Author Archive | Dan Greaney

Buntings: a tale of time, song, and brilliance

By Dan Greaney on June 2, 2021 in BirdWords

Lazuli Bunting Male

This season last year we had a torrent of reports of lazuli buntings scouring through the Whiskeytown brush and in the chaparral all around the North State. These little birds attract attention because they are visually stunning.

Western Bluebird Male

A superficial description of a male lazuli bunting makes it sound like a western bluebird: blue on the head and topside, pale belly, and a rusty-colored breast. But there’s no room for confusion in daylight viewing. The bluebird is darker, almost cobalt, its breast a burnt brick. The lazuli bunting, in contrast, looks like plugged-in high wattage gemstones–turquoise lapis up top, a moonstone belly, and red jasper on the breast. The bird doesn’t actually glow in the dark, but it has that look to it.

Lazuli Bunting Male

Each spring the females, with the same feather pattern as their mates but browner over all, follow up from Mexico a few days behind the males, who arrive first on the breeding grounds–Great Basin oases or brushy thickets throughout the West. The females will build their nests low to the ground, but first the males establish nesting territories by chasing and singing other males away.

Lazuli Bunting Female

Their music is vital. Buntings are like most songbirds in the way males stake out their breeding grounds by singing. But the song means so much more, too.

Yearling males arrive on breeding grounds with no song of their own. But like young people developing their place, they assimilate snippets from their older kith and kin, and piece those musical fragments into a pattern that becomes their own. In this way, they develop distinctive individual songs that share the phrasing of their community. The neighborhood recognizes and tolerates some encroachment from birds that share their song. Other buntings with unfamiliar music are vigorously chased off.

In evolutionary terms, buntings’ vocal cues serve to support perpetuation of a localized gene pool, a condition that can develop both distinctive beauties and destructive in-breeding. But change, for better and worse, is written into the laws of nature.

The tropics, so rich in the conditions for abundant life, churn out an amazing variety of species. It seems that buntings of yore expanded northward from South America, likely sometime well after our continents joined perhaps fifteen million years ago. But the birds became separated east and west when they hit the Great Plains, the vast grassland of North America that sported bison but not the brushy thickets where buntings make their homes. Divided, the western birds developed into what we call lazuli buntings, and the eastern group became indigo buntings.

Indigo Bunting Male By Kenneth Cole Schneider

More recently, however, the Plains have been breached; agriculture and other development introduced brushland where buntings from both east and west could live; and both could sing there, and hear each other’s songs. Apparently the young of both species readily adopt songs from either. They become musically bilingual, and then, as often happens when the same language is spoken, the two groups begin to court and nest together. Their young are proving to be fertile, so the hybridizing and rejoining of the two bunting species is ongoing in mid-America.

Whether that reunion will reach the west coast, and what new beauties it may produce, remains to be seen. Conditions change, and so then do nature’s children.

Lazuli Bunting Male

For now, though, we can enjoy the treat of our time. Lazuli buntings are striking compatriots. You might not recognize the nuances of their warbler-like trill as well as they do, but look for their blazing color in our North State brushlands!

Lawrence’s Goldfinch: Feathered Wealth

By Dan Greaney on April 24, 2021 in BirdWords

Male Lawrence’s Goldfinch

Gold comes in many forms–in nuggets, flakes, and veins. It also comes in birds.

One of the cutest little finches has got to be the Lawrence’s goldfinch. It’s gold is not the brilliant blaze of an American goldfinch, an almost neon beauty, but rather more subdued, with just wing and breast patches of yellow in its mostly-gray feathering. Not much longer than your longest finger, this little lemon freshet of song exuberantly trills, buzzes, chirps, and tweets wherever it is; and right now, it is here.

Core Lawrence’s goldfinch country is along coastal California for about 150 miles north and south of San Diego. In winter some will explore across the arid southwest as far east as El Paso. In spring some will flutter north as far as Redding.

Here they feast on the bounty of spring wildflower seeds, packed with proteins and solar energy locked in by the plants. A goldfinch favorite is fiddlenecks, whose golden blooms deck our oak savannah meadows. The lucky observer will see a goldfinch perched right on the flimsy flower stalk, riding it tipsily as she reaches into the flower cup for breakfast.

Fiddleneck

Wherever they roam, Lawrence’s goldfinches customarily travel in flocks and, like many finches, often wander nomadically. When settling down to nest, they invariably select a building site near a water source. Along a spring rivulet through a flowered meadow is perfect. There the flock begins to break up as nesting pairs form, although they often choose to nest in a sort of neighborhood.

Lawrence’s Goldfinch Female

Courtship includes perching close to each other, calling, and then beak-touching, wing-fluttering, singing, and feeding. Mated pairs continue much of their courting behavior. She builds a nest of soft plant parts, fur, and feathers, typically about ten feet above ground, and there lays her handful of eggs. She tends them assiduously, hiding them beneath her subdued coloring, keeping them close to her warmth, almost never leaving. Her little mate defends the area close around the nest, and brings her food, supporting her dedicated incubation. When she does leave the nest, he assumes incubation duties.

Lawrence’s Goldfinch Nest

Both parents gather insects to feed their helpless young, and then, if all goes well, reform their flocks to roam the meadows of their west-coast world. As home to these little finches, California is indeed the Golden State.

You’ve seen one, you’ve seen–well, one

By Dan Greaney on March 26, 2021 in BirdWords

White-breasted Nuthatch

Perhaps you have seen white-breasted nuthatches in your yard. They’re heart-warming little clowns, upside down more than right side up, with quizzical smiles in their dished-up bills, and funny little honking chirps, something like the beeping of a construction truck backing up.

Casually observed, they all look the same. But their variations in the US alone have been categorized into four subspecies that speak–or beep–in different languages. Other birds are similarly variable. Robins differ geographically and in depth of color; seven subspecies are recognized. Eleven types of crossbills are known–the crisscrossing of their bills variably suited to the different kinds of cones they crack for dinner, and their separate menus dividing them into different social groups and dialects.

Red Crossbills By Elaine R. Wilson, www.naturespicsonline.com

We’ve all heard about the loss of nature’s biodiversity, and perhaps how that loss strips ecosystems of the genetic flexibility to remain vibrant and productive in new circumstances–say, facing new chemicals, new climate, or new viruses. We generally understand the incalculable value of nature in enriching our lives, and now we have priced at some $180 trillion the commercial value of natural processes such as crop pollination, pest control, flood protection, greenhouse gas sequestration, medicine development, and air and water cleansing.

We have also noted some of the biodiversity declines over the last half century – 30% loss of North American birds, similar declines in insects globally, widespread fisheries collapses. It’s a grim picture.

But, we have argued, at least in the bird world, we really haven’t seen a flood of species extinctions. Nuthatches, for instance, are declining in our area, but they are increasing in the boreal forest–just moving north, as many species are. Unfortunately, the loss of biodiversity doesn’t happen with only species extinctions.

Nuthatches are like everybody else: unique. Their variety is not just as species or subspecies, but as individuals. Some are bolder, others more cautious. Almost certainly they have different disease resistances, risk awarenesses, and parental skills. So as bird numbers decline, they lose diversity within their species.

Probably we can more easily see the loss at the larger, subspecies level. Imagine if all horses were Arabians that might win the Triple Crown, but there were no draft horses to pull our grandparents’ ploughs. Imagine cattle with only Herefords and Angus, but not the Criollos that are replacing them as climates grow hotter and drier. Imagine the corn monoculture, almost destroyed by the blight of 1970, without the older, noncommercial variety to rescue it with blight resistance. Imagine people as only French, or Uyghur, or Hutu. In every species, the variation within it gives flexibility and resilience.

And beauty. I’m glad the nuthatches are doing well in the sub-arctic. But we can do better than just imagine them somewhere not here.

There are many drivers of the worldwide die-offs, and many of those drivers are interrelated. Climate change is one of the prime culprits. The sooner we wean ourselves from fossil fuels the less we will push the loss of both species and individuals. The more efficient we become with feeding ourselves without waste–in the field, out of the fridge, and through plant-rich diets–the more we will sustain the living world’s flexibility, resilience, and beauty. These are things we can do, both broadly in the world and locally. The material pay-off will not be instant, but it will be extensive and lasting.

Spotted Sandpipers Dance to Their Own Tune

By Dan Greaney on January 31, 2021 in BirdWords

Spotted Sandpiper

If you stroll along the river much this winter you’ll likely see a brown bird the size of a handspan doing the same thing. But you might notice that, unlike you, it is busy poking about the shoreline for insects and crustaceans, and its hind end bobs up and down almost incessantly. The bird may stop bobbing to fly skittering away from you, low over the water’s surface, showing white wing-stripes through its gray-brown topside. This bouncing bird is the spotted sandpiper.

Now don’t expect the spotted sandpiper to have spots this time of year. Spots are a dress-up item for the breeding season, dark dots boldly decking the bird’s white breast and belly, and their brown backsides, too. For now, though, they live their lives plainly–unadorned brown and white, always over or along water, and with just their tail-bobbing to provide some flair.

Spring, however, brings more than spots to these little shorebirds. They are one of the handful of species who break the breeding pattern common to birds and large fauna in general.

Most sandpipers breed in the Far North, where the twenty-four hour sun spurs explosive growth of plants and lichens, and the hordes of insects that feed on them. Those insects are food for millions of birds, and crucial to their efforts to feed their young. That environment is rich, but only briefly so. Winter encroaches at it from both ends. To nest there, sandpipers have evolved young who develop fast. They lay large eggs; the chicks emerge precocial, ready to run and feed themselves. To guide and protect their chicks through their brief, busy childhood, parents bond for at least a season, and sometimes for multiple seasons.

But spotted sandpipers, those bobbing birds along our riverbank, have spread their nesting grounds to include not just the Far North but rivers, mountain lakes and meadows, flats and shorelines throughout Canada and most of the US. They are the most widespread sandpiper on the continent. This gives them a longer nesting season than their Arctic cousins. But the females still lay those large precocial eggs, each egg 20% of its mother’s weight. They don’t produce more than four for a single nest; the physical toll seems to be too high.

Spotted Sandpiper Nest with Eggs

To take advantage of the longer warm season, perhaps the birds could raise two broods, as many songbirds do. But nature finds many ways to solve life’s puzzles. Spotted sandpipers maximize their reproduction by having the females focus on egg-laying and the males focus on child-rearing.

At breeding season, female spotted sandpipers establish breeding territories which they vigorously defend from other females and where they court up to four males with elaborate swooping displays and strutting. Over a 6-7 week breeding season, they lay an average of eight eggs but as many as twenty, with never more than four in a nest. The total number of eggs seems to be determined by the availability of food and males. For their part, the males separately tend and protect, even from one another, their individual nests and hatchlings.

Biological changes have evolved to support this reproductive process. At breeding season, females undergo a sevenfold increase in their testosterone, promoting their active courting and territory defense. Males produce high levels of prolactin, a hormone that promotes parental care-giving.

While nature has pioneered this reproductive technique, nature does not guarantee the success of any particular strategy. Like many species, spotted sandpipers, despite being widespread, have declined over 50% in the last fifty years. What comes next for them remains unknown.

Another unknown is the function of sandpiper tail-bobbing. Guesses range from the mildly plausible – say, aiding in balancing on rough terrain – to the absurd – say, pumping body oils over their feathers to improve waterproofing. That latter reckoning is imaginative, but completely lacks physiological evidence. Since convincing explanations still elude us, the hypothesizing is wide open. Have at it!

Home, Sweet Home: Bluebirds in the Neighbor-woods

By Dan Greaney on December 26, 2020 in BirdWords

Western Bluebird Female

There’s a little piece of sky fluttering through the neighborhoods and neighbor-woods of the North State. Actually, many little pieces. But they are not at all Chicken Little’s nightmare; the sky isn’t falling. They are, rather, feathered beauties, and, if one is to believe the folklore, bringers of happiness.

Western Bluebird Male

Western bluebirds thrive from Mexico up through the coastal states in just about any habitat that provides a mix of open woods and small meadows – say, for instance, the neighborhood woodlands of our area. Here the birds find everything they need to prosper.

Oak trees offer low branches, perfect perches from which to scan the weeds beneath, to drop down and snatch a tasty caterpillar or beetle that shows itself. That swoop-down style of hunting, for reasons that might be discernible, is known as hawking.

Oaks also seem to die for nearly as long as they live. Old oaks are notorious for holding dead limbs, and that rotting wood, with help from the squadrons of local woodpeckers, can contain entire housing developments–cavities–that bluebirds, along with others, will make their homes.

Male Western Bluebird Feeding Nestling

Within the oak woodland numerous berries are usually available to help balance a bluebird’s insect diet. Elderberries, toyon, grapes, and poison oak are high-calorie menu items, perfect for powering through the cold winter days and nights. Mistletoe berries–toxic to people but nutritious to birds–are a special favorite. Bluebirds will often defend a rich clump of mistletoe from phainopeplas or other birds that might want to claim that aisle in their grocery store; they will perch above the mistletoe and chase invaders off to their own fortunes. No reports on what the bluebirds do under the mistletoe.

There are other birds that are blue in our woodlands, but don’t mistake scrub-jays for the real bluebirds. Both may flock loosely with a half dozen kin, but the jays are long-tailed and raucous. The bluebirds are more demure. They are thrushes, relatives of robins, but with a quieter song, a chirp with a spring in it, seemingly just to keep the friends together.

With the sun behind you, males’ topsides almost sparkle with rich indigo-blue. Their breasts are decked in rusty red. The females are similar, but much paler throughout.

Western Bluebird Eggs

Together they house-hunt in spring, as many species do. Then she will build her nest, taking two weeks for the first nest of the season but, perhaps with a fatigue-induced shift in priorities, only one week for the second. In each she will lay a handful of eggs, most but not all of which are apt to be sired by the male attending her. She will incubate them for two weeks, and both parents will tend them through their fledging, another three weeks or more.

Western Bluebird Fledglings

Even with extensive habitat changes, bluebirds seem to be holding their own. The cutting of dead limbs that could provide nesting sites has been offset by providing nesting boxes. Complementing numerous backyard bird-houses, our local Wintu Audubon has developed “Bluebird Trails,” strings of boxes used by bluebirds, tree swallows, nuthatches, and others. The Audubon chapter monitors those nestboxes and tracks the results for researchers. Last year the local Trails fledged 139 young birds.

Monitoring those nests is a fun weekly activity through the spring season. And yes, it is appropriate for doing with a child. If you would like to learn more about volunteering as a Nestbox Monitor, contact webmaster@wintuaudubon.org .

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