Posts Tagged ‘buffalo’

Lesser Prairie Chickens

April 26, 2010

Perhaps you’ve never been to the eastern plains of New Mexico. I can describe the scene for you in one word: Flat. Sparsely populated, sparsely vegetated, and sparsely sparse, it is a land of big horizons. Once, before courageous, stubborn, and perhaps misguided farmers and ranchers tried to wrest a living from it, it was all short-grass prairie. But Euro-Americans plowed it for dry-land farming and brought cattle to graze it. One look at it today, especially on a windy spring day when the dust blows, tells you that even if a cow once could have made a living on its over-grazed vastness, those days are long gone.

Before 1880, it was covered with buffalo grass and bison. Buffalo grass, and its cousins, blue grama grass and little bluestem grass, sustained the great bison herds of the southern plains for more than ten thousand years.

Capable of surviving all but the most extended droughts, short-grass prairie could survive neither the cow nor the plow.

Bison, on the other hand, helped the short grasses. They fertilized it, churned the soil so seeds could germinate, and they moved the seed around. In return, the grass, even with its low load of carbohydrates, provided succulent new shoots for the bison to eat.

The grass, evolved to a perfect fit for semi-arid land, could hold moisture a foot below the surface, even during hot, windy days and long dry summers. Timothy Egan wrote of it:

As long as the weave of grass was stitched to the land, the prairie flourished in dry years and wet. The grass could look brown and dead, but beneath the surface, its roots held the surface in place; it was alive and dormant. . . In turn, the grass nurtured pin-tailed grouse, prairie chickens, cranes, jackrabbits, snakes, and other creatures that got their water from foraging on the native turf.”

Contending Male Lesser Prairie Chickens

Only small islands remain and some of those small islands are home to the few remaining Lesser Prairie Chickens. We’ve destroyed about 92% of their habitat, killing about 97% of their population. Nobody knows for sure how many are left, but they once numbered, like the bison, in the millions. Today only thousands remain. Not only did we destroy their habitat, we hunted them like grouse. Of course, they are grouse.

They needed a nobler name.

Once they lived throughout western North America. Fossil remains from the Pleistocene Glaciation have been found in from Oregon to New Mexico. Today they live only in isolated pockets of sand sage or shinnery oak rangeland in extreme southeastern Colorado, southwestern Kansas, the eastern edges of the Oklahoma and Texas Panhandles and eastern New Mexico.

The males attract their mates – and hardy human watchers – on traditional display grounds known as leks. Often on knolls or ridges and always in areas of sparse vegetation, the males gobble and hop and display, raising their tails, erecting feathers, drooping wings, enlarging their eye-combs, stamping their feet and “booming” by expanding esophageal air sacs. The show starts an hour or so before sunrise and continues for two or three hours. The successful males copulate with as many females as possible before retiring for the day. Sometimes, they return for an early evening encore performance. The females retire to nests, which are usually within a mile or so of the lek, to brood and raise the young.

Lesser Prairie Chickens eat grasshoppers, leaves, flowers, and seeds, especially shinnery oak acorns. They, in turn, are eaten by hawks, eagles, Prairie Falcons, coyotes, badgers, snakes, and humans. Like other grouse, they burst into flight when startled and often fly when moving to and from their gobbling grounds, feeding areas, roosting sites, and loafing sites. Most flights are short-distance, low-level affairs with alternating wing-flapping and gliding.

But mostly they are gone now, victims of a human culture that produced a mind-set enabling Phil Sheridan, General of the U.S. Army to say,

The hide hunters will do more in the next few years to settle the vexed Indian question than the entire regular army has done in the last thirty years. For the sake of a lasting peace, let them kill, skin, and sell until the buffaloes are exterminated. Then the prairies can be covered with the speckled cattle and the festive cowboy, who follows the hunter as the forerunner of civilization.

It would have been better for the prairie chickens had Euro-Americans adopted a different attitude when we arrived on the short-grass prairies:

What is life? It is the flash of a firefly in the night. It is the breath of a buffalo in the winter time. It is the little shadow which runs across the grass and loses itself in the sunset. (Crowfoot, Blackfoot Indian.)

That little shadow might have been a prairie chicken.

__________________________

The photos of the Lesser-Prairie Chickens were taken last week by friend Linda Rockwell, who has a new blog showcasing her bird photography. You’ll find it here and many more photos of prairie chickens.

The bison photo is by Jack Dykinga of the USDA.

For more on the bison, short-grass partnership, see The Destruction of the Bison: An Environmental History 1750-1920, by Andrew Isenberg of Princeton.

For more on the Lesser Prairie Chicken and its relationship to short-grass prairie, see Hagen, Christian A. and Kenneth M. Giesen. 2005. Lesser Prairie-Chicken (Tympanuchus pallidicinctus), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/364 (Subscription required)

Cowbirds

January 3, 2008

It is time to write about cowbirds. No nice way exists to say this: they are parasites. They once multiplied at a prodigious rate in North America and may be endangering many other bird species. They are a menace. No one knows for sure how many reside in North America but the number exceeds 40,000,000 and may be as high as 80,000,000. Mostly they are Brown-headed Cowbirds although Bronze-headed Cowbirds live in the southwest United States.

brown-headed-cowbird-molothrus-ater.jpg

Cowbirds don’t believe in nest building. It is so much easier just to use someone else’s nest. Cowbirds also don’t believe in child rearing. It is so much easier to let someone else do it. But they do believe in fornication. The females are egg machines and the males love to fertilize all those eggs. Because they waste no time building nests or feeding their young, they have time on their hands and they use it for lust. In low density populations they appear to be monogamous but when population densities climb, the birds are promiscuous, polygynous, or polyandrous as the mood hits them. There is some evidence that monogamous populations flock together and that promiscuous populations flock together, leading one to the unforgivable comment, that birds of a feather flock together and we ask your forgiveness for making that unforgivable comment.

Female cowbirds are devious little birds. In order to find a nest to lay her eggs, a female will sit quietly and watch for other birds building nests; or she will walk around on the ground searching for nests in use; or she may flap her wings excitedly, perhaps trying to flush birds from their nests. When she finds a nest she lays her egg in it as soon as the nest-owner is gone. (The spotted egg in the photo is the cowbird egg.)

cowbird-agg.jpg

When the nest owner returns there is one more egg to brood, unless the cowbird has eaten one eggs already there. Often the cowbird egg hatches a day before the legal residents’, giving the cowbird a head start on its nest mates. The baby cowbird is a little bigger and a little noisier and ends up with more food. (The red-mouthed nestling in the photo is the cowbird.)

cowbird-baby.jpg

Not all birds put up with this. Robins and Grey Catbirds simply toss the strange eggs out of the nest. Yellow Warblers bury the cowbird eggs under a new nest lining. Others simply leave. Western Kingbirds, Eastern Kingbirds, Blue Jays, Cedar Waxwings and Northern Orioles almost always reject cowbird eggs. Interestingly, these are species which probably co-evolved with cowbirds and are on to them. But most songbirds reject cowbird eggs at a far lower rate. In one study, cowbirds successfully parasitized 83% of Indigo Bunting nests in the study area. Some species, such as Kirtland’s Warblers, Least Bell’s Vireo and Black-capped Vireos, already endangered, are at significant risk from cowbirds. Extinction is close at hand for those species and it will not take much to tip them over the edge.

Cowbirds prefer cities. Songbirds living in cities are more likely to have unwanted cowbird babies to raise. No one knows for sure why cowbirds like densely populated human urban areas although they do enjoy bird feeders and lawns are good foraging sites.

Not much is being done to control them. A few trapping programs exist. There is one in Texas. In 2006 that program trapped and “dispatched” 24, 293 cowbirds. Ominously, the report did not define “dispatched.” But 24,000 “dispatched” cowbirds out of a population of at least 40,000,000 cannot make much of a difference. The rest still have all that free time.

Once cowbirds were not such a problem for other birds. They lived only on the Great Plains where they followed the Bison herds. Their primary food was seeds and insects stirred up by the great herds. But then we killed the buffalo herds so cowbirds moved east as humans cut down forests to make room for agriculture. Cowbirds can’t live in unlogged forests. The songbird species most susceptible to cowbird shenanigans now are the species that used to live deep in those forests and evolved without cowbirds around. Now their habitat is fragmented and shattered and they haven’t caught on to cowbirds which now have access to all those songbirds’ nests.

No wonder cowbirds like humans, we’ve made life easier for them. True, we killed the buffalo which deprived them of one way of life but gave them another, easier one. Now they have a far larger selection of nests to choose from which gives them even more free time.

__________________________

UPDATE – APRIL 29,2008

Natalie Angier writes about cowbirds in today’s Science section of the New York Times.  You can read it here.


Follow

Get every new post delivered to your Inbox.

Join 58 other followers

%d bloggers like this: