Navigation

Author Archive | Dan Greaney

It’s Parenting Season

By on April 28, 2018 in BirdWords
Black-headed Grosbeak Male

Black-headed Grosbeak Male

It’s spring, and the busier the birds and bees are, the better it is for all of us. Part of that busy-ness has to be raising offspring.

Birds take on rearing their children with all the variety and flair of feathers. Many young birds are brought up in two-parent nests; others just by mom, some just by dad; some are raised by foster parents; still others are grouped into “it takes a village” scenarios. There are numerous child-rearing styles. But no young bird prospers without substantial parenting in some form.

Black-headed Grosbeak Male Feeding Young

Black-headed Grosbeak Male Feeding Young

Billions of aspiring avian moms and dads are in this child-raising season right now. Most songbird pairs share their nesting duties. Typically, the female incubates and turns the eggs, and quietly chirps to the young, who learn her voice before they hatch. Males in some species spell their mates on the nest, but more often do guard duty, dive-bombing or distracting predators. Both parents feed the hatchlings, hunting down hundreds of insects and making scores of feeding visits to the nest every day. When the fledglings take wing, the male often shepherds them, while mom perhaps begins a second or even third nest.

Black-headed Grosbeak Female

Black-headed Grosbeak Female

Black-headed grosbeaks, colorful, big-billed birds, take the sharing of nest duties a notch or two farther than most species. When a dangerous jay or neighborhood cat approaches, the female readily joins her mate in harassing the predator, attempting to drive it from their vulnerable young. On his part, the male, with rare egalitarianism, undertakes an even share of egg incubation and nestling-warming. More noisily than his mate, he nests with what seems foolhardy flair; he sings loudly right from the nest, as if he can’t contain his proud papa-hood.

Black-headed Grosbeak Juvenile

Black-headed Grosbeak Juvenile

Unike the precocial ready-to-go chicks of turkeys, ducks and quail, hatchling grosbeaks are altricial—blind, naked, and helpless. Within two weeks, however, under their parents’ relentless feeding and guardianship, the babies are full grown and feathered, ready to try their wings.

Like so many of our nesting birds, grosbeaks are travelers, wintering in Mexico and nesting as far north as British Columbia. Like robins, they have adapted effectively to suburbs and parks. They prefer to nest near water where both trees and brush offer cover. The females weave loose nests, usually on outer branches no higher than a second story window. Both the male and female sing profusely, a tune and tone frequently likened to that of a tipsy robin. His song is especially loud and clear, waltzing through the woods any time of day.

These singers of the American West dine on seeds, insects, and fruit, happily foraging high above us mere walklings. They are, however, happy to descend to our level to empty our feeders of sunflower seeds. There we can enjoy their burnt orange plumage and oddly hefty bills.

0

Eggs Came First

By on March 31, 2018 in BirdWords
Western Bluebird Hatchlings

Western Bluebirds

Eggs came first. There. Now you know. Eggs were around long before there were chickens, or any birds at all.

Egg-laying dominates the history of vertebrates, who appear in the fossil record in FARMB order: Fish, Amphibians, Reptiles, Mammals, and Birds. Of them all, only mammals regularly practice live birth. The other classes all lay eggs, and seeming exceptions of live birth are usually illusions—the mother actually makes eggs, but she retains them in her body until they hatch, and then delivers her wrigglers to the outside world.

That little evolutionary trick can be quite useful. Here in California, for instance, the southern alligator lizard lays eggs. The northern alligator lizard, however, keeps her eggs inside. This allows her to move them to warm spots throughout the day, spurring their development. Where the warm season is short, that accelerated development can mean the difference between the young growing up enough to endure the coming winter or perishing quickly.

Birds, of course, have a premium on light weight, so retaining eggs in their bodies is not a good option. Indeed, in the service of minimal mass, most female birds develop only their left ovary, and even that shrinks to a speck outside the breeding season. During nesting season, however, that ovary is full and busy, typically producing an egg a day several days in a row—what chickens have been bred to do year-round.

EGGS

Initial bird development is similar to that of humans. The ovary releases a protein-rich ovum which can then be fertilized.

But at that point, where humans will feed their young placentally, birds must prepare a self-sustaining egg. The ovum gathers its golden protein-rich yolk, which in turn is joined by albumen, the egg white. The albumen consists of water and more protein for the developing chick. Uterine cells squirt that eggy blob with calcium carbonate, which hardens into the smooth shell that curves round the birds’ precious hope of life. Egg farmers know that sufficient calcium in the mother’s diet is vital to forming viable eggs. Where calcium is lacking, a mother bird may donate up to 10% of the eggshell from her own bones.

With the egg formed, other cells squirt the species’ pigmentation onto its surface. Only two pigments, a blue-green and a red-brown, create all the variety of patterns and colors on birds’ eggs.

American Robin Nestlings

American Robin Nestlings

Like reptiles, who often bury their eggs, birds that nest in cavities and burrows usually have white eggshells. More exposed eggs are often speckled into camouflage. But some, like robin’s baby blues, are strikingly uncamouflaged even though exposed to the world and its predators. This presents another chicken-and-egg question: Which came first, the parenting or the color? Can protective parents like robins simply afford colorful eggs because they are dutifully present to shield their young, or did colorful eggs come first, with their demand for attentive parents? Does care, then, create beauty, or does need evoke care in successful species?

Killdeer Eggs

Other questions abound. Some eggs are oval, even round; others are conical. The hypothesis that conical eggs roll in a circle, and therefore are more likely among cliff-dwelling birds, isn’t really supported by the evidence. Another hypothesis is that since round eggs require less calcium to coat them, while pointier eggs can pack more tightly for incubation, the two shapes offer competing advantages; or perhaps it’s just that birds with more streamlined bodies can more readily lay thinner, pointier eggs.

Northern Mockingbird Nest

Northern Mockingbird Nest

This time of year, the most numerous bird on Earth, the domestic chicken, supplies the goods for more questions that many of us enjoy: How did you dye your eggs? Where did you find that one? What’s for breakfast? Or the worthy observation: aren’t eggs amazing and beautiful!

0

Black Phoebes Make Doughty Neighbors

By on February 24, 2018 in BirdWords
Black Phoebe

Black Phoebe photo courtesy of David Bogener

Winter is not traditionally mosquito-buzzing or cricket-singing season. The bugs lie low, not with summer music but tucked mutely into a puddle or under a log or leaf, usually as eggs or larvae or pupae. They wait for the revolving Earth to point us sunward, waking them up and rousing the crescendo of photosynthesis that prospers life seasonally all over the planet’s surface.

Songbirds, of course, know these seasons at an instinctual level. Our summer birds head south to sunnier latitudes not to keep warm but to keep in grub. Flycatchers, who snag six-legged prey right out of the air for breakfast, lunch, and dinner, are particularly reactive to insect dormancy. Customarily, they enjoy Acapulco or similar resort destinations this time of year.

But there’s always a nonconformist. Come drenching winter rains, pounding hail, hard frosts, and coats of snow, one little flycatcher finds a way to live through winter right here in Northern California. The black phoebe is one of our pluckiest neighbors.

Black Phoebe with Spider

They are no shrinking violets, nor much vegetative at all. Although scarcely the length of your handspan, and dressed in buttoned-down black-and-white, they engage life with redoubtable effervescence. They abundantly sing out their name, phoe-be, phoe-be! as if announcing nature’s vitality on even a frosty morning. They fly-catch when flies—or moths or mosquitoes—are few and far between, and expand their hunt to snatch prey from blades of grass or the surface of ponds. They flick their tails incessantly as if life simply requires dancing. They wear just a hint of a punk ‘do in their headfeathers, just enough to keep more sedate heads wondering.

And they not only survive, they flourish. When spring comes with readier food supplies, pairs reunite, and the male takes his mate on a tour of possible nest sites, fluttering enticingly under bridges or shady eves, or in the cleft of a tree-sized boulder. She chooses a spot and builds a nest, a half-bowl of mud plastered to the selected vertical surface—possibly refurbishing a site that the pair used in prior years.

Black Phoebe Nest

Phoebes defend their turf, chasing off other insectivores and reserving the local winged protein for themselves and their nestlings. But plucky is not foolhardy. They will generally flee a hunting hawk. Still, they are known to harass a fox or cat, and have been observed chasing jays thrice their size to protect their helpless young.

Black phoebes have done well with people. As long as water is nearby, with its provision of insects for eating and mud for nesting, human development has multiplied the vertical surfaces that make continuing life possible for this hardy neighbor of ours. Keep an eye and an ear out: there is likely a clear “phoe-be, phoe-be” near you!

0

Christmas Bird Counts Create a History of Information

By on January 27, 2018 in BirdWords
Black-throated Gray Warbler

Black-throated Gray Warbler

It’s a team sport. It’s parallel play. It’s research. It’s art. It’s an exercise in hope. It’s a long cold day outdoors!

The tradition of Christmas Bird Counts was begun by Frank Chapman in 1900. People often do things because they don’t know what else to do, and Chapman wanted to provide an alternative to the then-popular Side Hunts—Christmas Day competitions to kill and gather the biggest pile of furred and feathered animals. It was the era when John Muir was chastising Teddy Roosevelt for expressing his love of animals by shooting them, and when the Audubon Society had recently formed to dissuade people from killing egrets so their plumes could adorn ladies’ hats. The Bird Counts quickly caught on.

From that first rudimentary count in 1900, in which 25 areas from Massachusetts to Pacific Grove, CA were surveyed by 27 people to tally a total of 90 species, the annual count has grown into a massive inventory of Western Hemisphere birds. Some 75,000 people now identify and count all the birds they can in over 2500 established circles. The circles are 15 miles in diameter. The counts are held between December 14 and January 5. Good-weather years can yield 60 million birds in over 2600 species.

Locally, bird watchers conduct four Counts. The oldest, the Redding Count, was begun in 1975. It extends from Shasta College through most of Whiskeytown Lake, and from Shasta Dam down to South Bonnyview Road. Up the road, the Fall River Count was established in 1984, and is always popular as a location where valley, mountain, and Great Basin species can be found in its open fields and abundant waterways. South of Redding, the Anderson and Red Bluff Counts abut each other where the temperate Central Valley provides winter homes to numerous songbirds and waterfowl.

Together, the four counts this year hosted 81 people covering a total of 109 miles on foot, 939 miles by car, and 13 miles by kayak or canoe to tally 165 species and 75,712 individual birds.

There are always some rarities on the counts, but this year had many. In addition to a wayward swamp sparrow from the eastern US, and a handful of mute swans, who are elegant but destructively ravenous invasives, the rare birds mostly seem to reflect warm weather. Kayakers on Redding’s stretch of the Sacramento River found a black-throated gray warbler and a Hammond’s flycatcher, both of whom are expected to be sunning in Mexico this time of year. A boater in Fall River found a red-breasted merganser and a red-necked grebe, who usually winter in temperate coastal waters. A burrowing owl in Anderson, and Red Bluff’s sage thrasher and white pelican are all pushing their wintering range northward.

Perhaps the warm weather, holding some southland birds here, is also keeping many of our traditional birds away, farther north. Fall River compiler Bob Yutzy reports, “The numbers of most species were down.” Low numbers are repeated throughout the North State. Brooke McDonald’s report on the Anderson count includes “We had 18 Mallards, which is shockingly low. The average is 132 and the previous low was 81. We had 25 robins and the average is 201.”

From Red Bluff Michele Swartout reports, “We have had little precipitation so far this winter season, which meant very little to no water in our local ponds and wetlands. The lack of waterfowl, in both species and quantities was very obvious during this year’s count.”

Bill Oliver, compiler of the Redding count, sums up his findings: “The species total was a high average, but the number of [individuals] was below average, as it has been for the other local Counts.”

While the ecological disruptions of a warming climate cannot be welcome, we can hope that for now our missing North State birds are temporarily elsewhere, perhaps discovered in other counts. National Audubon is compiling the data and, if wet weather doesn’t bring the birds in sooner, will be able to let us know before long.

0

North State Gold

By on December 31, 2017 in BirdWords
Lesser Goldfinch Male

Lesser Goldfinch Male

Nature offers relentless beauty, free—not for the taking, but still for enrichment. One of this season’s beauties is goldfinches.

If you hang a feeder with thistle seed out your window, then a dozen or more of these lemon cuties may well deck the twigs nearby. They’re tiny, just elongated ping-pong balls, but on a chill winter morning they can turn bare branches into a Christmas tree.

The birds are known as Lesser Goldfinches. “Lesser” because they are smaller than their cousin American Goldfinches, and because in summer the cousins have more stunningly bright plumage. But in winter the larger birds lose their brilliance, turning an amber tan, while the lesser goldfinches continue to shine.

As is common in birds, the males are the prettier ones. Their wings are black with small flashes of white, and they wear smooth black caps. Their greenish backs melt into bright yellow undersides. The females dress in similar colors, but muted and without the hat.

It is uncommon to see a solitary goldfinch. They are gregarious, hanging out together like teens at the mall, and filling the air with their wheezy chittering and trills. In their native western US and Mexico, they can be seen wherever the small seeds they thrive on are abundant. They scour sycamore pods high in city treetops; they flock through weedy lots and fields; and they congregate at feeders. Development does not seem to have reduced the presence of weeds or seeds, and the goldfinches are prospering.

Our North State climate is temperate enough that the goldfinches out your winter window will stay in the neighborhood for their spring nesting. Finches are singers, and a male will twitter and tweet until a female succumbs to his melody and allows him to perch by her. He will eventually begin feeding her, a consideration he will continue as she selects a nest site and does the work of construction. She is practical in this task, weaving her grassy cup in a leafy tree or shrub and lining it with fluff from flora or fauna, making a soft, warm bed for the naked nestlings.

The nest is usually just 4-8 feet off the ground. Keeping it low facilitates his food delivery to her while she incubates their eggs, and later, their exhaustive efforts to fill the bottomless pits of their annual handful of children. In under two weeks of incubation, the young hatch out scrawny and helpless, but strong enough to demand that incessant deliveries of seeds and insects be gathered from the neighborhood and fluttered up to them. In less than two weeks more they will be as big as their parents, feathered, and flapping awkwardly from the nest.

Lesser Goldfinch Female with Nestlings

Lesser Goldfinch Female with Nestlings

After a little more tending, the weary parents can take a break. Their energetic young flutter on, replenishing the local flurry of color and song, continuing the persistent beauty of the natural world.

0