Author Archive | Dan Greaney

Robins Grace our Days

By Dan Greaney on February 27, 2016 in BirdWords

American Robin

John James Audubon reports that when at the age of eighteen he emigrated from France to the New World, “The first land-bird seen by me, when I stepped upon the rugged shores of Labrador, was the Robin, and its joyful notes were the first that saluted my ear… I could scarcely refrain from shedding tears when I heard the song of the Thrush, sent there as if to reconcile me to…the barren aspect of all around.”

While the age of birdsong eliciting tears has largely been buried by hastier technologies, Audubon’s raw experience is something most of us can still find in our own backyards and parks. Reported to be the second most numerous land bird living in North America today, the robin remains a soulful beauty, so common as to be almost overlooked.

As Audubon noted, the robin is a thrush, a family that includes bluebirds and several speckle-breasted singers of deep forests. More than any other thrushes the robin has accommodated human civilization. It thrives wherever there is moist earth, trees and shrubs, and a supply of fruit, berries, and insects. From those places it seems to greet us vigorously. Its song, often the first in the morning and the last at night, is not the haunting flute of its thrush cousins but rather a lengthy and cheerful burbling punctuated with lively chirps. Nor does the robin confine itself to woodsy shadows. Most of us see it out in the open, pulling worms from a rain-wet lawn, or gracing the day from a skyward perch.

Robins range over most of the continent, wintering across the US and well into Mexico, and extending their nesting range high into Canadian forests. Redding often hosts large flocks in winter. Sometimes thousands of them will roost together high in cottonwood trees along the river, joining in avian lullabies at dusk—a treat for Turtle Bay visitors. As spring comes, the winter migrants will fan back northward. The flocks disappear. The locals pair up.

Alert observers may notice clear differences among different robins. All adults have yellow bills, and in some birds the white around the eye is striking. Their breast feathers may show a deep chestnut color, or brick red, or pale orange. Some birds will flash a glimpse of white at the corners of their tails. In general, female birds are paler, which serves well as they tend the nest. Other differences occur geographically. Robins are grouped into seven subspecies, but they interbreed, so their differences are not abrupt but rather blend from one to the other.

Females build the nest, mostly of grass and mud. She incubates 3-5 blue eggs for twelve to fourteen days. She will leave the eggs briefly to find food, but the male feeding his mate on the nest has been observed. Both parents care for the young through their fledging in another two weeks. Then the male may continue to look after the fledglings while the female, if weather and the insect supply permit, starts a second or even third nest.

Feral Cats Drive Songbird Decline

By Dan Greaney on February 2, 2016 in BirdWords

Feral Cat Feeding Station

Cats can be great pets, low maintenance purring machines. Unfortunately, they are also active and effective predators.

There are many ways for birds to die. Among the human causes in the US, window collisions may kill a billion birds a year. Cars kill a fraction as many, some 200 million. Pesticides, power line and cell tower collisions, wind turbines, hunting, and oil spills may kill another 200 million.

But the big killer in the US is cats. It is estimated that outdoor cats kill 2.4 billion birds a year in our country. With the exception of habitat loss, this number dwarfs all other current human-caused bird mortality combined.

Many of the studies are small, but they reveal a grim pattern. Cats kill nearly 50% of suburban songbird fledglings. Pet cats average one wildlife kill per fifty-six hours outdoors. They eat or abandon most of their kills at the kill site, not on the owner’s doorstep – belying many owners’ hopes that their pet is too domesticated to follow its instincts. A University of Nebraska study pins thirty-three bird extinctions on cat predation worldwide.

Feral cats number between 30 to 80 million in the US, according to World Animal Foundation estimates. If their kill rate equals that of pet cats, simple arithmetic indicates kills of small animals – birds, lizards, voles, etc. – of nearly 8 billion per year.

Despite being an invasive species, domestic cats are often maintained in the wild. Well-meaning people develop feeding stations that create unnaturally dense colonies. These colonies turn city parks and neighborhoods into native species kill zones, contributing hugely to the declines of American songbirds.

Further, these feral cat concentrations create sinks for the spread of disease and suffering, Feline leukemia and panleukopenia are highly contagious, disabling diseases of outdoor cats. FIV – the cat version of the AIDS virus – spreads mostly through saliva in cat-fight bites.

People, too, are at risk from cat-spread disease. Rabies is found in three times as many cats as dogs, possibly because of their greater involvement with wild animals and the lack of vaccination.

The toxoplasmosis parasite, famous for warnings to pregnant women against cleaning cat litter, can infect any warm-blooded being but only reproduces in cats. Over 70% of cats are expected to carry the parasite at some point in their lives, and they release hundreds of millions of oocytes that can deliver the disease for years through gardens and parks where they defecate. In people, our immune system usually prevents symptoms. But the parasite attacks the brain and is associated with deafness, eye lesions, and a wide range of behavior disorders including Alzheimer’s, autism, obsessive-compulsive disorder, and schizophrenia.

Some solutions to these bird kill and public health problems are easy. Pet owners who keep their cats indoors will protect both wildlife and their cats.

Feral cat problems are tougher to tackle. Trap-Neuter-Release programs have been shown to be ineffective. Neutered cats still kill birds and spread disease, and neutering efforts do not keep pace with the influx of new cats. A single breeding pair can produce 400,000 offspring over seven years.

US governments spend over $50 million a year to reduce the problems posed by feral and stray animals. In Redding, city land is being used to support feral cat colonies.

Climate Change is Beginning to Take Its Toll on Bird Populations

By Dan Greaney on June 3, 2015 in BirdWords, Conservation, In the News

Western Meadowlark

Last month I wrote about insect-eating birds swarming into Shasta County to raise their young. Unfortunately, I was indulging in a bit of optimistic nostalgia. The migration itself is as real as ever, but our nesting numbers are dismally down.

It can’t really be a surprise. Everything needs its habitat, and in actions that seemed reasonable, we have converted much wildland to more prosaic purposes. But the yellow-headed blackbird can’t nest where the marsh is drained, nor can the meadowlark make a home where grasslands are converted to row crops. The thrasher can’t sing where the chaparral is cut for houses, or the pet cat kills its young. The kestrel can’t nest where old woodpecker holes have been cut down to reduce hazards, and the pygmy owl can’t stalk grasshoppers where the woodland is paved into yet another retail center.

Driving up the valley as a kid it seemed there was a hawk on every telephone pole. But we reasonably want produce, and farmers pragmatically maximize their production. So after forty years of our plowing through the lairs of fieldmice, gophers, and snakes, of course the hawk numbers are down; after forty years of pesticides to kill hungry insects, of course the songbirds are reduced; after more recent advances to mow right to the fenceline, of course the hedgerow birds are gone.

Unfortunately, our personal perceptions of too-quiet treetops, empty telephone poles, and vacant fencelines are confirmed by research around the globe. Complementing the 115 year old Christmas Bird Count, the North American Breeding Bird Survey has run each May since 1966. It documents declines of 40-60% in a quarter of our birds, and up to 96%, depending on the species and region.

And that’s what has happened already. Now farm produce is being bio-engineered to withstand yet more pesticides, and their application has begun. Climate change is beginning to take its toll. At current carbon emission projections, 314 of 588 species studied by Audubon will lose at least half their seasonal habitat within the lifetime of this year’s graduates.

Many birds will face challenges as seasons unsynchronize: hummingbirds can’t sip on flowers that have already fruited, and fields gone dry offer fewer insects to bring to the nest. Some birds will be unable to shift northward as quickly as this climate change is demanding—especially if they need vegetation that moves north more slowly. Those who successfully shift will encroach on existing nesting grounds; ravens, which eat eggs and nestlings, are already increasing in the arctic, and invaded tundra birds have no Farther North to flee to.

As in most places, in Shasta County we have not, to my knowledge, lost any entire bird species in recent history. But the music is fainter, the voices fewer. Not so long ago, when the canaries started dying we recognized a problem and acted on it. We should be so wise and disciplined today.

BirdWords: Snow Geese Flock to Central Valley

By Dan Greaney on January 10, 2015 in BirdWords

Snow Goose at Sacramento National Wildlife Refuge

My sister is not a bird watcher, but as she and her family drove back to the Bay Area after a Redding Thanksgiving we received her text: “What’s a big white bird with black wingtips?”

After confirming that they were near Willows and that there were many of the birds we told her “snow geese.”

Small wonder that the birds grabbed her attention. Every winter hundreds of thousands of them, in squealing tornadoes in the sky and squawking blankets over fields and ponds, inundate the Central Valley after nesting in the high arctic, mostly on the islands between Alaska and Greenland.

First the arctic story. The tilt of the North Pole toward the sun in the spring and summer creates a polar season in which the sun never sets, for up to as much as six months right at the North Pole. This abundance of daylight spurs plant growth, in which the grasses, sedges and algae lock great quantities of solar energy into their cells through photosynthesis. That energy is then available to feed geese and ducks and shorebirds by the millions. The birds eat either the plants or the hordes of invertebrates that eat the plants. It’s calorie-rich season, perfect for raising hungry offspring.

Snow geese typically lay a handful of eggs in a tundra tussock, usually in late May. The eggs hatch in some 23 days. Both parents then tend to the young, which follow them about, foraging on their own within a day of hatching. The goslings grow quickly, developing the strength to migrate south in the fall.

Spring snows can disrupt nesting, but mild weather has helped our Pacific flyway geese do very well over the last 10 years. Their numbers grew 53 percent from 2012 to 2013 alone, up to nearly 1.4 million.

In the Redding area, the geese and many arctic nesters find winter habitat at refuges like the Sacramento Wildlife Refuge in Willows. While some 95 percent of original Central Valley habitat has been paved, built upon or turned into farms, the refuges and unburned rice fields help compensate. Many farmers flood their fields through the winter, providing rich grazing and resting grounds that have helped geese thrive, perhaps to record numbers.

However, our drought limits the extent of field flooding both on farms and refuges. The birds, with less water available, squeeze into wherever the water is — a crowded condition that risks spreading disease. For the snow geese, nesting success may be countered with winter die-offs.

Still, in a time when so many species are in decline, the snow geese are flourishing. They remain a sight and sound that harkens to a wilder and inspiring time, and make it well worth a visit to the refuge or at least an open eye as you drive south on Interstate 5.

Note: The Wintu Audubon Society will be conducting a trip to the Sacramento Wildlife Refuge on Jan. 24. See our calendar page for all the information.

Send your bird questions to education@wintuaudubon.org

White-crowned Sparrows Are Regular Visitors to Redding

By Dan Greaney on November 30, 2014 in In the News

White-crowned Sparrow

Birds are among the most evident wildlife around the world. They sing, sport a crazy variety of shapes and sizes and live in all sorts of habitats. They’re also often colorful and can be lured into close-up viewing. And they live here.

In Shasta County, we have more than 250 species seasonally every year, plus another 50 species who have made cameo appearances.

One regular visitor that graces our parks and backyards every winter is the diminutive white-crowned sparrow. This ball of feathers, the size of a child’s fist, is perhaps our most common bird of brush and patio. It has a subtle beauty that unmindful people will easily miss.

Its underside is a plain gray and, like most sparrows, its back is a mottled brown. But its bill is egg-yolk yellow and its head is decked out in bold black and white racing stripes.

That yellow beak is short and chunky — good for cracking seeds. These sparrows are eager visitors to bird feeders, where they specialize in eating up grains scattered on the ground. A close-up feeder or a pair of binoculars will allow precise inspection of the black-and-white head, which can reveal where the bird travels to nest in the summer. If the black-line behind the eye continues forward of the eye, that sparrow likely nests in Lassen or the Northern Rockies, from Colorado through Montana and Idaho.

These birds have mostly passed through our area and are now wintering at a resort in Baja. If the black line stops at the eye, these travelers may nest as far north as the high arctic of Canada and Alaska, a journey of as much as 200 miles — no mean feat for little birds that often look like they have to work hard just to cross the yard.

Whether in Redding, Baja or Fairbanks, sparrows are brush birds. White crowns nest within a few feet of the ground, building a soft cup of plant material. As is the case in many species, the female picks the nesting site. She typically lays three to five eggs, and both parents feed the young until they fledge in a week and a half, and then a little longer to get them going.

If you notice a sparrow whose black and white stripes are replaced with reddish-brown and tan, you are looking at a young bird, just hatched last spring. If it can survive through winter, it will fly to its nesting grounds, grow adult feathers, and try its own hand at raising a brood or two before returning to your yard next fall.

Wintu Audubon provides the new BirdWords column. Please send your local bird questions to education@wintuaudubon.org