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Nesting Season Showcases Variety in Bird Homes

By on May 8, 2016 in BirdWords

Bank Swallows

Mama bank swallow and her chick gaze out over the Sacramento River from their cliff-bank burrow – photo courtesy of David Bogener

Spring is in the air and birds are in the creative construction business. The homes they build, where they will lay and incubate their eggs and raise their young, come in many styles, shapes, and sizes.

The simplest is almost nothing – a mere scrape on the ground such as the Killdeer use—and is abandoned as soon as the eggs hatch and the precocious babies follow their parents and pick up their own food. More complicated is the floating platform, such as the rafts that Pied-billed Grebes construct on local ponds, allowing these swimmers to live their entire lives without ever setting foot on land.

Simple elevated nests are the familiar cups that many songbirds such as the beloved American Robin build in bushes and trees. A robin’s sturdy home is formed with twigs, then cemented with mud– so if you see a female robin with mud on her chest you can bet that her nest is nearby. Robin babies hatch blind, naked, and helpless, so she lines the nest with grass to make a soft cradle for the nestlings in the weeks that their parents fly food to them. Even after the young fledge, the parents continue to feed them for some time.

Bird nests are unique to each species, so the builder of an old abandoned nest can often be identified by the materials, size, placement, and other construction features of the nest. There’s no confusing the tiny, dainty hummingbird’s nest, woven of moss and spider webs, with the massive stick-built home of the Bald Eagle! I once observed a Bald Eagle in Seattle land on a sizeable tree branch and keep on flying, snapping the branch and heading off toward the nest the pair was constructing – no picking up old sticks from the ground for this mighty bird!

Many birds are cavity nesters, using holes in trees that they have chiseled out themselves or reused after the original makers have moved on. All of the woodpeckers excavate their own cavities, although sometimes even they will start housekeeping in a provided nesting box.

To a certain extent we can select nesting box tenants by sizing the hole in the birdhouse. Entrances up to 1 ¼ inch round will admit wrens, titmice, and nuthatches. Bluebirds and tree swallows will use 1 ½ inch doorways. Larger holes will invite the nonnative European starlings, and so are not advised.

Unusual cavity nesters are the Belted Kingfishers, who dig long tunnels in river banks to house their eggs and chicks, and the Bank Swallows, who seem to use their burrows in courtship. The males dig two foot tunnels into a riverbank cliff, and the females check the sites out before selecting a package deal of mate and burrow. Their cousins, the Northern Rough-winged Swallows, will similarly burrow or can be seen nesting in the weep-holes of the concrete Bella Vista water intake downstream from the Sundial Bridge.

The master architects of the local bird world build complex nests such as the hanging basket of the Bullock’s Oriole. The Bushtit builds a woven construction more like a long sock with a tiny entrance hole up above the ankle. When the parent birds come to feed their chicks, the sock does the shimmy as the babies eagerly take their meal.

So, enjoy the season and the beauty of its diverse lives and homes! With your eyes open maybe you will see a bird carrying a piece of material to line its nest, and you’ll know that parent birds are preparing to raise their young ones!

Article by Linda Aldrich

Please Don’t Kidnap Baby Birds

By on April 11, 2016 in BirdWords

Handling baby birds is appealing, but this killdeer would probably be better off left with its parents. More often than not, “A bird in the bush is worth two in the hand.”

Killdeer Chick

Spring is in the air, and soon, if not already, the birds will be paired up, laying their eggs and raising their babies.

The birds most of us are familiar with have Altricial babies. That means when they hatch they are helpless, naked, and blind. This is the Nestling stage. The parents will work very hard during this time to provide food for them. Within a couple of weeks they will have feathers and will be exercising their muscles by flapping their wings very rapidly.

The next stage is called Fledgling. At this stage, the young will drop to the ground and run around, getting more exercise and hiding where they can. They are only in this state for about a week, waiting for their wing and tail feathers to grow a little longer, which will enable them to fly up and travel with their parents to find food and learn the art of survival. The parents recognize the cries of each individual baby and continue to feed them.

While the fledglings are on the ground they get preyed on by cats, dogs and picked up by humans who think they are orphaned and need help. Most of the time, as long as pets are controlled, they don’t need to be “rescued.”

The other type of baby bird is called Precocial. When these birds hatch and dry off, they are ready to follow their parents and start foraging for food on the ground right away. Precocials include quail, pheasants, turkeys, killdeer, and water birds that are here in our area. The baby killdeer in this area seem especially susceptible to being picked up because humans mistakenly think they are orphaned. They’re small, fluffy, and are known to hatch in open areas like parks, where they come into contact with people more often than the other Precocial birds. The baby killdeer and their parents wander from spot to spot, eating whatever insects they can find. When they are threatened, the parents have a particular sound that tells the babies to hunker down and be quiet. The only way you can see them is if you accidentally flush them out. If that happens, just quickly leave the area. If left alone, the parents will signal the All Clear and everyone will start walking around again, ready to eat their fill of whatever insects are out there.

We all have the best of intentions when we see an animal in danger. However, before we intervene, it’s always best to make sure that the bird is really in need of help. Fledgling birds usually need to be left alone so that they can continue to be in the care of their parents. Infant Precocial birds have the best chance of survival if allowed to continue to be raised by their parents.

Keep your cats and dogs indoors or restrained, and try watching at a distance for about a half hour to see if the parents are around. You will find that many of these youngsters are OK just where you left them. If not, please call Shasta Wildlife Rescue & Rehabilitation at 530-365-9453 and get advice on the situation before you physically intervene.

Thanks to author Karlene Stoker of Shasta Wildlife Rescue and Rehabilitation.  To volunteer with Shasta Wildlife call 347-3630

Robins Grace our Days

By on February 27, 2016 in BirdWords
American Robin

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 on February 2, 2016 in BirdWords
Feral Cat Feeding Station

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.

BirdWords: Wood Ducks

By on January 23, 2016 in BirdWords
Wood Duck Female

Wood Duck Female photo courtesy of David Bogener

For those who observe them, it’s small wonder that six of the new gifts offered in The Twelve Days of Christmas are birds! Not mentioned, however, are some of our most stunning winter birds, the ducks.

Wood ducks are the kings of color— green, blue, chestnut, and goldenrod, their beaks and eyes in two shades of vermilion, all set off with bold blacks and whites and decorative plumes and pony tails. The hen ducks are less outlandish, dressed mostly in their camouflage grays, but still sporting a splash of dark aquamarine and a delicate white eye-ring that thins into a teardrop behind the eye.

As their name suggests, wood ducks favor wooded byways. They spend the winter in small flocks, often with just a few friends, resting and feeding in quiet water. They eat mostly plant material—seeds, acorns, berries, and weeds—gathered either in the water or on land. Along about January they pair up. Courting involves mutual preening, and shrill whistles and stretched wing-and-tail dance moves from the male.

Then in early spring the hen wood duck, like only a handful of other duck species, chooses a cavity in a tree to make her nest. She is far too big for woodpecker holes, so she will often lay her 10-15 eggs in the rotted out scar of a fallen branch, usually 30-65 feet up. She will prefer to reuse successful nest sites from prior years. Other passing hens may dump more eggs into her nest, and she will incubate and raise them all.

Once hatched, day-old ducklings face immediate challenges. If their nest-hole is deep in a tree trunk, they might need to climb vertically many feet, up to fifteen, to reach their nest entrance. But they have clawed toes and instinct to help them out. Once reaching the entrance they blithely drop to the ground outside. It’s a long fall but doesn’t seem to faze them. They pop right up and begin to follow their mother to the nearest water, a hike that may be over a mile on their little duckling legs.

In truth, things have gotten easier for wood ducklings. With extensive tree-clearing in the late 1800’s wood duck numbers plummeted. But the ducks readily accepted human-made nesting boxes, and now they are thriving. Most nesting boxes are close to the ground, so ducklings might drop eight feet instead of their historical fifty.

Wood ducks live year-round in wet woodlands along the West Coast and throughout the Eastern US, and will winter in Mexico and nest all along the US/Canada border. Here in the North State look for them in quiet woodland waterways such as those of Battle Creek Wildlife Refuge, Anderson River Park, and Turtle Bay.

Our Education chair Dan Greaney writes for the Wintu Audubon Society and wrote this post.