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Eared Grebes Tone Things Down for Winter

By on February 28, 2022 in BirdWords

There is, apparently, a lot to be said for having a time of rest: trees drop their leaves and go dormant; fungi retreat underground; insects wrap in cocoons, and chipmunks hibernate; lizards and turtles brumate – the reptilian version of hibernating; we humans developed a Sabbath, and weekends.

Birds, however, are largely committed to being lightweight and active. Hibernation and weekends are not options for them. Some smaller birds and nightjars can lower their metabolism to sleep through a cold night or even longer harsh conditions, but mostly birds survive tough weather by either migrating away or foraging voraciously.

Eared grebes, however, have found another way to amplify the benefits of rest.

Out on our lakes and rivers, they are in their resting mode right now. As many birds do, they have toned down their social demands, dropping their extravagant yellow plumes of breeding plumage–their “ears”–and the showy dances that go with them. They wear plain black and white now. They are not singing, and scarcely even talking, spending their time in loose solitude. Most stunningly, they cannot even fly.

For 9-10 months of the year, eared grebes don’t need to take wing. They need to feed–for themselves in winter, for their young in the spring. So they give up flying for extended periods of the year. Their flight muscles shrink, and their digestive organs grow. They eat and they rest. The invertebrates of open water in places like Turtle Bay and along Park Marina become their meals and muscle. The water itself is their home and refuge. The birds don’t hibernate, but they eat and store their calories with high efficiency.

Spring will call soon. Then the eared grebes’ pectoral flight muscles will grow, and the winter’s rest and food storage will power their flights. First they will wing their way to either Mono Lake on the east side of the Sierras or the Great Salt Lake in Utah. Those two lakes act as a staging ground for 99% of all the eared grebes in North America. They are rich in brine shrimp, and the grebes feed voluminously. The more shrimp they swallow, the greater their reproductive success.

Well fed, the grebe flight muscles again develop and they fan northward to nest in freshwater and saline lakes from northern California up through central Alberta and Saskatchewan. There they will court with elaborate dances on the water.

Well built for swimming, with their feet located back toward their tails, grebes are awkward, essentially crippled, on land. Following their successful aquatic-dance courtships, they will build floating nests in cattails or similar vegetation. Depending in part on the density of brine shrimp in their staging ground lake, the grebes will raise one to eight chicks.

The chicks are quickly active, diving and hiding just an hour after hatching. But they are also not above taking warm rides on their parents’ backs. Eared grebe parents will join with neighboring nesters to share their parental duties.

As summer progresses the young will be increasingly on their own. By September they will have developed the strength to fly to one of the great saline lakes of the American west, where they can continue the cycle of losing their flight muscles, and feeding and resting.

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Great Egrets don’t make sense – sort of

By on January 29, 2022 in BirdWords

Great Egret with Cattle Egrets

Camouflage clearly makes survival sense. But Nature doesn’t settle for just one kind of sense. Out along river shorelines and on the damp fields of winter, great egrets are blatantly visible, as uncamouflaged as possible in head-to-tail white.

They’re large. They’re out in the open. They’re plainly visible. Shouldn’t they be dead?

Great Egret Reflection

A hundred years ago they almost were dead. Ninety-five percent of great egrets in North America were wiped out, and it was indeed because of their feathers. The fashion of the day was to decorate lady’s hats with their fancy plumes, and so the birds were slaughtered and plucked. The plumes are especially showy in breeding season, so the birds were often taken while they had chicks in the nest; the young of course subsequently starved. This avian massacre sparked the founding of the Audubon Society, whose emblem became the great egret. Those Audubon activists moved a responsive Congress to pass the Migratory Bird Act in 1913, and egrets and other feather-hunted birds quickly recovered.

An interesting side note on John James Audubon, who died half a century before the organization took his name in honor of his famed bird paintings: he was blind to birds’ conservation needs. According to Smithsonian Magazine “Audubon insisted that birds were so plentiful in North America that no depredation—whether hunting, the encroachment of cities and farmlands, or any other act of man—could extinguish a species.” Recent trends, of course, have shown him exceedingly wrong.

Nonetheless, although other birds are in decline, great egrets are flourishing. They are versatile, readily foraging in the shallows of marshes, riversides, or coastal shores for fish, or reptiles, amphibians, crustaceans, or insects; or hunting in the deeper water of protected bays by standing, toes spread, on floating kelp. Or they will move into fields and spear gophers or voles with their dagger-like bills. Their foraging flexibility allows them to shift from less productive habitats into livelier ones.

Great Egret

Great Egret Fishing

Beyond their feeding versatility, great egrets nest with flexibility, too. They nest in colonies with other egrets or herons; but they can nest alone, too.

The male starts to build a platform of sticks, high in a tree; or, as availability requires, at the top of a bush, or even on the ground.

He courts a female with displays of his fancy plumes and his long beak, which turns green at its base, and with tumbling flights and offerings of twigs. She, also dressed to impress, may return his displays and then help complete the nest. Together they incubate and feed a few chicks. Birds are not universal practitioners of civilization, however, and if food is tight, larger chicks may stab and kill their younger siblings. It takes a while for young egrets to develop the cooperation and tolerance their parents exercise.

Great Egrets Nesting By Larry Goodwin

Great Egrets Nesting By Larry Goodwin

There are always things we don’t know. Great egrets are large, and large birds often mate for life. But egrets also carry out extensive courtship, which can suggest the wooing of a new mate. Or, again, perhaps egrets are among those fine creatures who sustain courtship throughout their relationship. We just don’t know.
But we know that they survive and prosper without a bit of camouflage. It’s a beautiful thing that Nature supports more than what at first glance seems rudimentary.

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Golden-crowned Kinglet – A good thing in a little package

By on December 25, 2021 in BirdWords, Uncategorized

Golden-crowned Kinglet photo by David Bogener

When the nights are long and frost can be expected, most insects forsake activity and hunker down as eggs or pupae, waiting for spring to resume their active lives. Insect-eating birds feel the rhythm of the season and their sleeping food source, and head south. But some stay, making their winter-living by searching hungrily, maybe frantically, for those sleeping insects.

One such bird is the golden-crowned kinglet. It’s a “king” because it wears a crown – golden in the female and brightening to orange – gold in the male. It’s a kinglet because it’s tiny. At a fifth of an ounce, the golden-crowned kinglet is scarcely larger than a hummingbird. But when hummingbirds head south, vacating the eastern US and leaving just one of their kind to face the milder climes of California, the kinglets stay closer to their nesting grounds. They remain as far north as southern Canada, where they can face temperatures down to -40 degrees.  It seems they should shiver, starve, and die, but they do not. Instead they hustle in small flocks, usually high in winter’s trees, scouring twigs and conifer needles for the precious calories in moth cocoons and tucked-up spiders.

Golden-crowned Kinglet by Rhododendrites – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=95715477

Still, they must not waste at night those calories found throughout the day. Like other social animals, a single kinglet in such cold would likely freeze. Instead, they huddle together in protected cavities, bunched close, sharing body warmth. They fluff their small downy feathers, slowing their loss of heat. They survive.

Our area, of course, is not quite so frigid–although plenty cold enough to kill a lost hiker or solo pip. Many of our local golden-crowned kinglets seasonally drop down from the mountains where they raise their offspring. Some winters they can be seen in good numbers along the Sacramento River. An acute ear might hear their brief high trill as they keep in touch with their fellows in the highest foliage.

A studied glance upward might reveal them flitting about in the canopy. However, without binoculars and some practice using them, golden-crowned kinglets are likely to remain barely discernible silhouettes. But if the bird and the viewer contrive to enable a good look, then the viewer will have eyed one of nature’s sweeter gems.

They’re like a sunrise behind hills: pale gray below, then above mixing yellows and darks. Their bright crown is offset with a trim of black; when the male is excited the copper-alloy gold of his crown is raised and especially prominent. The whole of their feathering seems to include both gentility and radiance.

All packaged small. It does take some time and intent to see a golden-crowned kinglet, but the experience is worth it.

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Turtle Bay Provides Natural Wealth

By on December 5, 2021 in BirdWords

It is the Thanksgiving season, and Redding has a special treat to appreciate. We have naturally what many cities spend a lot of money striving for: a place like Turtle Bay.

Sundial Bridge

On any temperate morning, and many others too, the Bird Sanctuary Loop is the hub for a stream of cyclists, dog-walkers, joggers, retired couples, friends, young families, and bird-watchers. Children gaze at green-headed mallards and study the giant webs of garden spiders.  Parents guide their children to the trailside as bell-ringing cyclists approach. Walkers watch jacketed fishermen float below them, their boats drifting, their lines in the water. In fall, when the weather is right, the trails and visitors can be showered with golden leaves.

Mallard Pair

Mallard Pair

This welcoming and well-traveled route lies in the heart of Redding, nestled inside a bend in the river that creates the maze of bywaters and peninsulas that, together with the main river channel, comprise Turtle Bay. The green and brindled landscape nurtures a complex of aquatic insects and snails, and the fish, river otters, birds, and fisherfolk they support. The riparian woods house red-shouldered hawks, woodpeckers, and the numerous birds that nest in the cavities they excavate.  Quiet inlets make restful wintering grounds for geese and hundreds of ducks including mallards, ring-necks, shovelers, and teal. Herons and egrets stalk the shallows, and kingfishers plunge into clear pools. Out in the river’s main current golden-eyes dive for bugs while grebes and red-coiffed mergansers chase fish. At Turtle Bay nature quietly offers a fundamental experience of life–its giving and its taking back, its patterning and variety, its beauty.

Barrow's Goldeneye Pair

Barrow’s Goldeneye Pair

But the wealth of Turtle Bay is not just the bend in the river. The bay is part of a corridor. Just as the Bird Sanctuary Loop is part of the larger River Trail, the Bay and its wildlife are part of the flowing water and the riparian woods, upriver and down. Each fall thousands of yellow warblers follow the river, scouring the riverside trees for insects to fuel their long flights to wintering grounds in Central America. Tanagers flock through, the males’ flame-red heads eclipsing into their yellow-greens of winter, as they gorge on the ripened grapes espaliered on towering cottonwood trees–again, fueling long flights south. Swallows–the orange-rumped cliff swallows that build homes under the Sundial Bridge, the shining blue tree swallows and violet-greens that nest in old woodpecker holes, and the rough-winged swallows that make homes in weep-holes at the Bella Vista water intake, all capture insects on the wing, skimming the river surface or circling high in the sky, first here where they hatch and then all along the river as they migrate. Redding’s famous eagles have fledged twenty eaglets at Turtle Bay; they, too, travel the corridor, both seasonally and a few years ago to try nesting downstream at Riverview Golf Course, where they fledged young but lost three nests before returning to their more reliable home at the Bay.

Redding Eagles

So far the Sacramento River corridor remains largely free of commercial development, allowing clean bywaters and riverine woods to grow the bugs that feed the fish and birds and other riparian life. Upriver from Turtle Bay the woods still flourish up to the dams, perhaps most broken at Redding’s Rodeo grounds, where the thin riverside forest has received a strip of welcome
replanting. Downstream, aside from the development along Park Marina Blvd, the riverbanks are substantially verdant.

Redding Rodeo Grounds

Now the city is considering selling land at Turtle Bay for commercial development. As this is written, the City Council is pursuing the land sale, while unofficially assuring that the Bird Sanctuary itself will be retained and spared the pavement, at least for now. Unfortunately, the biology of the Bay stands to lose regardless, because its life runs up and down the river.

City Council has seemed genuinely interested in getting public input: should the sights and sounds of riverside plants and wildlife be retained with permanent, broad setbacks for riparian woodlands?  Should development be kept to areas that are already paved, perhaps diverted to Park Marina? Will a dressed-up Convention Center and more restaurants draw the revenue of visitors from the Bay Area and farther off? Ultimately, will selling riverine public lands for development improve the quality of life for citizens now and in the future?  Your City Council wants to know what you value. You can reach them through cityofredding.org .

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Brewer’s Blackbirds

By on October 27, 2021 in Birds, BirdWords
Brewer's Blackbird Male

Brewer’s Blackbird Male

We mostly see blackbirds in suburban settings, but they are not limited to our neighborhoods.  Blackbirds now returning to local parks and parking lots may have just finished a nesting season in the sagebrush of the Great Basin or in marshy alpine meadows.  But even when they’re here, it’s easy to overlook them.  They seem a common and ordinary part of the background, too plain to attract attention.

But the blackbird tribe is varied and beautiful.  Male red-winged blackbirds strike the eye with their bright scarlet wing patches.  Starlings, the stumpy-tailed birds in the group, shed their shiny black feathers for new winter plumage, a gala coat of black and brown speckles.  Brewer’s blackbirds look slightly more elegant–no speckles, and they stand more erect and seem more considerate in their movements.

Brewer’s blackbirds might be a soft brown, tip to tail.  Those are the females, matte-finished for camouflaged child-rearing.  Others might peer at you with a golden eye from glossy black feathers that gleam in sunlight with a purple and green wash.  Those are the ones you’ll notice, the males, designed by nature to catch the eye and perhaps draw predators.  It is the males’ hapless duty to guard the nest while the females incubate their young.

Blackbirds nest in colonies.  The first females to settle into nesting set the trend, choosing almost any sort of habitat, but mostly in brush or trees near water.  Other females select nearby sites to build their nests; they all incubate their eggs for about two weeks.  More like raptors than songbirds, sometimes Brewer’s blackbirds begin incubating before all the eggs are laid.  This results in eggs hatching over several days instead of all at once, a condition that typically favors the eldest nestlings if food gets scarce.

During incubation, the males chase predators from the vicinity and may bring food to their mates on the nest.  Once their young hatch, blind and naked, males and females together feed them insects along with some seeds and fruit, until the nestlings fledge and can feed themselves.

In winter, mated pairs may separate into the huge flocks that blackbirds often form for foraging and roosting.  But most will rejoin their partners for the following nesting season.

The ability of blackbirds to live in a wide variety of habitats–arid scrubland, high mountain meadows, cattails, golf courses, city parks–usually bodes well for species to thrive through changes.  It is not surprising that blackbirds are among our most numerous songbirds.

Still, they have not been able to escape the world’s massive declines in habitat.  In 1966 the global number of Brewer’s blackbirds was estimated at nearly seventy million, three and a half times California’s human population at the time.  Now the blackbirds, down to about twenty million, number just half our increased state population.

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