Posts Tagged ‘Sandhill Crane’

Super Bowl Sunday 2012 – For the Birds

February 7, 2012

Sandhill Cranes Scoring a Touchdown

When we first saw them, the Raven was negotiating with the Golden Eagle about the carcass of a Snow Goose upon which the eagle was perched. Too far away to be certain, we supposed that the raven was explaining to the eagle that contributions would be gratefully accepted. The eagle appeared disinterested.

That was the tail end of our annual Super Bowl Sunday birding trip and was one of the highlights. The juvenile Western Meadowlarks added spice and the Black Phoebe and Says Phoebes weren’t bad either. And we saw numbers of Northern Harrier Hawks at work even though it was a Sunday. Northern Harriers lack religion.

We missed, by two days and three miles, the latest Aplomado Falcon visit. But several Kestrels made up for that, hovering like the best of helicopters and swooping down faster than any helicopter. Two Towhees rearranged last autumn’s leaves, White-crowned Sparrows posed, and Snow Geese swirled for no apparent reason. Except for the time the Harrier glided into their territory. That caused political unrest.

Snowing Geese

And 8,400 trumpets in the orchestra of evolution trumpeted. Aldo Leopold was right about Sandhill Cranes. They played several concerts during our sunset/sunrise visits. They go to bed earlier than the Snow Geese and begin their morning commute after the geese. The geese are last in, first out and the Sandhills don’t care. Sandhills aren’t as excitable as Snow Geese and they worry less. If Sandhills are the trumpets of evolution, Snow Geese are the violins and are, accordingly, more high strung.

We wanted to show you a photo of that Raven and Golden Eagle discussion but, as we set up the shot, a cretin who works at the refuge careened into the field in his big white pick-up, scared the eagle and the Raven away and stole the goose carcass for himself, unceremoniously pitching it in the back of the pick-up, leaving us with only back-lit photos of the eagle and raven flying away and leaving both of them without lunch. A strong letter of protest to the refuge will be dispatched. If that man needed the goose for food, we’re not paying him enough; if he dislikes Golden Eagles, he ought to have a desk job. Either way, good manners required that he wait for me to make my photograph before scuttling the negotiations between the eagle and the raven.

 

 

 

 

When Spring Trips North Again This Year

February 23, 2009
Lago Desierto, Patagonia

Lago Desierto, Patagonia

In the far reaches of the southern hemisphere the days are perceptibly shorter now.  The oceans and lakes surrender some of the heat they’ve stored over the summer and the daily temperatures begin to drop.  Conversely, in the southern reaches of the Northern Hemisphere, the first signs of spring are upon us.  Daylight hours are sensibly longer, temperatures are beginning their annual climb and the earliest and hardiest of plants have sent out tentative green.

In billions of birds, these signs stir primeval urges.

For instance, today, just to the west and high above us, Sandhill Cranes, the trumpets in the orchestra of evolution Aldo Leopold called them, are rising on thermals, circling and calling, then stretching into their V formation and soaring north.

It seems too early, but January and February here have been among the warmest on record so the birds may know something we don’t.  Or maybe it has little or nothing to do with the air temperature; perhaps this instinct to move is triggered solely by the tilting of the earth’s axis toward the sun. Possibly it is some of both; ancient pathways laid down in their genetic code coupled with the short term knowledge that the earth is warming and it is therefore safe to leave earlier.

Sandhill Crane

Sandhill Crane

There are other signs that winter is losing its grip.  The male House Finches that spent the winter with us are growing their bright red “attract a female” plumage, our feeders are being drained of seed more rapidly, at our store hummingbird feeders are selling even though it will be more than a month until the hummingbirds begin to arrive, and we are writing about the spring migration and looking for the hay fever medications.

Billions of birds migrate twice a year, some from the far tips of the southern hemisphere to the far northern tips of the northern hemisphere.  Passerines fly in great flocks to the boreal forest of Canada to breed.  Hummingbirds by the millions make the hazardous journey from Central America to North America.  Raptors of all types climb into the skies and head north. They’ve been doing it since long before there were humans to observe it, even long before the continents assumed their current shapes and sizes.  (For perspective, the first true birds appeared about 145 million years ago.  Modern birds had evolved and most survived the great K-T extinction at the end of the Cretaceous which wiped out the dinosaurs.  That was about 65 million years ago.  Homo Sapiens have been here for only about 250,000 thousand years.)

The earth 50 million years ago

The earth 50 million years ago

Science is not certain exactly how they do it.  Some elegant experiments have tried.  Perhaps it has something to do with the position of the sun in the sky?  No.  Make the birds fly only at night and they unerringly find their way home.  Maybe they navigate by stars?  No.  Make them fly only during the day and home they go.  Subtle fluctuations in the earth’s magnetic field?  Possibly.  But put them in a screwed up magnetic field and they orient in the right direction to go where they are supposed to go.  Tiny maps in an onboard computer?  Could be. but scientists have played games with bird brains and still they go home.

Most likely it is a combination of all of the above.  They fly thousands of miles and return to the same square foot of earth they left months earlier.  Some can even do it even though they’ve never been there before.  Many bird species migrate without parents teaching their offspring where to go, yet the youngsters get there all the same.  They fly in such numbers that they are visible as huge clouds on radar screens.

Weather Radar Image of Migrating Birds

Weather Radar Image of Migrating Birds

Of course, birds are stellar navigators.  Raise homing pigeons in a mobile loft and send them off to forage one morning and then, while they are gone, move their home to the next county and they will show up at the relocated loft in time for dinner.  Nobody knows for sure how they do that either.  Not all of life’s questions have been answered.

Wonder is an underrated emotion and, as we’ve often said before, calling someone a “bird brain” is not an insult.


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