MYSTERY SOLVED FOR HORSE LOVERS

April 1, 2014

CALIFORNIA SCIENTISTS CALIM TO HAVE SOLVED THE MYSTERY OF HOW THE ZEBRA GOT ITS STRIPES..AND WHY. READ ON:

University of California, Davis
April 1, 2014

SCIENTISTS SOLVE THE RIDDLE OF ZEBRAS’ STRIPES
[editor's note: I presume this is not an April Fool's joke...]

Why zebras have black and white stripes is a question that has intrigued scientists and spectators for centuries. A research team led by the University of California, Davis, has now examined this riddle systematically. Their answer is published today, April 1, in the online journal Nature Communications.

The scientists found that biting flies, including horseflies and tsetse flies, are the evolutionary driver for zebra stripes. Experimental work had previously shown that such flies tend to avoid black-and-white striped surfaces, but many hypotheses for zebra stripes have been proposed since Alfred Russel Wallace and Charles Darwin debated the problem 120 years ago. These include:

* A form of camouflage
* Disrupting predatory attack by visually confusing carnivores
* A mechanism of heat management
* Having a social function
* Avoiding ectoparasite attack, such as from biting flies

The team mapped the geographic distributions of the seven different species of zebras, horses and asses, and of their subspecies, noting the thickness, locations, and intensity of their stripes on several parts of their bodies. Their next step was to compare these animals’ geographic ranges with different variables, including woodland areas, ranges of large predators, temperature, and the geographic distribution of glossinid (tsetse flies) and tabanid (horseflies) biting flies. They then examined where the striped animals and these variables overlapped.

After analyzing the five hypotheses, the scientists ruled out all but one: avoiding blood-sucking flies.

“I was amazed by our results,” said lead author Tim Caro, a UC Davis professor of wildlife biology. “Again and again, there was greater striping on areas of the body in those parts of the world where there was more annoyance from biting flies.”

While the distribution of tsetse flies in Africa is well known, the researchers did not have maps of tabanids (horseflies, deer flies). Instead, they mapped locations of the best breeding conditions for tabanids, creating an environmental proxy for their distributions. They found that striping is highly associated with several consecutive months of ideal conditions for tabanid reproduction.

Why would zebras evolve to have stripes whereas other hooved mammals did not? The study found that, unlike other African hooved mammals living in the same areas as zebras, zebra hair is shorter than the mouthpart length of biting flies, so zebras may be particularly susceptible to annoyance by biting flies.

“No one knew why zebras have such striking coloration,” Caro said. “But solving evolutionary conundrums increases our knowledge of the natural world and may spark greater commitment to conserving it.”

Yet in science, one solved riddle begets another: Why do biting flies avoid striped surfaces? Caro said that now that his study has provided ecological validity to the biting fly hypothesis, the evolutionary debate can move from why zebras have stripes to what prevents biting flies from seeing striped surfaces as potential prey, and why zebras are so susceptible to biting fly annoyance.

Co-authors on the study include Amanda Izzo and Hannah Walker with the UC Davis Department of Wildlife, Fish and Conservation Biology; Robert C. Reiner Jr., of the UC Davis Department of Entomology and the Fogarty International Center, National Institutes of Health; and Theodore Stankowich with the Department of Biological Sciences at California State University, Long Beach.
ZEBRA FACES

ZEBRA LOOKS AWAY

ZEBRA REARS
My zebra pictures were taken on the dry grasslands of Uganda in 2010. That was on a PIB organized trip that included more than two dozen mammal species plus lots of great birding from sunbirds to the Shoebill.ZEBRA ROLLS-MBUTO

ZEBRA SHOW REARS

ZEBRA TRIO--MBUTO

ZEBRAS TURN

Additional information:
* Read the study: http://www.nature.com/naturecommunications

TIS THE SEASON

March 30, 2014

HOUS-SHPPING
It’s not just about the nest box, but where that nest box is placed. This one happens to be in a patch of oak savannah at about 3000 in the western foothills of the Oregon Cascades. It’s surrounded by open meadow and rolling hills that drop sharply down to a year-round stream. No humans live within a mile of the place and it’s back from the highway. No pesticides, no toxics. Just the sort of neighborhood where you’d raise your family if you were a bluebird.
wb-nst bx1
This nest box is on the fence of a tiny garden behind a row of town houses. It faces a busy sidewalk next to a busier parking lot adjacent to a dog park full of noise-making carnivores. Just the sort of avian slum where you’d expect the hardscrabble House Sparrow to eke out a living on bread crumbs and seeds.
HOSP-NST BOX
This drumming Red-breasted Sapsucker is still advertising for a mate. House-hunting will come later.
RBS-PST1
This pair of Flickers seem well-matched. She sits up and listens to his drumming. What more could a male Flicker ask for? And later in the day I saw them checking out nest holes in Lithia Park, Ashland, Oregon. Location, location…
FLKR-PAIRD
GHO-NESTING1 (1280x960) Look carefully to the left of the female Great Horned Owl. You’ll see the round, white head of an owlet and its dark eye-rings. This is at least the fourth straight year a pair of GHOs have used this nest near Ashland. Whoever first built that nest did a great job; owls don’t build their own nests but “borrow” or squat in what they can find.
MAGEE MARSH
PIB will be present at the Magee Marsh bird festival again in early May. Here are some nest pictures fro last year. This female Woodcock nested in a weedy strip along one side of the very busy parking lot.
woodcock nestShortly after they hatched before a group of wondering birders, mother Woodcock led her quartet of newly dried fuzz-balls into the nearby Magee Marsh woods where they quickly vanished from view.P1570600

Finding a place to raise your children is always emotional. This pair of Ohio Tree Swallows is a case in point.TRSW SCREAM

And, finally, this location seems perfect for Great Blue Herons. It’s at least the third straight year the nest has been used. It sits high in a cottonwood above Neil Creek, facing Oak Knoll Golf Course southeast of Ashland.

GBH-NST1

HERE IN ASHLAND, OREGON, THE KLAMATH BIRD OBSERVATORY IS SPONSORING OUR FIRST-EVER MOUNTAIN BIRD FESTIVAL. IT IS MAY 30-JUNE 1. WHITE-HEADED WOODPECKER, CALLIOPE HUMMINGBIRD, WESTERN SCREECH-OWL, SANDHILL CRANES ON NESTING GROUNDS, BOTH EAGLES, NESTING OSPREY, ACORN & LEWIS’S WOODPECKERS, MOUNTAIN BLUEBIRD AND CHICKADEE, HERMIT AND MACGILLIVRAY’S WARBLER, CASSIN’S FINCH AND VIREO, BAND-TAILED PIGEON, BLACK TERN, RED-BREASTED AND WILLIAMSON’S SAPSUCKERS, GREEN-TAILED TOWHEE, LAZULI BUNTING, AMERICAN DIPPER, WRENTIT, TOWNSEND’S SOLITAIRE–SOME OF THE BIRDS WE EXPECT TO SEE. WITH A LITTLE BIRDING MOJO WE CAN ADD GREAT GRAY OWL, SOOTY GROUSE, MOUNTAIN QUAIL, NORTHERN PYGMY-OWL, SWAINSON’S HAWK, EVENING GROSBEAKAND NORTHERN GOSHAWK.

PIGEONS AND ALEXANDER WILSON’S GHOST

March 4, 2014

The shade of America’s first great birdman is restless today. It’s been more than two centuries since Wilson, a self-exiled Scot, began publishing his color descriptions of all known North American birds. One of those, still very much alive, was the Passenger Pigeon.
Earlier this week I saw the living, closest cousin of the Passenger Pigeon, in my own garden here in southern Oregon. It was a lone Band-tailed Pigeon.BTP IN MARCH Note the iridescent patch on the bird’s nape. Many members of the pigeon/dove family have similar coloring. So did the Passenger Pigeon.
I blogged earlier about seeing Band-tails in my garden this winter. In six previous years I had no record of Band-tails after Nov. 5 or before March 5. This year they’ve been around occasionally in both January and February, now on March 2 as well.
I attribute this presence to the non-winter we’re having. After one heavy blizzard on Jan. 5 and two more weeks of freezing cold, winter seemed to dissolve. We began to get occasional light rains, and winds from the south. Most days the high is over 50 degrees. There’s no mountain snowpack. Our local ski resort at 6500′ on Mt. Ashland never opened this year and now is defunct. Lakes at 4500-5000′ are unfrozen, full of ducks, coots and geese instead of snow drifts. I now see Western Bluebirds hunting meadows at 4500′ in full sun. It’s been so dry that a Rough-legged Hawk has wintered at Howard Prairie which should be an icy marsh this time of the time.

A CENTURY AFTER EXTINCTION
This year marks the sad centennial of the death of the last living Passenger Pigeon. Killed off by widespread gunners’ slaughter and manmade habitat destruction. When he drew the bird two centuries ago Wilson would never have imagined its coming demise:PASS-PIG-WILSON On this page from my copy of Wilson’s American Ornithology you see his image of the bird.
He wrote, “…the most remarkable characteristic of these birds is their associating together, both in their migrations, and also during the period of incubation, in such prodigious numbers, as almost to surpass belief; and which has no parallel among any other of the feathered tribes on the face of the earth, with which naturalists are acquainted.”
From prodigious numbers to extinction in one century.
Wilson described watching one Passenger Pigeon flock move across the Ohio River in Kentucky: “the Pigeons, which I had observed flying the greater part of the morning northerly, began to return, in such immense numbers as I never before had witnessed…The were flying, with great steadiness and rapidity, as a height beyond gunshot, in several strata deep…From right to left, far as the eye could reach, the breadth of this vast procession extended, seeing every where equally crowded…I took out my watch to note the time, and sat down to observe them. It was then half past one. I sat for more than an hour, but instead of a diminution of this prodigious procession, it seemed rather to increase both in numbers and rapidity…I rose and went on. About four o’clock in the afternoon I crossed the Kentucky river, at the town of Frankfort, at which time the living torrent over my head seemed as numerous and as extensive as ever.”
Finally, Wilson tries to calculate the size of the Passenger Pigeon flock he had seen. His conclusion: “two thousand, two hundred and thirty millions, two hundred and seventy-two thousand Pigeons!”
In figures: 2,230,270,000 Passenger Pigeons in a single Ohio/Kentucky flock. A century later : 0.

BRING BACK THE PIGEON?
Now the very much alive Band-tailed Pigeon may give Alexander Wilson’s ghost some rest or further unrest. The Band-tail is at the heart of an effort to bring the Passenger Pigeon back from extinction. Read all about it in Nathaniel Rich’s amazing piece in the recent New York Times Magazine. Click here for the link.

I am not even sure how I feel about his plan to revive the dead. And I am even less certain what Alexander Wilson might think.

JUNCO YES, ‘JUNK BIRD’ NO

February 26, 2014

Nature has seen fit to populate North America with more Dark-eyed Juncos than humans. An admirable choice to my mind.junco brite
Around here the Junco breeds in both the Siskiyous and Cascades, in conifer forests mostly above 4000 feet. In San Francisco they breed beneath the transplanted pine and cypress, just above sea level.
Click here to find a nice article on what we know about Juncos and what they may tell us about our fellow primates.

ROETHKE ON THE HERON; AND WHY IS IT ‘PLUMAGE?’

February 24, 2014

“The Heron” by Theodore Roethke

The heron stands in water where the swamp
Has deepened to the blackness of a pool,
Or balances with one leg on a hump
Of marsh grass heaped above a musk-rat hole.

He walks the shallow with an antic grace.
The great feet break the ridges of sand,
The long eye notes the minnow’s hiding place.
His beak is quicker than a human hand.

He jerks a frog across his bony lip,
Then points his heavy bill above the wood.
The wide wings flap but once to lift him up.
A single ripple starts from where he stood.
GBH N PLUMES

This photo of a Great Blue Heron in his (or her) spring finery certainly shows why we call bird’s feathery outer wear, their “plumage.”

TIME TO ARREST DEVELOPMENT IN THE ANDES

January 10, 2014

Here at PIB we have come up with a way for you to save money on your next trip by making a tax deductible donation. Your $100 donation goes to Rainforest Trust. They will then use it to save a rapidly developing section of Peru’s highlands. And they have matching grants that will quadruple your gift. You get the tax deduction and we will give you $100 off any trip you take with us in the next 2 years. This is described as a win-win-win, we believe.

Here’s a map of the area we’re helping to preserve:Peru-rainforest park map The Peruvian government has pledged to turn the land into two national reserves once enough land is taken out of timber and agricultural use. The area is known as Sierra del Divisor.

Click here to find out how the donation and discount work together for you and the Peruvian rainforest. By the way, your $100 will actually lead to saving 800 acres from despoliation and exploitation.

Click here to read more about Sierra del Divisor and its species diversity.Goeldis_monkey_-_butterfly_lunch_-_big-240x153 This is a Goeldis’s Monkey, a threatened species, and one of sixteen primate species found in Sierra del Divisor.

VersicoloredBarbetLelisright Lelis Navarette, one of the superb regional guides we work with, took this picture of a Versicolored Barbet. It is one of over 550 bird species found in the highlands of Sierra del Divisor.

We’re talking wondrous species diversity: 38 medium and large-sized mammals (20 of them threatened) including giant armadillo; 10 endemic plant species with likely many more to be discovered among the 3500 species thought to survive in the area; at least 3 known endemic bird species with much exploration still undone; 300 fish species and over 100 reptiles and amphibians. All these beings depend on human intervention on their behalf for survival.

If you decided to help, PIB will give you our gratitude and our discount.

CALIFORNIA DREAMIN’ FOR NEXT SEPTEMBER

January 9, 2014

I will be leading a trip along the California Coast next September. It will be at the height of shorebird migration: Black Turnstone, Wandering Tattler, Red-necked Phalarope, Surfbird, Marbled Godwit, various sandpipers and plovers. Click here for itinerary.
Of course, we will cruise along Big Sur, a magnificent coastal highway, in search of North America’s largest bird (by wingspan).CONDOR3

CONDOR4
These Condor pictures were taken on the same route a couple years ago. There are now more condors flying free than are in captivity. A remarkable story of saving an endangered species that once got down to less than 20 individuals.
CONDOR2

CONDOR1

CONDOR WING TAG

CONDOR OVERHEAD
Click here to see what’s up on the Ventana Wilderness Society’s CONDOR CAM.

The trip will also take us in pursuit of California’s two endemic Corvids (no other American state has even a single endemic): Island Scrub-Jay and Yellow-billed Magpie. TOWA IN TREE Other hard-to-find birds we will seek: California Gnatcatcher, Oak Titmouse, Nuttall’s Woodpecker, California Thrasher, Hermit Warbler, Hutton’s Vireo, Heermann’s Gull and Cassin’s Auklet. Come enjoy some California sun and birding.CALIF SEPT.7 014

OUR MAN MAX

November 27, 2013

52013_1762463139163_5908045_o133488_489455257909_3142720_oThis is our man, Max Shefte-Jacobs, moving downhill faster than a Cooper’s Hawk.

196874_1007010293314_2644_n Max has been a member of national and regional Telemark ski racing teams in the past decade. He was first named to the development team as a 16 year old. Still a mere whippersnapper by the standards of some of us here at PIB, Max is our veteran web-meister. He makes the website live, our Facebook page look-worthy and tweets to the world like a hungry sparrow.
Next time you’re on the slope and something whizzes past like a Prairie Falcon after a pocket gopher, that was probably our man Max!

Here’s how our modest man Max himself describes his competitive career: “Last big event was in 2008 for the Telemark world cup championships in Sugarbush VT where I placed between 26 and 30 in three days. Then I was on the US Development Telemark Ski Team. I also raced at telemark nationals a few years in the top division. As a junior I got a lot of top fives in any telemark event I could get to including nationals before leaving the juniors at 16.”

SAVING THE LAND AND THE BIRDS

November 14, 2013

The Partnership for International Birding and the Rainforest Trust are working together to preserve some of the precious remaining native habitat in northern Columbia. This species-rich rainforest is in the Serrania de Perija, a 200-mile long mountain range that has peaks over 10,000 feet high. This is the northernmost finger of the Andes.
The area is home to numerous endemic bird and plants species. Not extensively explored, the area is expected to yield many more new species over the coming years.columbia map

The donations from PIB are part of our commitment to birds, our birding friends and the planet itself. We not only want our birders to see many birds but we want to be sure those birds and their habitat are still around for our grandchildren’s grandchildren. The best way to do this is own the land. Thus we have made a $3000 donation to Rainforest Trust and are hoping to make that a total of $5000 in the new year, insuring the Trust’s ability to buy 100 acres in the Serrania. Director of the Rainforest Trust, Dr. Paul Salaman, says the Partnership for International Birding helped to get the ball rolling on this project.RAINFOREST TRST

PIB has made the first targeted donation for the Serrania project and that will enable the first land purchase in that area. You could say we’re in on the ground floor, high in the mountains.

We at PIB are very pleased to be working with the Rainforest Trust (formerly the US-World Land Trust) in supporting their efforts to preserve wilderness for bird and wildlife conservation. We truly want to thank our trip participants and other conservation partners for supporting this effort.

WHAT’S THERE?

Much of the forest and paramo has been burnt, logged or planted in exotic trees. But enough remains that fragile ecosystems can be saved. ProAves has recently surveyed the area.

Studies have relocated the two endangered and endemic species, the Perijá Thistletail and Perijá Metaltail, and established the Perijá Brush-finch, while finding several new bird species for science, including a new Atlapetes Brush-finch, a new Scytalopus Tapaculo, a new Megascops Screech-owl, and a Cranioleuca Spinetail. Several other taxa endemic to the Perijá mountains are almost certainly separate biological and phylogenetic species (i.e. the Rufous Antpitta Grallaria “rufula” saltuensis, the Oleagineous Hemispingus Hemispingus “frontalis” flavidorsalis, to name but a few).
asthenes PERIJA THISTLETAIL, Asthenes perijana. This small overbird is found nowhere else on earth. It’s closely related to some canastero species found further south.

Despite its unique fauna and flora, no protected area yet exists in Colombia’s Serranía de Perijá. So we and our birding friends can now know that we are helping begin an urgent project that will protect, for the first time, an endangered habitat and the wide variety of species that depend on it.

Click here to learn more about Rainforest Trust’s Serrania project.

TALKIN’ TURKEY

November 7, 2013

The American Wild Turkey is in trouble. Like the Bobwhite before it, the Wild Turkey is experiencing a sharp population drop in the southeastern U.S. where its population was once the greatest.
The latest “Audubon” magazine summarizes what is known about the turkey troubles. State after state report declines of 25 to 50% in turkey populations. And these are game birds “carefully” managed. The article is NOT available online.
Causes? Not clear but habitat lose may be playing a part. In some areas forests are invaded with driveways, houses, swimming pools, rats, cats and free-ranging dogs. Climate change is bringing more formerly tropical disease northward as well. West Nile was a complete surprise when that virus hit the U.S. in 1999. This spring a Wild Turkey in Michigan tested positive for the virus. It is not known how deadly the infection would be in that species. We already know that Corvids are especially susceptible.
Click here for the 2012 “Southeast Wild Turkey Population Decline Study.” It is a progress report as the study continues. This preliminary study seems to indicate that turkey populations went through increases in the past fifty years in southern states due to human intervention and now there may simply not be enough habitat for the current populations. Reproduction rates may have fallen due to crowding or other causes undetermined.
Here in the western U.S.(California and Oregon) the Wild Turkey has been introduced for hunting and in many areas the population is increasing. Here in southern Oregon they compete with gray squirrels, Brewer’s Blackbirds and mule deer as the most often observed wild creature in town.
wild turkeys


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