the many plants that support our pollinators—native bees, wasps, flies and beetles. The insects become food for so much of animate life, including our local fledglings who this month are fueling their first flights south.

Western Bluebirds

Western Bluebird Fledglings Waiting to be Fed

Many birds are strongly associated with oaks. Besides making nesting sites, oaks make acorns, which are devoured by jays, magpies, crows, ravens, turkeys, and band-tailed pigeons. Acorn woodpeckers store the acorns in rotting branches for winter dining. Lewis’s woodpeckers do the same, but meticulously shell and split the acorns first!

Acorn Woodpecker Granary

Acorn Woodpecker Granary

And oaks pass storms of insect energy on to hungry birds! Woodpeckers, titmice, and nuthatches dine on the beetles, ants, and spiders of the woody branches, and on the wasp larvae in oak galls. A stunning 534 species of butterflies and moths are known to lay their eggs in oaks, and those caterpillars feed orioles, warblers, vireos, mockingbirds, and bushtits. Bluebirds and flycatchers hawk the insects that take wing, and robins, sparrows, and towhees pick dinner from the detritus under the trees. Oaks are the crowning gem of many a lively yard!

Oak Titmouse with Insect

Oak Titmouse with Insect

Quail will roost in the oaks, but will gladly poke about at ground level in the thick protection of Ceanothus bushes, where foraging wrens and towhees may join them. Nearby lupines, after their bright show of blue flowers, will draw the quail out to dine on their nutritious seed pods.

California Quail Female with Chick

California Quail Female with Chick

The fruits from Coffeeberry, Toyon, and Elderberry attract robins, bluebirds, mockingbirds, waxwings, and nuthatches. Currants will also draw these berry-loving birds.

Goldfinches flock to sunflowers and thistles. Milkweed supports not just monarchs but eleven other species of butterflies and moths, too. Colorful grosbeaks dine on their seeds, and hooded orioles use the plant fibers to weave their nests.

Swallowtail On Western Vervain

Swallowtail On Western Vervain

Four species of hummingbirds are regularly seen in our area, and many flowers sustain them—woolly blue curls, larkspurs, penstemons, monkeyflower, fuschia, currants, and salvia. Some of these plants bloom through the winter, sustaining the resident Anna’s hummingbirds.

Anna's Hummingbird on Thistle

Anna’s Hummingbird on Thistle

For the adventurous, poison oak provides fruit and cover for quail, thrushes, sparrows, goldfinches, flickers, juncos, kinglets, sapsuckers, wrens, titmice, and a host of other songbirds. Don’t get carried away with toxic adventures, though. Nandina, known as heavenly bamboo, is a colorful but dangerous invasive that poisons birds with its cyanide-laced berries.

Gardening for birds is best done with a dose of indolence. Leave those dead-heads on the plant; they’ll feed the finches. Leave the leaves on the ground. Towhees and sparrows will breakfast on the bugs that turn them into mulch. Native plants are generally a great bet. Together with the birds they form a beautiful gift to yards all over. Enjoy!

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