Author Archive | Dan Greaney

…because they don’t know the words?

By Dan Greaney on May 25, 2019 in BirdWords

Anna’s Hummingbird Female Feeding from Peruvian Lily

When Columbus arrived in the Americas thinking he’d found a new route to India, he marveled at another new discovery, too. He wrote in his diary of little flying gems, the ones that we call hummingbirds. Of course, the locals had loved hummingbirds long before Columbus. Aztec kings wore whole cloaks made of their shimmering skins. In what became New England, Native Americans wore hummingbird earrings. After Columbus, the pope and then fashionistas throughout Europe soon included hummingbird skins in their décor.

Rufous Hummingbird Male

The fascination is understandable. Smaller than any other bird, more brilliant, and, for those who saw them alive, capable of flying in one place, these creatures were magical! But they are even stranger than the rapt observers of old could appreciate.

Anna’s Hummingbird Male

Being so small, and warm-blooded, requires a high metabolism. Variably among their three hundred plus species, hummingbirds live at 10 heartbeats and two breaths per second, conditions that would kill a human. At such high rates, they burn their energy fast, and can begin to starve in as little as fifteen minutes. To survive through the night, some species routinely go into torpor, a sort of mini-hibernation, to internal temperatures as low as 48 degrees, slowing their body processes and conserving energy until the next day of frenetic feeding.

The feeding itself includes catching small insects from the air—they do need protein, after all—and famously, drinking the high-energy nectar of flowers. Plants, of course, benefit from hummingbird visits because, just like bees, the hummingbirds pick up pollen and spread it about, fertilizing other flowers. These bird-loving, or “ornithophilous,” flowers often co-evolve with certain hummingbird species, matching, say, curved bills with curved corollas, to maximize nectar-gathering and pollination for just those birds and flowers.

Green Hermit Female, Costa Rica, photo courtesy Michael M. Baird

To be able to gather nectar, hummingbirds have a unique hovering capacity. Most birds flap their wings up and down and the physics of the Bernoulli principle keeps them afloat as they go forward. But to hover, hummingbirds have an extra capacity. After their down and forward wingbeat, they can flip their wings over to arc down and backward, creating a figure-eight motion that holds them in place. Of course, all of this happens at some seventy wingbeats per second, so it wasn’t discovered until high speed filming allowed researchers to slow the blur to a visible level.

Hummingbird coloring includes pigments like that of most living things. But with a rare level of expertise, their feathers also create color with refraction. Sunlight bouncing off the birds is bent by minuscule feather cells that act like prisms. Depending on the species, male hummingbirds’ throat feathers, called a gorget, shine with particularly iridescent brilliance. No fools, males orient themselves opposite the sun to flash most brightly to females they are courting.

Calliope Hummingbird Male

The old joke—that hummingbirds hum because they don’t know the words—really isn’t right. They do know the words—and their languages are as bizarre as so many things about them. Many talk with their feathers, with particular feather-hums unique to different species. Many talk with flight patterns. A male Anna’s hummingbird, the only hummer species to stay in our area through winter, dances high into the air near a female he is courting, then dives down into a j-curve in front of her. In case that alone is not enough to impress his heart-throb, at the bottom of his dive he pops the air with his outer tail-feathers, creating a loud, staccato explosion that we unfeathered humans have trouble recognizing as sound from very small quills.

Alas, as far as we know, his ardor does not extend to caring for the young. The female builds her tiny nest of plant parts and spiderwebs, and tends her two eggs and hatchlings for over a month. Gardens with the tubular flowers that hummingbirds love can help her succeed in raising her little ones.

Anna’s Hummingbird Female on Nest

Chaparral Homes

By Dan Greaney on April 27, 2019 in BirdWords

Blue-gray Gnatcatcher photo courtesy David Bogener

We just might live in one of the world’s most under-appreciated plant communities. Although so many of us make our homes in the chaparral, people often look past this native brushland to sigh at the forests above us or the spreading fields below. They are missing a lively world right here.

Chaparral is a community of living creatures uniquely adapted to the Mediterranean climate at about our latitude on the west coasts of continents around the globe. It’s not desert because of winter rains. It’s not forest because of regular summer heat and drought. It’s not grassland because, historically, its fires were too infrequent.

How do the plants survive, here where we huddle indoors with AC? They minimize water loss. With leaves that are tiny or vertically oriented, they cut their exposure to the withering sun. With waxy surfaces or whitish colors they reflect sunlight. With thick, resinous leaves they resist wilting, and with hairy surfaces they catch water vapor that cools the plant as it re-evaporates.

The success of these plants creates a thick bramble, a perfect hideaway for numerous animals wherever it grows. The tale of Br’er Rabbit and his safe briar patch has origins that include the fynbos, the African version of what we call chaparral. Here in California many birds find the brush a safe and welcome home.

Wrentit

Wrentits are tightly tied to their shrubby habitat. The size of a tangerine with a long, cocked-up tail, these hideaway gray-brown birds weave their way through the brush picking insects and making up for their near invisibility with a common chaparral song, described as a bouncing ball accelerating and ending in a trill. Strictly local, wrentits mate for life shortly after fledging and stay their whole lives in the brush within a quarter mile of their native nest.

Black-chined Sparrow photo courtesy David Bogener

Black-chinned sparrows also hug the scrub, but they vacation in Mexico each winter after the work of raising their kids here. These pink-billed beauties are reclusive, rarely seen even by avid birdwatchers except when a spring male perches on a low shrub to sing his heart out. They seem particularly rain-sensitive. Too much or too little precipitation reduces their nesting success.

California Thrasher photo courtesy David Bogener

California thrashers are another timid-seeming bird of the chaparral. They like to remain under brush when they scrape for insects, and their long, curved bills allow them to keep an eye up and out for predators even while foraging. They will, however, perch high and exposed in the tallest shrub around to sing loud and long for a mate! Some things seem even more important than safety!

Blue-gray gnatcatchers break the mold of “secretive” chaparral birds. These plucky little balls of fire energetically twitch their tails sideways and chase scrub-jays at least ten times their size. As a species, they range broadly, nesting in scrublands and forests across the US, and annually migrating as far south as Central America. Their habit of sprinkling other birds’ songs into their own buzzy trills has earned them the title “Little Mockingbird.”

The chaparral where these birds prosper is often misunderstood regarding fire. While many chaparral plants do bounce back from burns, either by crown sprouting or with seed germination, they cannot endure frequent fires. Their historic burn rate seems to have been on the order of 30-150 years. More frequent burns kill off the chaparral and turn it into grassland.

That has been happening recently. The longer, hotter summers of our time have joined with development to diminish chaparral for both people and birds. The Carr fire alone burned over a thousand homes and over 200,000 acres of habitat. In the last fifty years, wrentits and California thrashers have declined by a third, and black-chinned sparrows by a catastrophic 72%.

Fortunately, however, we can live here and still have a “here.” With thoughtful siting, landscaping, and construction material choices, and by steering away from fuels that create the longer, hotter seasons of our fires, we can continue the rhythms of the chaparral and coexist with the wild beauties that also make it home.

Good Things Come in Small Flocks

By Dan Greaney on March 30, 2019 in BirdWords

Bushtit Male photo by David Bogener

In the list of things cute, bushtits belong right up there with babies and buttons. They’re tiny and fluffy, sociable, soft-voiced, and soft-toned. They’re the downy little twittering things, the size of a mouse, the weight of a hummingbird, and the color of a country road. They fly severally from one tree to another—three of them together, then four more, oh, ten of them, and another seven, and sometimes on up to several dozen. They gently tweet among themselves—“I’m here,” “I’m here,” “I’m right here with you”—keeping loosely together as they scour leaves and twigs from every angle to find their miniscule insect meals.

Bushtit Male

Up close, their gray-brown feathers seem softer than an Easter chick’s. The males look gentle, doe-eyed. The females sport a modest adornment. Their eyes are amber.

Bushtit Female

But the great extravagance in the bushtit world is their nest. Both parents and sometimes additional helpers, too, work for up to a month to weave their hanging crèche. It might be in weeds just off the ground, or it might be a hundred feet up in a tree. It is often at a handy viewing level. Imagine a hanging tube sock, a foot long, woven of soft plant fibers meshed with strong spider webs. In that mossy pouch the young will hatch and grow. The upper part of the sock, stitched closed against its supporting leaves and branchlets, holds a single half-inch peep-hole, the nest’s only doorway.

Bushtit Nest

The extensive work required for their elaborate homes seems to structure much of bushtit life, but they face the challenge with a pragmatism that would make a yankee proud. First, they do not migrate. Staying put allows them to start building their homes early, as early as mid-winter, when mild spells begin to break winter’s chill. Second, mated pairs stay together for several years, a level of commitment normally seen only in large birds like swans and eagles. Their mating fidelity spares bushtits from hitting the dating scene every year, and leaves more time and energy for nesting. Third, once they build a nest, a pair will usually reuse it for a second clutch of eggs. Building a new architectural masterpiece would take time and energy away from that second batch of young.

Bushtit Female Emerging From Nest

Fourth—ah, being tiny does not make life less complicated. Bushtits live in flocks of about 10-40 birds. They travel together when foraging, they huddle together when it is cold; they sometimes intersect with other flocks, but then reform their own. And in nesting season, when there are unmated birds or when flock-mates lose a nest, they often undertake what is called plural cooperative breeding.

Adults without their own nest will often help their flock-mates at all stages of nesting—construction, incubating, feeding young, and shepherding fledglings. Up to six adults may help at some nests, all sharing in the warmth of the home. Helpers often continue to feed fledglings while the breeding pair starts a second clutch. Sometimes two or more females will lay their eggs in the cooperative nest. The DNA studies to determine paternity in shared nests have not been done.

Close views are often possible with little birds. When my daughter was a child a flock approached us in the back yard, twittering through twigs just a yard away with their peeping and soft feathers. We watched, and she scrunched her nose over a smile as if in recognition that Oh, there’s beauty in the world. It’s a view I’d wish for every child, and every parent, too.

Floating Dinosaur Birds

By Dan Greaney on February 23, 2019 in BirdWords

American White Pelican

What California bird weighs five pounds more than our ten-pound eagles, has a wingspan two feet longer than the eagles’ seven feet, and a beak twice as long as a great blue heron’s? What bird is rumored to eat its own young, and also to feed its young with its own blood? What bird is noted in a 1910 poem by Dixon Lanier Merritt as wonderful because “His bill will hold more than his belican”?

Yes, the bird is the American White Pelican. (And yes, the poem is by Dixon Merritt, not Ogden Nash.)

These old birds, with fossil relatives going back half way to the dinosaurs, are shy of people, and remain an infrequent sight in Shasta County. But they are here. They nest along the shallow lakes of north-eastern California, and they winter even closer, throughout the Sacramento River Delta. Occasionally we spot them.

American White Pelican Group In Flight

On a quiet summer day they might float high overhead. They typically proceed in a silent group of fifteen or so, with not a single one of them deigning to speak or flap a wing. Their long bills spear forward like a pteradactyl’s; their motionless, extended wings show black flight feathers on otherwise snowy plumage. They hang in the summer-blue sky, still as pallbearers, seeming beyond the rule of something as mundane as gravity.

But of course they are fellow Earthlings, and sometimes will tilt Earthward and glide severally into a water-ski landing on a shallow lake. They prefer shallow lakes because of their feeding style.

Brown Pelican Dive

Their coastal cousins, the brown pelicans, plunge into the water and scoop a beak-full of ocean and, they hope, stunned fish. White pelicans, on the other hand, paddle along the surface to find their food. Frequently they group together to swim-herd fish into shallow coves, where they can more easily scoop a mouthful of prey, either from their normal floating position or by tipping tail-up like a mallard. White pelicans will swallow salamanders and crawdads, but they mostly dine on warm-water fish like carp and minnows.

Each spring, the adults’ beaks brighten from yellow to orange, and they develop a rounded ornamental fin on their upper bills—an accessory that perhaps one must be a pelican to admire. The mated pair scrapes out a hollow in sand or gravel where the female lays 2-3 eggs. Only one of the young will usually fledge. Their in-nest competition is fierce.

While incubating or otherwise resting, pelicans often tuck their bills down their front sides. It may be this habit and the red-orange bill of the breeding season that fostered the mistaken myth that adult pelicans feed the young their blood. They do not.

American White Pelican Resting

As for the grisly tale that parent pelicans eat their offspring: adult pelicans do not carry food to their young in their pouched beaks. They swallow the food and then regurgitate it for the nestling. On its part, the baby stimulates regurgitation by sticking its own beak down its parent’s throat. The scene looks very much like the parent is eating its baby, head first. The feeding practice and the tale it inspired are primitive and perhaps galling; but the unpretentious dining style seems to have worked for 30 million years.

White pelicans declined for the first half of last century, perhaps in part due to the loss of a major nesting rookery when the progenitors of the Westlands Water District drained Tulare Lake, which at the time was the largest lake surface west of the Mississippi. But now the pelicans are recuperating—into new trouble, expanding into the southeast where catfish farms create rich feeding grounds.

Homes for Birds, Yard by Yard

By Dan Greaney on January 26, 2019 in BirdWords, Conservation

Hermit Thrush

For birds, yard after yard after yard adds up to a lot of potential homes. Backyard sanctuaries are pleasant for people, too, and fairly easy to provide. Just consider the basic elements of habitat: food, water, and shelter.

Providing food does not require filling feeders. Feeders can be fun because they draw birds for easy viewing, but they also require periodic cleaning to minimize spreading disease—say, once a month with a nine to one water to bleach solution. Hummingbird feeders require cleaning and refreshing every 2-3 days in the summer.

Plants will feed birds with less fuss. Berries and seeds on shrubs, grasses, and trees are all natural food supplies. Flowers, especially tubular ones like fuchsia and penstemon, offer nectar to hummingbirds. Benign neglect of gardens leaves old seedheads for winter consumption and unraked leaves for scratching through for the food they hold. Even without bird-edible fruits and seeds, plants feed insects, which become the main source of protein for songbirds around the world. Native plants are usually best, as they have evolved with the birds and insects of the area and usually support them most effectively.

Cedar Waxwing and American Robin

Of course, avoid pesticides and herbicides. At worst they poison the birds, and at best they kill off the birds’ food source.

Plants also offer shelter. Some birds roost high in trees, others in shrubs, still others on the ground under brush. If décor and fire safety call for pruning up, consider retaining some low shrubbery for sparrows or quail. Woodpeckers carve numerous holes in dead wood, creating homes used by many bird species. You may choose not to leave whole snags standing, but just a standing trunk can invite excavations that bluebirds, wrens, flycatchers, titmice, nuthatches, and swallows will readily use.

Western Bluebird Male

Those familiar cavity-nesters will also use home-made nesting boxes. To find bird-house directions, at wintuaudubon.org see Places to bird/Attracting birds. In our area, it’s best to mount your birdhouses in shaded areas.

Ash-Throated Flycatcher

Of course, ensure that your yard is as feline-free as possible. Outdoor cats kill 15-20% of North American birds every year, including nearly 50% of suburban fledglings.

Water remains the elixir of life. A shallow pan, refreshed every day, makes an easy start. A trickle of running water invites many more visits. Small pumps are inexpensive and can run a home-made fountain if electricity is safely available. For permanent pools, mosquito-fish are available from Shasta County at (530) 365-3768.

Consider commercial fountains carefully. Songbirds prefer shallow puddles; a sloping edge will accommodate birds of different sizes for both drinking and bathing. Steep edges inhibit use.

Ruby-crowned Kinglet

Birds have lost vast swathes of former habitat. The wildfires are hardly the worst of it. If we can curb the super-sizing of them, fires are natural, and the cycle of light burn and fresh regrowth benefits many species. The more devastating disruption is the permanent and widespread habitat conversion of historical oak woodlands, wildflower fields, and riparian meanders into row crops, monoculture orchards and tree farms, pavement, and buildings. Now climate change is expected to further eliminate half the seasonal range of 314 North American bird species. It’s a tough time to be dependent on an ecosystem.

We can shape our yards to offer the food, water, and shelter that will help many birds still find homes.