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

By on March 26, 2021 in BirdWords
White-breasted Nuthatch

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.

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The Lonesome Goose

By on March 3, 2021 in BirdWords
Canada Goose with Young

Canada Goose with Young

The number of Canada Geese inhabiting the Sacramento River area as well as ponds and lakes in the northern Sacramento Valley seems to be increasing every year.  The California Department of Fish and Wildlife affirms this with both aerial and ground counts of the species each year. Increased food supplies from grain and rice fields seem to surpass nutrients the geese can find farther south. Large lawns and golf courses are another attractant.

Canada Geese In Flight

Canada Geese In Flight

The consistent  “V-shaped” flying formations and lilting chatter  of the Canada Goose is familiar to most northern California residents. Some people call these waterfowl “HONKERS” due to these vocalizations. The large size and distinctive plumage of these geese with black heads and necks and a bold white cheek patch combined with gray brown bodies and white feathers under their tails make them easy to identify. Their wingspans range from 43 to 60 inches, varying among subspecies. Some researchers estimate 4 total Canada Goose subspecies while others estimate as many as 11, grouping the 4 smaller subspecies as a separate species, Cackling Geese.

The colorization of males and females is identical in all the groups. However, the male is larger and holds his body more upright, ready to defend his mate or offspring.

Canada Geese typically nest close to water, building their nest with large mounds of vegetation such as grass or reeds and lining it with down. The female usually lays 4 to 8 eggs before she begins to incubate them. It takes from 25 to 30 days before the eggs hatch. When one sees a pair of geese with 12 to 18 goslings it is usually because another female has parasitized their nest, adding her eggs to their own.

Canada Goose On Nest

Canada Goose On Nest

Goslings are precocial, which means they can swim, walk and feed as soon as they hatch. They are led to the water where they find grasses, tender herbs and even water insects the day after they hatch. Canada Geese are excellent parents. One adult swims in front and the other behind with a straight line of goslings between them. Both adults guard while the young feed, and when feeding is done, it’s the same routine: one parent in front and one behind with the offspring in a straight line between them. Ducklings only have the female to guard them and baby ducks tend to swim and feed helter-skelter, making them much more vulnerable to predators.  Female ducks often lose many of their little ones, while geese rarely lose even one gosling.

Canada Geese with Goslings

Canada geese form strong bonds within their family unit which includes the adult pair and all of the goslings, who seem to imprint on their parents as well as all their siblings. Groups of five to twelve flying in their “V” formations are likely to be a family group from the previous year. Young geese usually do not breed until they are 2 to 4 years old.

Mated pairs of Canada Geese can be together as long as 20 years but usually find new mates if one of them dies. Last year a devoted pair of geese nested and raised five goslings on the edge of the Sacramento River just below this reporter’s house. The male guarded them fiercely, so the family prospered and all five fledged. The original pair returned the following year, but unfortunately something happened to the female, so she couldn’t fly or swim. Eventually she disappeared, likely the victim of some predator.

Canada Goose Portrait

Canada Goose Portrait

The lonesome gander remained close to where she had been for about a week. He then joined a small flock of other geese and flew away with them. However, he returned after just 10 minutes. Another lone goose came and stayed with him for a few days and then they flew off but after about an hour he was back. This sort of thing happened repeatedly for several weeks. It was well over a month before he left for good.

Now we have a new pair of Canada Geese checking out the same nesting area. It may be our faithful lonesome goose returning with a new mate. Neither bird is banded, and they look identical. Guess we’ll never know, but we wish them luck and success.

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Spotted Sandpipers Dance to Their Own Tune

By 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!

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Home, Sweet Home: Bluebirds in the Neighbor-woods

By on December 26, 2020 in BirdWords
Western Bluebird Female

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 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

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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American Kestrels, Looking for a Good Home

By on November 21, 2020 in BirdWords
American Kestrel Male

American Kestrel Male

American kestrels are striking, with burnt-red backs and tails, steel-blue wings on the males, and bold falconid markings, black and white on the face. All this is packaged into a little hawk that could perch on your finger, and can inspire fascination in children and their attentive elders. And these rainbow dynamos are pretty to watch in action, too.

American Kestrel Female

American Kestrel Female

They will leap from a field-side post or overhead wire and flap forward until, spotting possible prey, they will fly in place, maybe twenty feet in the air, awaiting the chance to strike. Their prey may be a grasshopper or spider; or perhaps a vole. Vole trails are decked with their rodent urine, making pathways to dinner that kestrels see clearly with their UV vision.

Kestrels do not truly hover, as they cannot flip their wings over like hummingbirds in front of a flower, but they face into the wind and flap at an angle to hold their heads motionless, able then to discern the important motion below them. Their descent to that prey is not a peregrine dive but rather a wing-raised drop, ending, the bird hopes, in clutching a meal with its noodle-thin but wire-strong talons.

The kestrel may dine right there on the ground, or carry the meal to a higher perch. It may stash extra food in a handy clump of grass for later consumption. Or it may feed its hungry chicks.

Kestrels nest in cavities, where for a month the male brings food to the female while she incubates four or five eggs. Both parents then feed their nestlings for another month, when the young fledge. At that point, if food is abundant, the female may start a second clutch. The male will continue to feed both the fledglings and his mate.

Many songbirds are able to keep a relatively clean nest. Their young defecate in fairly dry packets that parent birds can lift and remove. Kestrel nestlings, alas, release a more liquid poop; but they do, at least, raise their tails and squirt against the cavity walls, keeping their nestling area as clean as possible.

Kestrels live year-round along open country across most of the US.  Some migrate, to nest as far north as Alaska and winter as far south as Panama. Older folks may remember them as the common “sparrow hawk” of farms and fields, but over the last fifty years American kestrel numbers have dropped by half as other Americans have paved and built on the fields, sprayed pesticides that have killed their prey, and cleared old cavity-bearing trees that provided nesting sites.

But Americans can offset these losses, too. To help counter the habitat change, you can put out nesting boxes for kestrels and other birds. Construction directions can be found at nestwatch.org; click “All About Birdhouses.” Do it now, and then see who comes along in the spring!

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