International Vulture Awareness Day 2017

Turkey Vulture

The first Saturday in September each year is International Vulture Awareness Day.

Vultures are an ecologically vital group of birds that face a range of threats in many areas that they occur. Populations of many species are under pressure and some species are facing extinction.

The International Vulture Awareness Day has grown from Vulture Awareness Days run by the Birds of Prey Programme of the Endangered Wildlife Trust in South Africa and the Hawk Conservancy Trust in England, who decided to work together and expand the initiative into an international event.

Turkey Vulture Adult and Juvenile

Turkey Vulture Adult and Juvenile

It is now recognised that a co-ordinated international day will publicise the conservation of vultures to a wider audience and highlight the important work being carried out by the world’s vulture conservationists.

On the first Saturday in September, the aim is for each participating organization to carry out their own activities that highlight vulture conservation and awareness. This website provides a central place for all participants to outline these activities and see the extent of vulture conservation across the world. Additionally, it is a valuable resource for vulture workers to learn about the activities of their colleagues and to perhaps develop new collaborations or exchange information.

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Birds Pull Out Their Winter Coats

Bald Eagle Juvenile

Bald Eagle Juvenile photo courtesy David Bogener

What’s up with our backyard birds? Where are they?

You may have seen them over the last months busily carrying load after load of insects to feed their ravenous nestlings, then being raucously pursued by fledglings demanding yet more food – sometimes with two or even three batches of babies through the season. All this effort has taken a toll on the adult birds’ feathers and now, despite the daily care they have taken preening and cleaning them, the feathers are worn out. The birds are lying low during their molt – the annual or twice yearly loss and regrowth of feathers done by most songbirds. But don’t expect to catch a glimpse of bald birds – each worn feather becomes loosened in its socket and is pushed out by the growth of a new feather.

The process takes from 5 to 12 weeks for songbirds, after which some will appear in winter plumage quite different from the bold patterns some males sport in summer. For example, American Goldfinch males are bright canary yellow with bold black accents during the breeding season, but become a quieter butterscotch color, much like females and juveniles, in their winter garb. Similarly, you may see a male Western Tanager that has lost his gaudy orange head feathers and exchanged them to the muted gray of a female before starting the long, dangerous migration to Costa Rica for the winter.

Bald Eagle 4 Year Old

Bald Eagle Sub-Adult photo courtesy David Bogener

Other groups of birds go about the molt differently. Ducks, geese and some other water birds go through a rapid “synchronous molt”. They change their feathers quickly in a period as short as two weeks which renders them flightless for that period. This seems like a risky business – but researchers have deduced that since these birds are heavy relative to their wing surfaces, losing a few feathers at a time would seriously hamper flying ability, so they get it over with as quickly as possible and minimize the length of time that they are especially vulnerable to predators.

Raptors (eagles, hawks, falcons and their kin) “make their living” on the wing and can’t afford to suffer periods of impaired flying abilities. These birds may take as long as two years to complete a molt. The loss of flight feathers must be symmetrical or flying would be skewed. A woman who raised an owl that could not be released into the wild observed this in action. She reported that her feathered friend pulled a loose wing feather out and gave it to her, then immediately removed the corresponding feather from the other wing.

Bald Eagle Adult

Bald Eagle Adult photo courtesy David Bogener

To give young Turkey Vultures a good start, they don’t molt their flight feathers until they are two years old. The vultures soaring over minus a couple feathers are almost certainly adults.

In most birds, tail feather replacement is from the center of the tail toward the outer edge. Woodpeckers reverse this for a very good reason. Watch closely the next time you see one ratcheting up a tree and you will see that it braces itself firmly using its stiff tail feathers. The key for this is an inner pair of long feathers. Those are retained until the outer tail feathers have been replaced with fresh, strong vanes, keeping the woodpecker able to fully function searching for insects in the bark.

You may find a single feather in your yard – evidence that one of “your” birds has cast it off for a brand new set of feathers to get it through the winter or prepare it to head off to winter habitat in Mexico, Central America or South America. Enjoy the memento!

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pH for Public Health, and Dinner, too

Turkey Vulture Juvenile

Most of us observe external adaptations—the vulture’s naked head, its sharp beak, its capacity to soar. But the MD’s among us develop a familiarity with internal adaptations. Redding’s own Dr. Lang Dayton has provided further details in response to last month’s article on turkey vultures.

He refers to pH, the chemists’ and pool-owners’ 0-14 scale. In this scale, seven is neutral, like pure water. The extremes, as they are in much of life, are toxic. High numbers are alkaline, also called basic: ammonia measures eleven, and bleach twelve. Low numbers are acidic—think lemon juice, which stings, or sulfuric acid, used in drain cleaners, or Iron Mountain runoff, which has been measured at sub-zero pH levels.

Dr. Dayton writes:

The main reason vultures can eat almost anything is that they have the lowest gastric pH in the animal kingdom. Stomach acid protects all animals because it digests bacteria and other living organisms along with other proteins. Human stomach acid has a pH of two. It kills 99% of bacteria in contact with it, but people still get sick and can die if they eat enough contaminated or rotten food.

Turkey vultures’ stomach acid has a pH slightly above zero, lower than car battery acid and 100 times as concentrated as human gastric juice. It can dissolve metal, e.g. shovels, as well as digest nearly all organisms, including those that cause botulism, anthrax, rabies, cholera, hepatitis, and polio, along with other proteins. Vultures can eat just about anything that is dead and rotten, including animals that died from infections that, in turn, would kill most people who ate them.

By consuming rotten and diseased meat they decontaminate it, which helps to prevent the spread of disease to both humans and other animals.

When India experienced a massive vulture die-off in the 1980s, feral dog populations exploded and, with them, the incidence of anthrax, rabies, and other communicable diseases. Unlike vultures, dogs do not so thoroughly disinfect what they eat. Feral pets that eat carrion can acquire and spread disease from their meals.

One of the things that I used to teach Interns and Residents in the Mercy Medical Center Family Practice Program was that stomach acid protects all animals as it digests swallowed organisms along with other proteins, and that it is a bad idea to take medicines that suppress gastric acid when going to 3rd world countries. People lacking stomach acid get sick on 1/100th the dose of ingested organisms as normal people. Vultures, on the other hand, could feed on botulinum toxin. Give them enough gastric acid suppressants, however, and they would likely die after their next putrid meal.

Turkey Vulture

So thanks again to vultures for their good work, which seems to take both soaring on wings and going low on pH, and to Dr. Dayton for teaching us about the vultures’ gastro-intestinal virtue.

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Lassen Volcanic National Park Outing

Mount Lassen

Mount Lassen and Manzanita Lake

One of the best things about our annual Lassen Park campout is that we get to see several species of birds that are rarely, if ever, seen in the valley. Many of those species also nest in the park. According to their website, Lassen Volcanic National Park provides habitat for approximately 216 species of birds in which 96 have been known to actually breed in the park.

For those of you that have never been to Lassen Volcanic National Park, I thought I would post some photos I have taken inside the park of some of the bird and animal species we may encounter during our annual campout.

One of my favorite species is the Water Ouzel, more commonly known now as the American Dipper (Cinclus mexicanus). This is a photo I took at King’s Creek picnic area of an adult feeding its nestlings. Click on photos for full sized images.

American Dipper

and a short video of the nestlings begging for food and being fed.

Of course, LVNP has a great variety of woodpeckers on their bird list, eight of them known to nest in the area, including the White-headed Woodpecker (Picoides albolarvatus.) This is a male with some treats for the youngsters.

White-headed Woodpecker Male

 and a short video of the adults feeding the nestling and drumming.

We will hopefully see the rare Black-backed Woodpecker (Picoides arcticus) as well.

Black-backed Woodpecker

and maybe hear it drum!

There are Pileated Woodpeckers (Dryocopus pileatus) that hang out just adjacent to our campground in an old burn.

Pileated Woodpecker Male

And Red-breasted Sapsuckers (Sphyrapicus ruber) are common.

Red-breasted Sapsucker

Near Summit Lake we have been able to witness Williamson’s Sapsuckers (Sphyrapicus thyroideus) raising their young in a snag near the campground. The handsome male…

Williamson's Sapsucker Male

and the not as recognizable female.

Another of my favorite Lassen Park nesting birds is the Brown Creeper (Certhia americana)…

Brown Creeper

This is a video of the nesting activity of a pair of Brown Creepers at Summit Lake. Their nest is concealed in the narrow space behind loose bark on a tree.

Mountain Chickadees (Poecile sclateri) are one of the many secondary cavity nesters at the park. This is a nestling waiting to be fed at Hat Lake.

Mountain Chickadee Nestling

Also seen at Hat Creek, Red-breasted Nuthatches (Sitta canadensis) tending their nestlings.

Red-breasted Nuthatch

And the video accompaniment.

Other secondary cavity nesters at the park include the Pygmy Nuthatch (Sitta pygmaea)…

Pygmy Nuthatch

the Mountain Bluebird (Sialia currucoides), the male seen here…

Mountain Bluebird Male

and the Bufflehead (Bucephala albeola).

Bufflehead Female with Young

Lassen Volcanic National Park is one of the few places that this incredible cavity nesting duck breeds in Northern California.

This is a video of a female Bufflehead searching Manzanita Lake for a cavity to nest in for the following nesting season. She is in a snag, at least forty feet up!

American Coots (Fulica americana) raise their young at the park also. If you have never seen a American Coot chick, Manzanita Lake is a good spot to find them.

American Coot Chick

Since we’re checking out the youngsters of the park, I found this juvenile Clark’s Nutcracker (Nucifraga columbiana) at Bumpass Hell. Note the remaining flesh colored gape below the eye at the corner of the beak.

Clark's Nutcracker Fledgling

Other species that nest at the park include the Cassin’s Finch (Carpodacus cassinii). The male seen here…

Cassin's Finch Male
and the female.

Cassin's Finch Female

You would be hard pressed to miss the boisterous Steller’s Jay (Cyanocitta stelleri)

Steller's Jay

But if you are really lucky, you might find a young Spotted Sandpiper (Actitis macularius) at Hat Lake!

Spotted Sandpiper Chick

You gotta see this…

Or a Green-tailed Towhee (Pipilo maculatus) that also nests here.

Green-tailed Towhee

Of course there are more than just birds at Lassen Volcanic National Park. The park is home to approximately 57 species of mammals ranging is size from the tiny shrew to the North American black bear. We are most likely to see the Golden-mantled Ground Squirrel (Callospermophilus lateralis)…

Golden-mantled Ground Squirrel

the American Pika (Ochotona princeps)…

American Pika

and the Yellow-bellied Marmot (Marmota flaviventris).

Yellow-bellied Marmot

I hope this post intrigues you enough to consider joining us this year at Lassen Volcanic National Park for our 2017 annual campout. As always we will be camping with our friends and fellow Audubon members from other Northern California chapters. As with all of our activities, the Lassen Park Campout is posted on our calendar for more information. You are welcome to campout beginning Friday, July 28th, anytime past noon, or drive up Saturday morning to join us for the hike around Manzanita Lake.

Want more information on Lassen Volcanic National Park? Visit their website! And here is an interactive map of the park.

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Vultures Soar to do the Dirty Work

Turkey Vulture Adult and Juvenile

Summer is the season for soaring. Thermals, the warm air rising from the earth’s heated surface, can lift birds thousands of feet into the air with no more effort than spreading their wings. Larger birds, particularly raptors, for whom the quick flutter of small-bird wings would be physiologically impossible, are particularly famous for riding on thermals. The reigning champions of hot-air flight are, arguably, turkey vultures.

They’re ungainly, maybe disgusting. They can’t sing, only argue over food with a breathy hiss. They’re folklore symbols of doom and death. But supremacy in the air helps vultures prosper and decorate the sky through our sultry summer days. Some 90% of the soaring birds we see are apt to be not birds of prey but turkey vultures.

These vultures can be identified at a great distance. They hold their wings up in a V, a gift of their initial letter that hawks and eagles cannot replicate. The V shape, known in aviation as a dihedral, helps stabilize the birds in windy weather. When winter buffets the north state, the resident vultures ride the winds that replace the lazier-seeming currents of summer. Other turkey vultures will honor autumn tradition and head south—but they will still sail the winds, as they can ride as far down-continent as ever-blustery Tierra del Fuego.

Wherever they are, turkey vultures must soar to find their food with the most efficiency. Unlike most birds, they hunt with a keen sense of smell. Eagle-eyed predators can spot a salmon below the river’s ripple. Owls can hear a mouse squeak a football-field away. Vultures’ food, already dead, will not squeak or scurry for the ear or eye. Turkey vultures hunt mainly by smell. Their acute olfactory sense will not only find their carrion dinner, but will tell them whether it is too rotten to interest a civilized vulture. Indeed, while large owls, with their absent sense of smell, may gulp down a skunk, vultures will regularly discard at least the skunk’s scent gland.

But they really are not delicate diners. Vulture beaks are sharp and strong, but when particularly tough hides must be pierced, they may need to wait for early decay or a bigger predator to open the carcass. Since they will then be eating meals past their expiration date, and since they seem to prefer eating entrails from the anus up, vultures are heavily exposed to toxins. Fortunately, they are adapted to the dangers. Their naked heads not only keep feathers from being matted with contaminants, but also allow their skin bacteria, thicker and harsher than our own, to attack microbes in the meat, averting facial infection. The birds seem to be immune to effects from many biotoxins, and their own exceptionally virulent intestinal bacteria help them finish the job.

Their job is in fact a substantial service. Vultures find and scavenge about 90% of sizable dead animals in their range, reducing both disease and cleanup costs we would otherwise face.

Their condor cousins, with the rise of lead shot in carcasses and, longer term, no more mega-fauna to clean up, have been teetering on the edge of extinction for some time. Turkey vultures, on the other hand, perhaps responding to clearing of forests, an increase in roadkill, and a warming climate, have been extending both their breeding and wintering ranges northward.

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