Friday, December 31, 2010

An Early April

After a cold and snowy start to winter, April has made an early appearance in the American Midwest. Strong southerly winds, ahead of the next winter storm, have pumped mild, humid air into the Heartland, priming the region for thunderstorms, which rumbled through Missouri overnight and into this morning.

This brief spring interlude, sporting afternoon highs near 60F and morning lows near 50F, is already beginning to fade; blue skies to the northwest, so inviting from a distance, warn of cold air behind the front. As the storm moves off to the east, northerly winds will push this air into Central Missouri and winter will reclaim the State.

These weather oscillations usually settle down in January as the jet stream assumes a steady, more southern track, keeping us on the cold side of that atmospheric boundary. But the word "usually" is a relative term and North American weather patterns are notoriously fickle. We have reason to hope that April makes several more visits before it finally moves in next spring.

Wednesday, December 29, 2010

Winter & the Elderly

In nature, winter is the culling season. Wild creatures that are old, sick, injured or malnourished often succumb to the harsh conditions; hypothermia, starvation and predation all take a toll. Early man also faced these threats as he emigrated from his tropical home to northern latitudes.

Most older humans will admit that their tolerance to cold weather has decreased with their advancing age and there are physiologic reasons for this perception. As we age our metabolic rate falls, our activity decreases, our calorie intake is reduced and our body fat begins to diminish; all of these factors make it more difficult to retain and generate heat. Furthermore, older persons often have chronic conditions that lead to impaired mobility and balance, making them more prone to falls and injury; the presence of snow and ice only exacerbates this risk. Finally, all of us are more likely to be infected with viruses during the colder months as our indoor lifestyle increases contact with other humans; many of these infections, including influenza, are more severe in the elderly and are more likely to be complicated by pneumonia, sepsis and other potentially fatal conditions.

Sensing all of these factors, older persons with financial resources tend to migrate to warmer climes for the winter months. While longevity is more related to genetics and healthy lifestyle choices, they know that they will be more comfortable in the warm environment. At some deeper level, we may also be experiencing the urge to return to our native ecosystem; we are, after all, a tropical species.

Tuesday, December 28, 2010

Unnoticed Visitors

Novice birders, focusing on common, local, avian residents, often overlook migrants and seasonal visitors that resemble those birds. One such visitor is the purple finch, a fairly common winter resident in California and across the eastern half of the U.S. Since they are similar in appearance to the abundant house finches, their presence may not be appreciated.

A bit larger, stockier and possessing a heavier bill, purple finches are also recognized by distinct plumage characteristics and a notched tail. The males have a rasberry wash over their head, breast and rump, which mixes with brown on their back and is diffused with white on their chest and abdomen; in contrast, the male house finch has an uneven, orange-red coloration, primarily on the head and upper chest. Female purple finches, like female house finches, are streaked with white and brown but have a prominant white facial stripe, just above each eye.

The summer breeding range of purple finches extends across the coniferous forest belt of Canada, down through the northern Midwest, New England, the Pacific Northwest, and southward along the Appalachian and Sierra Nevada mountains. In winter, they abandon the northernmost section of that breeding range and appear in sizable flocks throughout California and the eastern half of the U.S. Maintaining a fondness for coniferous woodlands, they also forage for seeds, buds and berries in mixed woods and weedy fields during the colder months, often turning up at backyard feeders. Like some other winter visitors, such as evening grosbeaks, red-breasted nuthatches and Bohemian waxings, purple finches are erratic wanderers and their numbers vary widely from year to year.

Monday, December 27, 2010

Unaweep Canyon Mystery

While the field of plate tectonics has solved many geologic mysteries, others remain. One of these is Unaweep Canyon in the northern portion of the Uncompahgre Plateau, in western Colorado; unlike other canyons, it has two mouths and a divide along its course, which is now traversed by Colorado Route 141.

Geologists have long debated the natural history of Unaweep Canyon. Some have suggested that, since the canyon is U-shaped, it was carved by mountain glaciers during the Pleistocene; however, closer examination of its floor has revealed that it is a V-shaped, stream-cut canyon, since filled with erosional debris to produce the flattened bed. Others, realizing that the small streams that now flow east and west from the divide could have not produced this magnificent canyon, with its massive walls of hard, Precambrian rock, theorized that the Colorado River originally sculpted Unaweep before changing course to skirt the northern edge of the Plateau.

The most recent evidence suggests that the Gunnison River, which also carved the Black Canyon, once cut through the Uncompahgre Plateau, joining the Dolores River on its west side before flowing northwestward into the Colorado. Based on examination of gravels and other sediments, it appears that the Gunnison gradually sliced through the Uncompahgre ridge as it rose with the rest of the Colorado Plateau during the Miocene-Pliocene Uplift, 25-10 million years ago. A landslide is thought to have disrupted the Gunnison's flow within the Canyon (presumably about 6 million years ago), causing it to back up and eventually flow northward to join the Colorado in the Grand Valley. The abandoned Canyon is now drained by East and West Creeks, too weak to remove the erosional debris of the powerful Gunnison. Time and more field work will tell if this is the true solution to the Unaweep Canyon mystery.

Sunday, December 26, 2010

The Davis Mountains

Looking at a satellite map of the U.S., one notices a dark smudge in West Texas, north of the Big Bend area and just south of I-10. This dark terrain reflects the vegetation and rock formations of the Davis Mountains, which stand out against the pale, drier landscape of the Chihuahuan Desert.

Volcanic in origin, the Davis Mountains are remnants of two large calderas and their associated rhyolite lava flows, ash tuffs, cinder cones and laccolith formations. Persisting for 10 million years, the volcanic activity began in the Oligocene, some 35 million years ago, when grasslands were evolving across the Great Plains and mammalian megafauna dominated the scene. The Davis Mountains cover much of Jeff Davis County and represent the most extensive mountainous region in Texas; summits range from 3500 to almost 8400 feet. Like the Chisos Mountains of Big Bend National Park, the Davis Mountains are part of the Trans-Pecos Volcanic Field, which extends across West Texas and into Northern Mexico.

Catching upslope moisture from all directions, these mountains receive about 18 inches of precipitation each year, more than double that of the surrounding desert. For this reason, they support mixed woodlands of oak, juniper and pine, attracting a large variety of birds, mammals and other wildlife.

Saturday, December 25, 2010

Red-Shouldered Hawks

Though less conspicuous and somewhat smaller than their red-tailed cousins, red-shouldered hawks are fairly common throughout the eastern half of the U.S. and along the coast of California. Identification of this buteo is generally made by the fine, rust-colored barring on its chest, its relatively long, banded tail and its loud, high-pitched, descending call; the red shoulder patches, for which it is named, are not always apparent.

Preferring wooded swamps and riparian forest, red-shouldered hawks usually hunt from a low perch and feed on a wide range of prey, from mice and voles to lizards, frogs, snakes and songbirds. Often considered to be the diurnal counterpart of barred owls, both raptors share the same habitat and both have been threatened by the gradual destruction of forest and wetlands. Ironically, red-shouldered hawks, though often heckled by jays and crows themselves, are known to join these birds when they mob great-horned owls, red-tails and other large raptors.

Like many birds of prey, red-shouldered hawks nest in late winter or early spring; 2-4 eggs are generally laid in a bulky nest, high in a tree, and are incubated by both parents. The young hatch within a month and are usually self-sufficient by summer. While most red-shouldered hawks are nonmigratory, those that nest in northern portions of their range often winter in the southern U.S. or in Mexico.

Friday, December 24, 2010

White Christmas

Caught between high pressure over the Northern Plains and low pressure over the Texas Panhandle, we are getting our Christmas snow here in Missouri. The low is sweeping Gulf moisture in from the south while flow around the high is bringing colder air down from the north; the latter will hang around for several days, assuring us of a White Christmas.

The snow began overnight and has already dropped a few inches of wet snow on the frozen ground; by tomorrow morning, we may have half a foot or more and it will look very much like the Christmas Day that most Americans hope to experience. Snug in our heated homes, we can look out on the winter scene with no sense of alarm and, of course, children will enjoy romping through or sledding over nature's blanket.

Though challenged by the snow cover, wildlife are well equipped to survive its presence; the feeder sites will be especially busy but our winter birds would manage just fine without the handouts. Some mammals will den up until conditions improve while predators may actually benefit from the snowfall, their prey more conspicuous against a background of white. Whether challenged by the storm or not, it is safe to say that wild creatures do not share our sentimental view of a White Christmas; they will carry on with their life-long struggle, surviving one day at a time.

Thursday, December 23, 2010

The Pineapple Express

Produced by an atmospheric trough over the eastern Pacific, the Pineapple Express is a plume of deep, tropical moisture that is swept into the western edge of North America. Developing ahead the the trough's leading cold front and reinforced by circulation around high pressure to the southeast, this flow of warm, humid air, which originates near Hawaii, is forced to rise as it invades the Continent, producing heavy valley rains and dropping copious snow across higher terrain.

In most cases, the plume first strikes the Pacific Northwest; as the trough advances eastward and the angle of its cold front changes, the stream of moisture moves southward, through California and into Mexico. Should the front become stationary, as it did earlier this week, the onshore flow of tropical moisture may continue for several days, producing floods, mud slides, avalanches and great skiing conditions from the Coastal Ranges to the Rockies.

Once the trough moves across the western edge of North America, the Pineapple Express is shut off and cooler, drier air invades from the northwest. While other cold fronts may follow in its wake, they cannot tap the tropical moisture until the original trough moves further eastward and a ridge of high pressure reprimes the atmosphere.

Monday, December 20, 2010

Merry Consumption!

It's the most wonderful time of the year....especially for retailers. Pressured by tradition and expectations, Christians of all kind, from timid secular participants to evangelical zealots, invade the malls, spending lavishly to shower one another with the latest outfits and gadgets. Though bought with loved ones in mind, the gifts also soothe the mind of the purchaser, who must fight the guilt that pervades this season.

While born of a simple story about a charismatic figure who, by all accounts, led a spartan life, Christmas has become a three-month event, focused on extravagant consumption. Some might argue that this annual frenzy, instigated by Big Business and promoted by its army of advertisers, is crucial to the global economy but, in the end, those of us in "developed" countries receive far more than we truly need.

Excess consumption, combined with unbridled population growth, is perhaps the greatest threat to natural ecosystems across our planet. The acquisition of raw materials, the industrial production of consumer goods, the transportation of those products, the trashing of unwanted or used items and secondary pollution at all stages of this cycle degrade the health of our environment. Learning to live with less is the ultimate key to conservation.

Saturday, December 18, 2010

A Morning of Raptors

Venus gleamed brightly in the eastern sky as I drove to our meeting site for the annual Christmas Bird Count. Our group, as usual, was assigned an area south of Columbia that extends from wooded uplands down to the banks of the Missouri; most of this territory is covered by rolling terrain with forested hills, rocky creek channels and valley farms.

The theme for this year's count was set when we heard and spotted two barred owls just before dawn. Clear skies and a minimal wind provided a perfect, if chilly, morning for birding and a large number of species were logged; but this was a morning for raptors. Not long after finding the barred owls, we encountered six bald eagles (5 adults and 1 immature) along the Missouri River, which was nearly covered with floating chunks of ice. As usual, red-tailed hawks were common above and along the farms fields and, today, were matched in number by red-shouldered hawks, which perched in wooded meadows. A sharp-shinned hawk streaked across the road, in pursuit of songbirds, a Cooper's hawk scattered a large flock of cedar waxwings and an American kestrel hunted from a rural powerline. Finally, a seventh bald eagle (another adult) soared above a wetland area, far from the wide Missouri.

Accepting this raptor bonanza to be a hopeful sign, I agreed to trudge up to an abandoned barn to see if it just might harbor a barn owl, an increasingly uncommon species in the American heartland. Alas, the old structure was empty but this morning of raptors will long hold a place in my memory.

Friday, December 17, 2010

The Scent of Skunk

In winter, cold, dry air and frozen ground suppress most of nature's fragrance. One potent exception is the scent of skunk musk, which wafts through the air and is detectable by our relatively poor olfactory system for up to a mile from its source.

Skunks, members of the Mephitidae Family, are represented by at least ten species across the globe, most of which are native to the Americas. Omniverous and crepuscular, skunks roam about to feast on a wide variety of plants, small animals, eggs, garbage and carrion; guided by an excellent sense of smell but hampered by poor eyesight, they represent a large portion of our roadkill. Of course, it is their volatile and irritating musk that wards off many natural predators (great horned owls excluded); produced in perianal glands and found to contain a mix of sulfur-containing thiols, this noxious musk can be accurately ejected for up to 15 feet. Mustelids (weasels, otters, martens, badgers and wolverines) have similar musk glands but, in comparison with skunks, their glands are less developed and their musk is less potent.

Hikers and homeowners have little to fear from these docile creatures; their poor eyesight does not permit planned attacks and they use their musk only in defense. Most often encountered during their mating season in late winter or early spring, skunks spend much of the winter in communal dens, venturing out during periods of relatively mild weather. After mating, females dig their own burrows and give birth to 4-6 kits by May; they will stay with her through the summer, learning to find food and striking fear in potential predators that associate their distinctive coats with foul, irritating showers of musk.

Thursday, December 16, 2010

Great Gray Owls

One of the least conspicuous birds in North America, the great gray owl inhabits the boreal forests of Alaska and Canada and the mountain forests of the Cascades, Northern Sierra Nevada and Northern Rockies; during the winter months, they may also be encountered in Minnesota and northern New England. Preferring dense, coniferous woodlands, they hunt primarily at night but become increasingly crepuscular or diurnal during the colder months of the year; it is then that they are most often observed, perched on a limb that overlooks a forest clearing. While this owl is seldom seen, its deep, resonant hoots often echo through remote northern forests.

Though great grays are our largest owls by length and wingspan (the latter may be up to 5 feet), they are not as heavy as great horned owls; their large head and prominant, ringed facial disc accentuate their size and make their yellow eyes appear to be small and closely spaced. Despite their size, great grays are not overly aggressive and feed primarily on small rodents (mice, voles, hares), grouse and songbirds.

Adult great gray owls have little to fear from natural predators (lynx are among their few adversaries) but their young (born in mid-late spring) may fall victim to goshawks, fishers, wolverines, lynx or bears. Indeed, the adults are more endangered by the activity of man, who drains the bogs and logs the forests that provide refuge to this ghost of the Great Northwoods.

Wednesday, December 15, 2010

Winter Farmlands

Yesterday afternoon, the farmlands east of Columbia presented a bleak winter landscape; snow covered the ground, dead corn stubble and dry, yellow grass quivered in a cold, east wind, dark, barren woodlands shrouded the stream channels and a flat, gray sky diffused and scattered the weak winter sunlight. Were it not for the occasional grove of eastern cedars, one could have painted the scene in black and white.

Amidst this harsh and forbidding environment, one might not expect to see much wildlife but they would be wrong. As expected, raptors dominated the scene; red-tailed hawks surveyed the grasslands from the barren trees, northern harriers skimmed above the cropfields and American kestrels hunted from the powerlines. Skeins of Canada geese moved across the sky, eastern meadowlarks streamed across the roadways and large flocks of blackbirds settled in the fields. Dark-eyed juncos and white-crowned sparrows combed the roadside thickets, eastern bluebirds and mourning doves perched on the fences and northern mockingbirds flashed across the barnyards. Stopping near the woodlots, I observed the usual mix of winter residents (chickadees, woodpeckers, cardinals, blue jays) and, if I had stayed until dusk, there is little doubt that deer, fox and coyotes would have appeared on the snow-covered meadows.

By late afternoon, a band of pink and gold stretched across the western horizon, a sign that tomorrow might be a brighter day. The wildlife, of course, focused on survival, pay no heed to such signs of hope; driven by instinct, they live in the present and have no inclination or ability to anticipate the future. Indeed, in the fickle world of nature, tomorrow is never assured.

Tuesday, December 14, 2010

Mourning Dove Sit-In

Faced with snow-covered ground and an invasion of Arctic air, mourning doves have gathered in our large magnolia over the past two days; since this tree is on the south side of our house, it is protected from the cold north wind and receives plenty of sun, even in the winter.

Like many bird species, mourning doves form large, sociable flocks during the colder months but, unlike the others, these mellow birds assemble with little fanfare. Were it not for their distinctive forms, huddled in groups on the bare branches, one could easily overlook them. Content to watch their high strung neighbors as they squabble over the nearby feeder, the doves sit patiently, basking in the sun and waiting to partake of seed that falls to the ground. If not spooked by a sharp-shinned hawk, they may sit there all afternoon, heads on chests, oblivious to the winter chill.

Their peaceful sit-ins are a welcome sight during this trying season; the tranquility is infectious and their calm, polite demeanor is especially reassuring in the midst of our holiday frenzy. The doves remind us to stop and enjoy the moment; life is too short to be rushing through its fickle course.

Monday, December 13, 2010

Night of the Geminids

While not as famous as the Perseids of August or the Leonids of November, the Geminid meteors of December offer the most reliable display of the year. Produced by debris from the 3200 Phaethon asteroid, discovered in 1983, the Geminid meteors were first observed by a British astronomer in 1862, making them the youngest of the annual meteor showers; indeed, most of the other major displays, produced by debris from comets, have been documented for thousands of years (and have likely occurred much longer than that).

The Geminid debris field is the largest that Earth encounters in its annual journey around the sun. Up to 160 meteors may be seen in the course of an hour, seeming to radiate from the Gemini constellation; since they are relatively slow moving (compared to meteors in other displays) and since they tend to leave a vapor trail, the Geminids are also the easiest to observe.

Occurring from December 6 to December 19, the Geminid meteor show peaks on the nights of the 13th and 14th; as with all meteor displays, they are best observed on clear, moonless nights, away from the glow of city lights. Fortunately, astronomers project that the Geminid display will intensify over the coming years as Earth's orbit more directly intersects the path of the parent asteroid.

Sunday, December 12, 2010

Backside Blizzard

In the Northern Hemisphere, as storm systems track from west to east, the winds around their center of low pressure move counterclockwise. Ahead of the storm, southerly winds pump warm, humid air into the system, triggering showers and thunderstorms as the cold front approaches. North of the storm's center, this moisture is pulled into cold air behind the front, producing cool rain or snow, depending on the temperature of that air. If the storm is especially strong, determined by the depth of its central pressure, the circulating winds can be fierce and, when combined with snowfall, may produce blizzard conditions on the north and west sides of the system.

The current winter storm, centered over Lake Michigan this morning, is very potent. Its vanguard of showers and mild air flowed across Missouri on Friday, extending into Saturday morning; by Saturday afternoon, cold air was filtering in from the north and, by last evening, snow showers mixed with a gusty northwest wind. The strong winds and snowfall increased through the night, producing blizzards of horizontal snow and pulsations of wind that roared through the barren trees. By morning, we had 4 inches of fresh powder, blown clear in some areas and piled into deeper drifts in others.

It is now almost noon; the storm has moved to the east, the winds have died down and a snowy landscape reflects a bright southern sun; the temperature sits at 18 degrees F. Travel will be slow and shoveling will be necessary but we have survived another round of nature's fury.

Friday, December 10, 2010

Cheshire Moon

Stepping onto the deck last evening, I caught sight of the crescent moon, turned on its back in the western sky. Catching the orange glow of the setting sun and looming just above a branch of our neighbor's tree, it evoked the grin of the Cheshire Cat, Alice's friend and nemesis.

Both enamored with and frightened by the winter night, humans, like Alice in Wonderland, have long confronted its mysteries and threats. Natives of the Tropics, we are poorly equipped to survive the harsh conditions of winter and, devoid of night vision, we remain at the mercy of creatures that patrol its darkness. And the night sky, with its fabulous cast of glowing objects, has long inspired and threatened man, prompting us to imagine figures and omens in its pattern of moving lights.

As the Cheshire Moon dropped toward the horizon, I turned my attention to bright Jupiter, high in the southern sky, and to the other constellations that adorn our winter nights. Despite our advanced scientific knowledge, we have only begun to understand the worlds beyond our own. One day, if we do not destroy our own civilization first, we will step through the looking glass to explore the rest of our Universe.

Tuesday, December 7, 2010

Life, Dinosaurs & Time

Life first appeared in Earth's primordial seas some 3.6 billion years ago and evolved into a wide diversity of marine and terrestrial creatures before dinosaurs arose. Unicellular organisms, echinoderms, mollusks, insects, arachnids, crustaceans, fish, sharks, mosses, ferns, conifers, amphibians and many reptiles appeared before the dinosaurs and continue to evolve today.

Dinosaurs ruled our planet throughout the Mesozoic, which stretched from 225 to 65 million years ago (MYA), but other life forms also arose during that Era. Turtles, crocodilians and the earliest mammals appeared in the Triassic Period (225-190 MYA), ancestral birds and flowering plants graced the Jurassic Period (190-135 MYA) and the Cretaceous Period (135-65 MYA) witnessed the rise of ants, social bees, snakes, marsupials and the first deciduous trees.

Since the end of the Mesozoic (65 MYA), when dinosaurs became extinct, these "terrible lizards" live on as birds and Earth's mammals have exploded in number and variety. Primates, bats, cetaceans, manatees, rodents, canids, felines, ruminants, horses and essentially all of our modern mammals arose after the Age of Dinosaurs. Hominids have walked the Earth for no more than 6 million years and the human species is less than 150,000 years old.

Monday, December 6, 2010

Eastern White Pines

It is during the winter, when the deciduous trees are bare, that we pay most attention to the conifers. But, since I park by pickup beneath a large white pine at our Columbia home, I find it hard to ignore this tree in any season. In spring, its small staminate flowers release a copious amount of yellow pollen which coats the truck; soon thereafter the spongy flowers begin to fall, collecting in the bed or along the base of the windshield. Drops of pine sap leave sticky residue on the hood throughout the year and heaps of yellowing pine needles surround the pickup in mid autumn.

Eastern white pines, the largest conifers in eastern North America, are native to southern Canada, New England, Pennsylvania, and the Great Lake States, extending southward along the Appalachian chain. Widely planted as ornamentals, these stately trees were once used for sail masts and are now harvested for lumber or used as Christmas trees. Often growing up to 100 feet tall and possessing a girth that may exceed 10-15 feet, some white pines in virgin stands exceed 200 feet in height. Those that escape browsing, disease or human harvesting may live for 250 years and a few specimens are known to be nearly 500 years old.

Due to their relatively long needles (bundled in groups of 5) and the open spacing of their limbs, eastern white pines have an airy appearance. Their 6-inch cones peak in number every 3-5 years and bear seeds that are favored by tree squirrels, pine siskins, nuthatches, crossbills and a variety of finches. Moderately resistant to fire, white pines often form extensive stands in undisturbed areas, overgrowing and shading out their smaller deciduous neighbors. My pickup truck and I can certainly vouch for their rapid growth and prolific nature!

Sunday, December 5, 2010

Evolution of the Sonoran Desert

The Sonoran Desert of the Southwest U.S. and Northwest Mexico is a product of its latitude, the global climate and the regional topography. Lying along one of the desert bands (which run just north and just south of the Tropics), this arid ecosystem receives copious sunshine and is subjected to prolonged periods of high pressure, below which the air is sinking. This atmospheric condition retards cloud formation and both warms and dries the air as it plummets toward the Earth's surface.

Covering a broad basin and surrounded by highlands, the Sonoran Desert is shielded from moisture in all directions; to the northwest are the Sierra Nevada Mountains and the high Mojave Desert, to the north and east is the Mogollon Rim of the Colorado Plateau, to the southeast is the wall of the Sierra Madre Range and, to the southwest, are the mountains of Southern California and the Baja Peninsula. Any air that enters the Sonoran is thus downsloping from higher terrain, causing it to heat up and dry out even further. Since the mountains and plateaus that surround it were uplifted within the past 4 to 20 million years (during the Miocene and Pliocene), the Sonoran Desert is one of the youngest ecosystems on our planet.

Throughout the Pleistocene and into the Holocene, Earth's climate has undergone dramatic shifts. When the climate cooled and glaciers advanced, the area of the Sonoran Desert decreased; in contrast, when the climate warmed (as it has done over the past 10,000 years), the Desert advanced, climbing onto the walls of the adjacent highlands. Throughout these gyrations, the regional flora and fauna have evolved, developing traits that enhanced survival in an arid environment with intense sunshine, cool nights and seasonal rains.

Saturday, December 4, 2010

Madagascar and its Primates

As Pangea continued to break apart, Madagascar split from Africa, some 160 million years ago. Drifting to the south, it merged with the remnants of Gondwanaland, the combined mass of Antarctica, India and Australia. There, its African flora and fauna mingled with the plants and animals of that tropical land mass. About 95 million years ago, the India-Madagascar segment broke from Antarctica-Australia, moving to the northeast; within another 15 million years, Madagascar began to rift from India, presumably triggered by an underlying hotspot that also produced the massive Deccan Traps basalt flow at the end of the Mesozoic. By 70 million years ago, Madagascar was moving into prolonged isolation and now rests 350 miles off the southeast coast of Africa.

While the earliest mammals arose during the Triassic, more than 200 million years ago, primates first appeared late in the Cretaceous, after Madagascar had become an isolated land mass. About 60 million years ago, these ancestral primates split into the prosimian line (which led to lemurs, lorises, galagos and pottos) and the anthrapoid line (leading to monkeys, apes and hominids). Spreading across the globe these two groups shared similar habitats and, over time, the anthrapoids were more successful, pushing the prosimians toward extinction.

According to current scientific theory, ancestral lemurs reached Madagascar on rafts of vegetation, torn from the African coast by seasonal storms. There, free from anthrapoid competition, they have flourished and, today, are represented by more than 100 species and subspecies. A second primate, humans, reached Madagascar by boat, colonizing the Earth's fourth largest island about 2000 years ago. Unfortunately, the Malagasy and their descendents have since destroyed much of the natural habitat; lemurs and other Madagascar animals, 80% of which are endemic to the island, are increasingly threatened by deforestation and other human activity.

Friday, December 3, 2010

The Voice of Winter

Winter is the quiet season. Compared with the rest of the year, there are relatively few natural sounds that greet us on our excursions through the fields and woodlands. Of course, exceptions do exist: the crunch of snow beneath our boots, the rattling of limbs in the winter wind, the rustling of dead oak leaves and the dreaded sound of sleet, coating our cars and walkways. The wild creatures chime in now and then: the howl of coyotes, the eerie bark of fox, the cheerful tune of chickadees, the drumming of woodpeckers and the raucous cries of jays and crows come to mind. But, for me, the voice of winter is the gruff call of the great horned owl.

Oblivious to the ice, snow and frigid air and well equipped to stalk the long, dark nights, this large and powerful predator symbolizes the harsh winter season and epitomizes the survival skills that it demands. Hidden from view for much of the day, great horned owls appear along wood borders in the gathering dusk, ready for a night of hunting. They have a distinct advantage during the barren months of winter, ensuring good health for their breeding season, which will commence by January.

Ominous to many, their deep, echoing hoots inspire those of us who appreciate the hardiness and stamina of our wild winter residents. It is understandable that mice, cottontails and other small mammals may not share that appreciation.

Thursday, December 2, 2010

The Benefits of Aging

Aging has its disadvantages. Our physical strength and stamina tend to deteriorate, we are more prone to a variety of illnesses and, for some, our mental faculties begin to fail. When we reach middle age, we begin to notice the early signs of aging and, combined with the other stressors of that period, this observation can induce a sense of resignation and cause some to give up on the joys of life.

But those who remain active, both physically and mentally, come to realize that there are also benefits of growing older. For most of us, the responsibilities of our career and our family life begin to disipate and we have more time to engage in exercise, hobbies and other personal interests. Those endowed with creativity are especially rewarded by this age-induced freedom; indeed, history is replete with famous writers, painters, photographers and other artisans who took up their passion later in life and, possessing the experience and wisdom of advanced age, were especially productive and successful.

Whether or not you possess such talents, the decision to engage in new activities will likely benefit your physical and mental health. The process of learning a new skill exercises the brain and the body, enhancing mental function, improving coordination and inducing a sense of personal satisfaction, all of which make us less prone to illness and injury. Death is surely inevitable but growing old can have its rewards.

Wednesday, December 1, 2010


A northwest wind developed yesterday afternoon, behind the latest cold front, and, overnight, ushered in the coldest air and lowest wind chill since last winter. December made its appearance beneath a frigid, clear sky, lit by a crescent moon, bright Venus and a bowl of twinkling stars. On my walk to work this morning, it was 22 degrees F.

Festooned with holiday lights and leading up to the beloved season of Christmas, December does not incite the animosity that January and February stir in the soul of tropical man. Nevertheless, in the Northern Hemisphere, December is the darkest month of the year and often brings severe winter weather. Even when relatively mild, the month heralds the long, steady descent toward the nadir of nature's year.

December 1 marks the calendar and meteorologic onset of winter which, from an astronomical point of view, begins with the winter solstice, on or about December 21. One can debate when the season officially begins but, to paraphrase a Supreme Court Justice, "we know it when we feel it" and, today, it felt like winter.

Sunday, November 28, 2010

South of Town

North of Columbia, the landscape soon gives way to the relatively flat terrain of the Glacial Plain that covers much of the Midwest, from central Ohio to the eastern Dakotas. But south of town, one encounters the rolling hills, bluffs and floodplain of the Missouri River Valley; it is a landscape of wooded slopes, hilltop meadows and valley farms, all sloping toward a broad, flat swath of cropfields, wetlands, bottomland woods and the River itself.

On this bright, cloudless morning, I journeyed through this landscape, winding along graveled roads and stopping now and then to observe the changing scenery. Mourning doves and eastern bluebirds huddled on the powerlines, blue jays, mockingbirds and cardinals flashed across the roadways and mixed flocks of juncos and winter sparrows scattered from the roadside thickets. Red-tailed hawks circled above the frosted fields and an occasional red-shouldered hawk patrolled from a barren tree. Though common in this habitat, wild turkeys had not yet left their forest retreats, leaving the meadows and corn stubble to herds of livestock and flocks of Canada geese.

Down on the floodplain, noisy killdeer raced along the mudflats, crows foraged in the crop fields and a lone bald eagle surveyed the scene from a riverside grove. A steady south wind negated my opportunity to observe migrant snow geese but distant, high clouds, off to the northwest, foretold of an approaching storm. That front, due tomorrow, will reinforce the winter season and another wave of snow geese will ride its northerly wind across the Heartland.

Friday, November 26, 2010

Swans over the South Platte

Not inclined to join the mob scene at area malls and presented with another mild, sunny morning along the Front Range, my wife and I decided to take a hike along the South Platte River. A series of cold nights have coated many of the smaller ponds with a sheet of ice and wintering waterfowl are now congregating along the river and its adjacent lakes.

Joining the permanent residents (mallards, gadwalls, Canada geese, wood ducks, northern shovelers, American wigeon and common mergansers) were an excellent variety of winter residents and visitors; these included buffleheads, common goldeneyes, American coot, hooded mergansers, lesser scaup, green-winged teal and ring-necked ducks. On our walk through the South Platte Valley we also encountered belted kingfishers, northern flickers, red-tailed hawks, a lone rough-legged hawk, black-billed magpies, great blue herons, ring-billed gulls, song sparrows, red-winged blackbirds and an industrious muskrat.

But the highlight of this November morning was a flock of tundra swans, winging their way toward Chatfield Reservoir. All eight were in full adult plumage and were unusually silent on their graceful flight above the South Platte. After breeding on the Arctic tundra of Alaska and northern Canada, most tundra swans winter on estuaries along the mid Atlantic and Pacific Coasts; smaller numbers migrate through the interior, heading for the marshlands of New Mexico and Texas.

Thursday, November 25, 2010

A Global Thanksgiving

On this American holiday of Thanksgiving, most of us will give thanks for our human possessions and relationships. But our lives, our health and our society are dependent upon the background support of Earth's natural ecosystems.

Those who do focus on the benefits of nature are likely to mention spectacular sunsets, beautiful scenery, wondrous night skies and the inspiration of our magnificent diversity of wildlife. In referring to the latter, there will be reference to eagles, whales, wild horses and other creatures that humans hold in high esteem. Few will give thanks for fungi or beetles or earthworms, yet, their presence and activity is as vital to our welfare as any other life forms that share this planet.

Indeed, all life on Earth is interdependent. Diverse human cultures, while prone to disagreement and conflict, must learn to cooperate if our species is to survive. And we humans, inclined toward self importance, could not survive without the support of our planet's "lowest" plants and animals. It is thus appropriate that we give thanks for life itself, in whatever form it may exist, and dedicate ourselves to its protection and conservation.

Wednesday, November 24, 2010

The Colorado Piedmont

When the Rocky Mountains first crumpled skyward, 70 million years ago, the adjacent plains rose with them, producing a gradual rise from the High Plains to the eastern flank of the central uplift. Streams meandered eastward from the modest summits which were gradually eroded to the level of the sloping plain. A second uplift of what is now the Colorado Plateau and Rocky Mountain corridor began about 25 million years ago, significantly augmenting the elevation of the mountains and increasing the erosive power of the streams that flowed from the high country.

These streams and subsequent Pleistocene glaciers sculpted the mountains and foothills, removing overlying sediments and cutting numerous canyons through the ancient, Precambrian core. Rumbling onto the plains, the streams merged to form two primary channels, the South Platte and the Arkansas Rivers, their watersheds split by the Palmer Divide; this high, broad ridge, which rises between Denver and Colorado Springs, still connects the High Plains with the east edge of the Front Range. The Rivers and their numerous tributaries have molded a scenic terrain of valleys, low ridges, mesas and hidden canyons along the base of the Rockies, extending eastward along the channels of the primary streams; lower than the adjacent mountains and High Plains, this landscape is known as the Colorado Piedmont.

The great majority of Coloradans live on the Piedmont and its valleys of Cretaceous Pierre Shale support a large portion of the State's agricultural production. The numerous lakes and reservoirs of the Piedmont attract bald eagles and migrant waterfowl while the wooded streams and canyons host the greatest concentrations of eastern Colorado wildlife. Basking in the rain shadow of the Rockies, the human and wild residents of Colorado's Piedmont enjoy a spectacular climate while dodging most of the severe thunderstorms and blizzards that plague the High Plains.

Tuesday, November 23, 2010

Canadian Sunsets

As the sun sets behind the Colorado Front Range, lines and Vs of Canada geese take to the skies. Common across the urban corridor throughout the year, these large waterfowl are especially abundant from November to March, when the permanent residents are joined by their migrant cousins.

After feasting on natural grasslands, golf courses and the manicured lawns of parks and cemeteries throughout the day, the geese return to our lakes and reservoirs to spend the night. There, surrounded by water or ice, they are protected from the coyotes, fox and feral dogs that prowl the Piedmont; unless taken by surprise, Canada geese are large and aggressive enough to protect themselves from these predators.

Having lost favor due to their abundance and their habit of fouling our pristine lawns, Canada geese do not inspire the average citizen (or even the average birder); but one must admire their tenacity, their cooperative instincts and their powerful flight. Backed by the Rockies and the spectacular Front Range sunsets, their wildness and beauty are easy to appreciate.

Monday, November 22, 2010

Snows in the Clouds

Heading to Colorado for the Thanksgiving Holiday, we left Columbia shrouded in moist, balmy air, courtesy of a stiff southerly wind; the latter was produced by an advancing cold front, still in Kansas at the time of our departure. Once we reached Kansas City, the location of the front was obvious as low, gray clouds formed a dense wall across the western horizon.

Passing through the front, the temperature dropped from the sixties to the forties and the wind shifted from the south to the northwest. Layered cloud decks replaced the blue sky and sunshine of our Missouri leg and it looked like our trip across the Great Plains would be far from appealing. Then, in Central Kansas, flocks of snow geese appeared amidst the clouds and my concern about the weather was soon forgotten.

Catching a ride on the strong, northwest winds, these vocal migrants were surely on their way to the Gulf marshes of the Texas Coast. They will probably make another stop in the Arkansas or Red River Valley before pushing on to their wintering grounds and we were fortunate to observe a small segment of their journey from the Arctic. The encounter may have been relatively brief, but the memory will invoke wanderlust in my soul for years to come.

Sunday, November 21, 2010

Marriage: an Unnatural Union

Marriage is not a natural human relationship. Rather, our society has collectively decided (and most of us would agree) that children are best reared in the setting of a monogamous commitment. Unfortunately, our natural traits tend to undermine and disrupt these good intentions.

The romantic, "can't get enough of each other" phase of marriage is often fleeting and, in some cases, is over before the vows are exchanged. It is followed by the "what have I done?" phase, when we begin to pay more attention to annoying traits of our partner and come to resent our loss of independence. The arrival of children usually rescues the marriage, as parental pride and the shared responsibilities of nurturing our kids rekindle the romance. Once they are teens or young adults, however, other threats emerge, including discipline issues, Oedipal jealousies and nostalgic yearnings for the freedom that our progeny enjoy.

Perhaps the greatest threat to the stability of marriage occurs when the children are finally independent, often coinciding with the boredom of our middle age lives. Men, naturally attracted to fertile females, have a tendency to stray while many women, having sacrificed careers for their children and now facing entrenched societal discrimination, come to resent the advantage that their spouse has enjoyed; if not rescued by communication, compromise and the trust to extend individual freedoms, the relationship often disintegrates. Those couples who make it through this stage have generally learned to respect the human need for personal space and, if luck holds, they finish out their lives together.

Saturday, November 20, 2010

Winter's Assault

As of this morning, a potent winter storm was spinning over the Great Basin and its associated cold front stretched from San Francisco to Maine. Pulling in moisture from the Pacific Ocean, the storm is expected to drop heavy snow from the Sierra Nevada to the Rocky Mountains.

North of the front, frigid air is pouring into Montana and the Dakotas, the vanguard of winter's sweep through the country. Here in Missouri, the temperature will push into the sixties over the next few days, as southerly winds develop ahead of the front; by Tuesday, winter should arrive.

Summer's feeble jabs are weakening and, like a light-weight contender facing the heavy-weight champion, it is at risk of a knock-out blow. Winter is gaining strength with each shortening day and its grip will tighten as summer retreats to the south. For all practical purposes, the battle has been won.

Thursday, November 18, 2010

Ringing in the Season

On this first cold evening of the season, I was surrounded by the tinkling song of juncos as I walked home in the fading twilight of dusk. Down from the great Northwoods, these small, attractive songbirds are a fixture of the Midwest winter, thrilled to spend the cold, dark months in our relatively balmy climate.

Feasting on weed seeds, they scavenge our brushy fields and woodlots, scattering into shrubs and thickets if danger is sensed; as they do, their white outer tail feathers unveil their identity. Dark-eyed juncos are hardy survivors, christened "snow birds" for their seeming indifference to the challenges of winter weather.

Those who place feeders in the yard can observe these birds at close range; both slate-colored and Oregon races visit the Heartland. Unlike many of our residential songbirds, they shun the feeder perches, preferring to search for seed that has fallen to the ground. We'll enjoy their company until early April, when the weather gets too warm for their taste; it is then they'll escape to their homeland, the vast coniferous forests of Canada.

Wednesday, November 17, 2010

Autumn Rain

Unlike recent cold fronts, our current trough has tapped a fetch of Gulf moisture and cold rain is falling across central Missouri. Though the rain will be short-lived and modest in quantity, it has temporarily doused our image of a crisp and sunny Midwest autumn.

Such bands of rainfall, caused by the same atmospheric clash that brings early spring showers, are more common in autumn than we care to admit. An unruly jet stream characterizes both seasons, mixing chilly air from the north with a warm, moist flow from the south. The result, raw days with cold rain and shifting winds, is perhaps the least favored weather of nature's year.

While spring showers are often welcomed, ushering in the season of growth and renewal, autumn rains are recognized as the vanguard of a deeper chill. The wet leaves and muddy fields that they leave behind offer little promise of brighter and warmer days ahead. Rather, these autumn rains lead toward the dark, cold realm of winter where, in time, they will convert to a seasonal mix of sleet and snow.

Monday, November 15, 2010

Exorcism 2010

Born of fear and scientific ignorance, religions have retained significant influence thoughout the course of human history. Early man, facing the many threats of prehistoric life, developed beliefs and rituals which, over time, have morphed into the religions that we know today. Ingrained in childhood, reinforced by clergy, imposed by governments and maintained by social pressures, they continue to govern our lives.

Modern man tends to ridicule the "pagan" rituals of prehistoric "savages" while defending the mysticism that still pervades our culture. This week, Catholic bishops are convening in Baltimore to review and update the Church dogma related to exorcism, the ritualistic treatment of persons who are "possessed by demons." Despite the advances and revelations of modern neuroscience, the bishops cannot relinquish their conviction that mental illness may be induced by evil spirits!

While some are amused by this exorcism conference, many of us see it as another sign that the talons of religious indoctrination still grip human society. We are embarrassed for our species and view Exorcism 2010 as an insult to human intelligence.

Sunday, November 14, 2010

Red-tail Highway

Red-tailed hawks are common on the farmlands of the Midwest and are especially conspicuous during the colder months of the year. It is then that they congregate along our country roads and Interstate highways, hunting for small rodents that inhabit the grassy medians and berms.

On my travels to and from Ohio this weekend, the red-tails were abundant, perched on fenceposts, tree limbs or power poles if not soaring high overhead or rising from the grass with a victim in their talons. Their bulky frame is easy to spot in the barren woodlands and their pale, red tail feathers aid identification as they flap and glide above the fields. Though outnumbered by starlings and (perhaps) turkey vultures, these buteos are readily observed by anyone who traverses the open country of America's Heartland.

Indeed, when scouting birds for the annual Audubon counts, one often hears the retort that "it's just another red-tail." But their common occurrence does not detract from the power and grace of these magnificent raptors and should not minimize their role in controlling the rodents and cottontails that might otherwise decimate our vital croplands.

Wednesday, November 10, 2010

A Polarized Nation

As if our political polarization was not bad enough, the jet stream has now divided our country. This afternoon, a broad dip in the jet has brought winter conditions to the western U.S. while the eastern half, protected by a dome of high pressure, basks in summertime warmth. The dividing line between the trough and ridge runs north to south across the Central Plains; on either side of this cold front the temperature varies by 20 degrees F.

Such potent contrasts set the stage for severe weather and, once the trough moves into areas primed with Gulf moisture, thunderstorms will ignite. Meanwhile, within the trough, an upper level low is spinning from the northwest to the southeast, producing mountain snows and bringing the first significant upslope snow to Front Range cities.

Over the next few days, the protective dome will shift eastward, summer will retreat and a taste of winter will invade the Heartland. Here in Missouri, we'll escape the western snow but chilly rain and blustery weather will deliver a reality check; it is, after all, November.

Tuesday, November 9, 2010

Jurassic Parks

The Colorado Plateau of the Western U.S. harbors one of the most extensive exposures of Jurassic strata on our planet. Stretching from 200 to 135 million years ago, the Jurassic Period covered the heart of the Mesozoic Era, the Age of Dinosaurs.

A number of our National Parks and Monuments are famous for their Jurassic deposits and, by extension, their cargo of dinosaur fossils. Dinosaur National Monument, in northwest Colorado and northeast Utah, is a showcase for the Morrison Formation; deposited in a long, shallow basin, from Canada to New Mexico, this layer cake of mudstones, siltstones, coal and sandstone is famous for its late Jurassic fossils. A bit older, the Entrada Sandstone, deposited in the mid Jurassic, is highlighted at Arches National Park, in eastern Utah, where it has been sculpted into a spectacular array of fins, natural bridges and arch formations.

Perhaps most famous of the Jurassic sedimentary rocks is the Navajo Sandstone, deposited about 190 million years ago when a vast desert covered the region. Relatively soft and heavily jointed, this sandstone forms the upper cliffs of Canyonlands National Park, the scenic domes of Capitol Reef National Park and the towering walls of Glen Canyon, now drowned by Lake Powell. Separated from the Navajo Sandstone by the Kayenta Formation, the Wingate Sandstone yields the middle cliffs of Canyonlands and the majestic, sheer walls of Colorado National Monument; though officially dated from the onset of the Jurassic, some geologists argue that, based on its fossil contents, the Wingate was deposited near the end of the Triassic.

Monday, November 8, 2010

Summer takes a Round

After a week of frosty mornings and the sense that winter was taking control, summer got off the mat and reclaimed mid Missouri today. Its victory may be brief but we'll enjoy a few days in the seventies before the next cold front pushes through the Heartland.

Any thought of raw, gray, November weather has vanished, as coeds stroll across campus in shorts and t-shirts. A steady, southerly wind has the flags rippling atop the ROTC building and has coaxed a trio of vultures into the air. If not for the long shadows and the fading colors of autumn, one might think it was early September.

Such gyrations in our Midwest weather are typical of autumn as a restless jet stream undulates across the country. While songbirds, attuned to the light cycle, are not fooled, the waterfowl will slow their migration until heavy snows and frozen ponds drive them south. As much as I look forward to those wavering flocks of snow geese, this mild interlude is a welcome setback. After all, in due course, winter will win the battle.

Sunday, November 7, 2010

The Great Oceanic Plates

When Earth's Continents merged into Pangea, some 250 million years ago, the vast intervening ocean stretched across two oceanic plates, the Pacific and the Farallon; spreading out from a mid-oceanic ridge, the Pacific Plate lied beneath the western half of the sea while the Farallon occupied the eastern half, abutting the future Americas.

Pangea began to break up during the Triassic, as the Tethys Sea opened from east to west. Later, in the Jurassic, the Atlantic began to open, shoving the American Plates to the west. As this occurred (and continues to occur), the Farallon Plate was forced to subduct beneath the American Plates and, in doing so, added a cargo of sub-continents to western North America, crumpled up the Rockies and created a broken chain of subduction volcanoes from the Andes to southeast Alaska. Today, only remnants of the Farallon persist, including the Nazca Plate along the west coast of South America, the Cocos Plate west of Central America and the Juan de Fuca Plate (and a few smaller remnant plates) off the west coast of the Pacific Northwest.

The Pacific Plate, devoid of major continental masses continues to form along its ridge with the remnants of the Farallon and along its younger ridge with the Antarctic Plate. Inching to the northwest, the Pacific Plate scrapes through Southern California along the San Andreas Fault and eventually subducts beneath or overruns the North American, Eurasian, Philippine and Australian Plates in a broad arc, from the Aleutians to New Zealand. For now, only hotspot volcanic islands disrupt its vast expanse of open sea; eventually, this great oceanic plate will also disappear as new oceans open, our current continents rift apart and the Pacific subducts into history. Just like the Farallon and its many other predecessors, the Pacific Plate is a transient feature of Planet Earth.

Saturday, November 6, 2010

Morning Chill at Eagle Bluffs

Arriving at Eagle Bluffs Conservation Area this morning, it was clear that winter had taken charge of the refuge. Flocks of horned larks and meadowlarks moved across the frosted fields while smaller groups of crows foraged amidst the brown corn stubble. Kestrels surveyed the scene from roadside powerlines and red-tailed hawks soared overhead, scouting for mice or cottontails on the cold, yellowing grasslands.

As expected, most of the preserve is closed for duck hunting but there were a fair variety of waterfowl on accessible lakes and waterways. Mallards and wood ducks cruised through the flooded timber while shovelers, gadwall and coot gathered in the shallows; pied-billed grebes were especially common, diving amidst the reeds and aquatic vegetation that rimmed the ponds.

This placid scene was disturbed only by the shotgun blasts that rang through the valley. Watching the ducks in the safe zone, one wanted to warn them of danger just to the south; they, of course, were oblivious to the threat and showed no response to the distant explosions. It was, in some ways, a disturbing experience, watching these potential victims that, later in the morning, might venture across the killing fields.

Friday, November 5, 2010

Claron Lake

When the Rocky Mountain chain began to rise, some 70 million years ago, the crust to its west was stretched, producing a mosaic of ridges and broad basins. Drainage into the basins created large inland lakes, including the Green River Lakes of the Utah-Colorado-Wyoming Tristate and Claron Lake of southwest Utah. All of these lakes gradually filled with sediments of the Paleocene and Eocene Periods (60-50 million years ago); the deposits in the Green River Lakes would eventually yield the famous oil-shales of the Roan Plateau while deposits in Claron Lake would become prized more for their natural beauty.

Compacting into layers of limestone, dolomite, siltstone and conglomerates and capped by volcanic tuff from the Oligocene Period (30 million years ago), the Claron Formation was lifted with the rest of the Colorado Plateau during the Miocene-Pliocene Uplift, some 25-10 million years ago. Erosion and faulting would eventually expose the Claron beds along the edge of regional plateaus; Cedar Breaks National Monument, a spectacular natural amphitheater on the west edge of the Markagunt Plateau and Bryce Canyon National Park, on the east edge of the Paunsaugunt Plateau, protect the most scenic exposures.

Rich in iron oxides and manganese oxides, the colorful limestones and dolomites have eroded into striking rock formations, known as hoodoos. These pinnacles, capped by more resistant rock layers have been split apart by stream erosion and freeze-thaw fracturing. Once lying beneath an ancient lake, they now gleam in the bright Utah sun and adorn calendars across the globe.

Thursday, November 4, 2010

Tardy Canadians

Perhaps our balmy October weather kept them at bay. Or perhaps they arrived under the radar and I've been too busy to notice their presence. For whatever reason, I saw the first white-throated sparrows under our feeder this afternoon, a sign that they have escaped the harsh winter of Canada to spend the dark season in the mild confines of central Missouri.

Two weeks behind schedule, their appearance is always a welcome sight and their plaintive song will brighten the long, dreary months of winter. That tune will build in urgency during the waxing days of early spring and, by mid April, they'll depart for their homeland, never to endure the sticky weather of a Midwest summer.

Watching them beneath the feeder, one wonders if they would stay put if they knew about the mild conditions along the Gulf Coast. If informed, would they pull up stakes and head for the sandy pinelands of that southern clime? I tend to doubt it; after all, these hardy birds have adapted to the cool climate of the Great Northwoods and our Missouri winters, however taxing, pose little threat to their survival. On the other hand, a few months in the heat and humidity of the Gulf Coast, while inviting to many humans, might sap their energy and hasten their demise. I, for one, would never encourage them to leave; their stoic presence, especially on those frigid winter mornings, is an inspiration to all of us who cannot escape.

Wednesday, November 3, 2010

The Nature of Politics

The elections are over. The Republicans control the House, the Democrats will likely retain the Senate and, in the end, nothing will change. At least the obnoxious commercials and recorded phone messages will stop for a while.

American politics is all about power, celebrity and perks. During campaigns, the candidates parade their families before the camera, visit local merchants, extol the values of middle America and promise to restore our faith in Government. Once elected, it's politics as usual: pompous rhetoric, cable TV appearances, travel junkets, celebrity galas, golf tournaments, extra-marital affairs and deal-making legislation to ensure that constituents get what they want. After all, their primary goal is to be re-elected. Meanwhile, wars drag on, the economy stagnates, the wealth gap widens, individual rights are threatened and a commitment to environmental protection is but an empty promise.

The concept of term limits surfaces now and then and, in my opinion, deserves serious consideration. Professional politicians argue that they understand the logistics of government and that a regular turnover of Congress would diminish their effectiveness. The evidence, however, suggests otherwise.

Tuesday, November 2, 2010

The Heart of Volcanism

The great majority of Earth's volcanoes are found along subduction zones, where one tectonic plate is dipping beneath another; the lower plate begins to melt as it approaches the mantle, magma rises and a chain of volcanoes develops near the edge of the overriding plate. The famous Ring of Fire refers to the numerous subduction zone volcanoes that have developed along the Pacific Rim; these include the Andes, the volcanoes of Central America, the Cascades, the Aleutian Islands, Japan, Taiwan and the Philippines, among others.

But the most concentrated and active swath of subduction volcanoes lies along the western and southern edge of Indonesia, where the Australian Plate is subducting beneath the Eurasian Plate. Having developed within the past 15 million years, the volcanic islands of Sumatra, Java, Bali and others harbor more than 150 active volcanoes and have been the site of some of the most powerful volcanic eruptions in Earth's history: Krakatoa, Toba and Tambora. Over the past week, Merapi, on Java, has begun erupting for the 27th time since 1930, the most active and, in light of the regional population, one of the more deadly volcanoes on our planet.

This concentration of volcanism in Indonesia is, of course, merely a reflection of Earth's current geography and topography. Since it formed, 4.6 billion years ago, our planet's surface has undergone constant change; oceans have opened and closed, continents have merged and rifted apart and the sites of active subduction have shifted across the globe. The intense volcanism in Indonesia and elsewhere is evidence that the evolution of Planet Earth continues to unfold.

Monday, November 1, 2010

The March of Autumn

November, like March, can be a fickle month in the American Heartland; though known for blustery weather and gray skies, both months offer a fair number of mild, sunny days. But an unsettled jet stream, tugged by summer and winter, produces intermittent showers and storms, some of which harbor snow.

Many prefer the stability of January or July but, for the naturalist, these transition months have much to offer. The weather patterns, themselves, can be fascinating, prompting adaptation by a wide variety of creatures, including humans. And, for birders, these months host the peak of the waterfowl migrations, offering some of the true spectacles in nature's year.

Following the splendid month of October, November has a rougher edge and generally brings the first significant round of winter weather; for those who dread the cold and snow, its value is redeemed only by the prospects of football and the beloved Thanksgiving holiday. But, for the rest of us, November offers crisp, invigorating weather, active and conspicuous wildlife, the inspiration of migrant geese and the reassurance that nature's cycle will stay the course.

Sunday, October 31, 2010

Day of Fear

Today, the rituals of Halloween will unfold, man's effort to express and illuminate the fears that pervade our lives. The greatest of these, of course, is the fear of death, unique to the human species; there are other fears that are also buried in our collective consciousness, such as fear of the dark, which stems from our limited capacity to function at night and the threat that nocturnal predators posed to early human tribes.

But most of our fears are learned, the products of terrifying childhood experiences or directly ingrained by our parents, teachers and religious leaders. Fear of wild creatures, such as spiders, snakes or mice, usually stems from the anxiety that they produced in our trusted guardians while fear of the unfamiliar, often manifest as racism and intolerance, arises from the influence of prejudiced and ignorant authority figures. Perhaps most pervasive are the fears ingrained by religion, causing us to loathe many of the traits that make us human; indeed, we come to fear the repercussions of our innate human behaviour, expecting eternal punishment at the hands of a vindictive God.

The fears that we expose this evening are almost all figments of the human mind, born of anxiety, ignorance and irrational thought. Unfortunately, they are reinforced by the mysticism of human culture and, in many cases, continue to threaten our peace and happiness. Fear is not the tool of the devil; rather, it is the tool of priests, politicians and all who strive to control our lives.

Saturday, October 30, 2010

The Ural Mountains

Extending north to south through western Russia, the Ural Mountains formed from the collision of two proto-continents, some 250-300 million years ago. Since eroded to a relatively low but rugged chain of peaks and ridges, the Urals stretch for more than 1500 miles, from the Kara Sea to the Ural River Valley; the latter flows through the semiarid steppes of northern Kazakhstan. While the highest peaks are only in the range of 6200 feet, the varied ecosystems of the Urals make them of special interest to naturalists; geographers are also enamored with this range, traditionally accepted to be the border between Europe and Asia.

The northernmost Urals, which extend into the Kara Sea as a chain of islands, are heavily glaciated; possessing a Polar climate, this region is sparsely vegetated and native wildlife, typical of the Arctic, include snowy owls, lemmings, arctic fox, reindeer and rock ptarmigan. In the middle Urals, where the highest summits are located, rich, coniferous forests cloak the mountains, home to elk, brown bear, wolves, wolverines, lynx and sable. Further south, deciduous forests predominate, giving way to semiarid grasslands of the Kazak steppes; among the unique wildlife in these drier areas are susliks, a species of ground squirrel, and jerboas, nocturnal jumping rodents that inhabit desert regions across the globe.

The mountains, themselves, are composed of metamorphosed sediments of the early to mid Paleozoic Era; volcanic basalts are also present, especially along the eastern slope of the range. The southern Urals drain to the Caspian Sea via the Ural River while the central and northern Urals drain to the Kara Sea of the Arctic Ocean; the Pechora River rises along the western slope, coursing through karst landscapes on its way to the Sea while the Ob River and its tributaries drain the eastern slope. Rich in minerals, precious metals and semi-precious stones, the Ural Mountains have long been exploited by human civilizations; fortunately, their harsh climate and rugged terrain have served to protect a wide diversity of plants and animals.

Friday, October 29, 2010

First Freeze

For the first time this season, winter has poked a finger into central Missouri; this morning, the temperature hovered just below 32 degrees F. While this first freeze is about two weeks late, it is a significant event nonetheless, ushering in the dark, quiet season. The winter solstice is still two months away and we'll surely have plenty of mild, sunny weather in the coming weeks but the first jab of winter lets us know that the tide of the seasons has turned.

This morning's freeze will permanently silence many of our insects and send others to the shelter of leaf mulch and basements; some will emerge in the mild days ahead but, slowed by the autumn chill, they will be easy targets for the birds, reptiles and small mammals that continue to prepare for the depths of winter. For humans, it is an opportunity to test the furnace, stoke the fireplace and, of course, complain about the weather.

Some dread the chilly days and frigid nights that lie ahead and, like certain mammalian neighbors, will hibernate until spring invades the Heartland. But many of us are invigorated by the cold weather and look forward to the snowy days and star-filled nights. We are inspired by the hooting of owls, we relish the scent of wood smoke and we long to tramp through the peaceful, bugless landscape of winter.

Wednesday, October 27, 2010

Control & Happiness

We humans, having the capacity to make plans and set goals, strive to be happy. While we are carefree as children, we come to realize that our happiness is dependent upon the degree of control that we have over the course of our lives. Conversely, unhappiness often results from the sense that we have lost control, whether in our relationships, our career, our health or in some other aspect of our life.

Some choose to live with unhappiness, convinced that their life is governed by a divine force and that suffering is the key to their eternal reward. At the other extreme are the hedonists, willing to forgo personal responsibilities in pursuit of their own gratification. Fortunately, the great majority of humans strive to balance their own happiness with the obligations that they feel toward their families, their friends and their fellow citizens. Indeed, unless based on this balanced approach to life, human society could not endure.

But, as individuals, we must learn to recognize when the loss of personal control is eroding our mental and physical health. Responsible choices can be made to restore that control, though a willingness to face some degree of risk is often essential. Martyrdom serves no one and, since we only have one life to live, an openness to change will help to ensure that it is a happy one.

Tuesday, October 26, 2010

Wind Storm

Produced by a ripple in the high energy jet stream, a potent storm has developed over the Northern Plains and, as of this morning, is centered over Minnesota. Its trailing cold front blasted through Columbia at 1:45 AM, bringing rain and gusty winds but no severe weather; those farther east, where the air has been primed by a swath of Gulf moisture, may not fair as well and severe thunderstorms are forecast for the Ohio Valley and Great Lakes region. Worse yet, blizzard conditions are expected northwest of the storm's center, where wrap-around moisture, cold air and strong winds will collide.

The primary damage from this storm will likely be from high wind gusts; its central low matches that of many hurricanes and its wind field extends from the Dakotas to the Ohio Valley. While we have dodged the severe weather, central Missouri remains within the storm's massive reach and strong westerly winds should persist for the next 24 hours.

Expected to drift to the northeast, the storm will likely produce most of its havoc in the Great Lakes region, shutting down airports and shipping lanes as its ferocious winds rake the area. After a beautiful, mild October, this storm reminds us that winter's fury will soon descend on the Heartland.

Sunday, October 24, 2010

Fox in the Mulch

Since we bought our Littleton, Colorado, farm in 1990, a large pile of mulch has been accumulating and compacting in a back corner of the property. This week, while adding limbs to an adjacent brush pile, I noticed an opening at the base of mulch and immediately suspected that another fox was living on our farm. In recent years, a pair of red fox had denned beneath our barn and, every spring, their toddlers would appear, chewing on the garden hose, wrestling on the jacuzzi deck or chasing each other through the pastures.

My suspicions regarding the new resident were confirmed later in the week when a fox suddenly scrambled over the back fence as I approached the area. He (or she) has certainly picked a convenient site, hidden within an overgrown and largely ignored parcel of land, where there are surely plenty of field mice to fuel his activity. We can now look forward to the remnants of his kills (goose feathers, fish heads, squirrel legs) appearing on our property throughout the coming winter.

As other regional farms have morphed into suburbs, wild residents have fewer sites on which to den, nest and hunt. The fox is certainly welcome on our farm and, if we are lucky, a new set of pups might emerge to entertain us next spring. Sharing the land with our wild neighbors is, after all, the most appealing aspect of owning a farm.

Saturday, October 23, 2010

Crossing the Storm

As I left Denver this morning, a large storm system was centered over northeastern Colorado. A cool north breeze was flowing southward along the Front Range and an occasional pocket of drizzle coated the windshield. Further east, an upslope flow had developed on the north side of the Palmer Divide, resulting in dense fog, with visibility reduced to ten yards or so.

Once I descended to Limon, the skies cleared and remained so through western Kansas. Strong southerly winds developed east of Russell, spinning the turbines of the Smoky Hills Wind Farm and signaling that I was now east of the cold front. Since the air contained little moisture, only scattered, high clouds marred the deep blue sky; approaching Topeka, however, a band of billowing cumulus clouds appeared on the horizon, indicating that Gulf moisture was now clearly in play. Showers swept across the highway in eastern Kansas and thunderstorms, with possible tornadoes, are forecast for central Missouri this evening; so far, just light rain and gusty south winds.

As is characteristic throughout the Northern Hemisphere, winds flow counterclockwise around the center of low pressure, producing the sequence of events that accompanied my drive. A chilly north wind and wrap-around moisture produced the showers and upslope fog west of the storm while strong southerly winds, sweeping Gulf moisture into the Heartland, has set the stage for severe weather ahead of the front. In the course of an 11 hour drive, I had crossed the storm and experienced both its cold and warm sectors.

Friday, October 22, 2010

Flowing Back in Time

West of Glenwood Springs, Colorado, the Colorado River passes through the Grand Hogback and enters the Colorado Plateau, a vast geophysical province that covers western Colorado, eastern Utah, northern Arizona and northwest New Mexico. Characterized by horizontal layers of bedrock, increasing in age from top to bottom, the Plateau is a scenic landscape of mesas, buttes and canyons, all sculpted by the Colorado River and its numerous tributaries; from its entry point in western Colorado to its exit west of the Grand Canyon, the River has cut through 550 million years of geologic history (early Tertiary, Mesozoic and Paleozoic), not to mention part of the ancient Precambrian basement that underlies these sediments.

Just west of the Grand Hogback, which marks the western edge of the Rocky Mountain Province, the Colorado flows across Tertiary terrain; to its north is the Roan Plateau, capped by Eocene sediments (50 million years old) and, to its south, is the massive bulk of Battlement Mesa, protected from erosion by a layer of Tertiary basalt. Further along, the River enters the Mesozoic, cutting through the Cretaceous sandstone of Debeque Canyon and then running atop the Cretaceous shale of the Grand Valley; the Book Cliffs, also Cretaceous in age and exposed below the younger Roan Plateau, run along the north edge of the Valley, extending into Utah. The River curves around the northern flank of the Uncompaghre Plateau and angles southwestward, carving through the scenic Jurassic and Triassic redrocks of Utah's Canyon Country.

Reinforced by flow from the Green River, the Colorado begins to dig into Paleozoic sediments at the entrance to Glen Canyon, now flooded by a massive reservoir; this Permian sandstone is only visible along the eastern backwaters of the lake, which is bordered by high walls of Jurassic Navajo sandstone further downstream. Beyond Glen Canyon, in northern Arizona, the Jurassic sediments disappear and the landscape is composed primarily of Triassic and late Paleozoic (Pennsylvanian and Permian) rocks; these layers, 200-300 million years old, are well exposed in Marble Canyon. Having received additional flow from the San Juan and Little Colorado Rivers, the Colorado enters the Grand Canyon, which it carved from a stack of Paleozoic sediments, one mile thick; Permian Kaibab limestone caps the Canyon walls while, at their base, the River is cutting through Precambrian Vishnu Schist, more than 1.7 billion years old.

Thursday, October 21, 2010

Into the Wilderness

Needing a break from the farm work and granted another sunny, mild day, I opted for a hike in the mountains and headed for the Deer Creek Trailhead, which provides access to the southeast edge of the Mt. Evans Wilderness. Picking up the Tanglewood Trail, I snaked upward through the rich, subalpine forest, serenaded by mountain chickadees and scolded by red squirrels. Not having the time (or energy) to reach timberline, I settled for distant and transient views of Bandit Peak and Mt. Rosalie but was rewarded with fresh mountain air, the fragrance of a coniferous forest and the beauty of clear, turbulent streams.

Wilderness hikes offer solitude and tranquility but do not always provide the wildlife diversity that some might expect. Though interesting encounters can and do occur, the native creatures have miles of open space to explore and are not in the business of entertaining human visitors. Of course, there are exceptions, especially if a picnic lunch unfolds or a campsite is established; then, the sounds and aromas attract some of our more curious neighbors, including Steller's jays, gray jays, Clark's nutcrackers and those supreme opportunists, black bears.

In the end, wilderness exploration is all about the landscape, a chance to understand the topography and immerse yourself in the ecosystem. Additional benefits, no less important, are the opportunities to test your body, relax your mind and recharge your soul. For these reasons alone, all wilderness must be protected.

Wednesday, October 20, 2010

Colorado Junipers

Favoring sunshine and semi-arid soil, junipers are found throughout Colorado, from High Plains escarpments to the canyon walls of the Colorado Plateau; they generally occupy elevations between 5000 and 8000 feet but may grow as high as 9000 feet on south-facing slopes west of the Divide. Rocky Mountain junipers (western red cedars) are found throughout this range while Utah junipers are limited to the Western Slope; one seed junipers, oval-shaped and shrub-sized, are closely associated with pinon pine woodlands and are thus common across southern and western Colorado. Finally, eastern junipers (known as eastern red cedars) are widely planted along the Front Range urban corridor.

While adding diversity to any landscape, junipers are especially appealing since they attract a wide variety of wildlife. Elk, deer and pronghorn browse on their foliage and their fruit (small, berry-like cones) is consumed by a large number of birds and small mammals. In addition, the dense foliage of these trees offers shelter from the cold wind and heavy snows of winter, another trait that appeals to our native wildlife.

Fortunately, we have a large number and variety of junipers on our Littleton farm, attracting a diverse group of visitors, especially during the colder months of the year. Townsend's solitaires, bohemian waxwings, cedar waxwings and the more common fruit-eating birds (robins, house finches, jays, magpies, doves) regularly grace the scene; western tanagers also brighten the junipers during their spring migration.

Tuesday, October 19, 2010

The Nature of Homophobia

As the political season heats up, gay rights have once again become fodder for conservative talk show hosts, politicians and religious leaders, all of whom use disinformation to back their arguments. As in all forms of discrimination, ignorance sets the stage for blind acceptance and large segments of our society harbor the view that homosexuality is a behavioral choice (or, at best, an illness) that may be taught or transmitted to innocent children. They either reject or are oblivious to the fact that homosexuality is an inherited trait, no less innate than blond hair or dark skin; indeed, there is substantial scientific evidence that up to 10% of humans are homosexual or bisexual.

Of course, early religious indoctrination and parental attitudes also influence our views about homosexuality. Like other beliefs that are ingrained during childhood, negative feelings about homosexuality are difficult to restrain, especially amidst the emotional turmoil of the teenage years. The hatred and self-doubt that is generated during this period account for the bullying and suicides that have recently dominated the news; in fact, gay teens are four times more likely to commit suicide than their heterosexual counterparts.

Ironically, the most vocal opponents of gay rights are often attempting to disguise their own homosexual or bisexual feelings. They rail against the secretive and promiscuous behavior of many gays while denying them open acceptance, military or teaching opportunities and marriage rights. Once again, hypocrisy raises its ugly head in American society and many of her most productive and creative citizens must either suffer in silence or be branded as social outcasts.

Monday, October 18, 2010

Pheasant of the Plains

This was a beautiful day for traveling across the Great Plains of North America. Under partly cloudy skies and a mild air mass, the grasslands had taken on the golden hues of autumn and splotches of yellow and rust dappled the streamside woodlands. While migrant waterfowl were noticeably sparse, birding along the Interstate was fairly productive, dominated by crows, starlings, red-tailed hawks, meadowlarks and northern harriers. A large flock of longspurs crossed the highway in eastern Colorado and a few ring-necked pheasants foraged along a cropfield in western Kansas.

Ring-necked pheasants, native to Asia, were first introduced in North America during the mid 19th Century and have since been released in many parts of the U.S.; indeed, more than 30 subspecies can be found in our country, attesting to their popularity as a game bird. Favoring open country, these birds are common on the grasslands of the Upper Midwest and Great Plains, where they feed on waste grain and a wide variety of natural foods (seeds, nuts, berries and insects). Since they rely on tall grasses and thickets for cover, regional populations are often threatened by extensive tilling and crop production.

The large, brightly colored males gather harems in early spring and the females dig a shallow nest on the ground; an average of ten chicks are hatched by late spring and remain with their mother for three months. Those that survive predation by hawks, fox and coyotes are fully grown and independent by late summer; it is then that they must also avoid the watchful eyes of human hunters. While pheasants prefer to escape into dense cover when threatened, they flush vertically if startled and are capable of swift flight over short distances; it is this trait and their tasty flesh that have sealed their fate as popular hunting targets.

Sunday, October 17, 2010

A Motley Crowd

Those of us who regularly observe birds at the backyard feeder come to appreciate the varied personalities of our avian visitors. House sparrows and house finches, while skittish, mob the feeder, gorging themselves and defending their positions; they are focused on survival and have no interest in rules of etiquette. Chickadees and titmice, agile and opportunistic, dart in to grab one seed at a time, taking it away to devour in peace; optimistic and carefree, they are highly adaptable and are less concerned that the stash may disappear in their absence.

More fiscally conservative, white-breasted nuthatches also grab one morsel at a time but take it away for storage in the crevices of tree bark; they are preparing for leaner times, when winter sets in and the feeder runs dry. Less concerned are the unflappable mourning doves, observing the chaos from nearby branches or drifting in to search for seed that has fallen to the ground; they and the dark-eyed juncos are content to receive what others have discarded.

Woodpeckers and jays, possessing a distinct size advantage, drop by anytime, knowing that the minions will scatter as they approach; wary only of the occasional sharp-shinned hawk, they partake of the bounty at their leisure, paying little attention to their smaller, hapless cousins. Finally, the cardinals, too mature and regal to abide with the rowdiness, visit the feeder in the early morning and late daylight hours, when their antic-prone neighbors are back at the roost.

Saturday, October 16, 2010

Sphinx Moths

Returning home yesterday afternoon, I found a large, attractive moth on the wall of our front porch. It was a white-lined sphinx moth, a member of the sphinx moth family, which includes hawk moths and hummingbird moths; the latter name derives from their large size, rapid flight and feeding behavior, which involves hovering over tubular flowers to extract nectar. Indeed, sphinx moths, like hummingbirds and certain bats, are important pollinators in most desert regions.

Their large, colorful caterpillars may be encountered in roaming armies, traversing roads or trails; each species has its favored plant food which, unfortunately, includes tomatoes and apple trees. Before pupating, the caterpillar usually enters an underground chamber or settles within the crevices of rock walls or wood piles; most species overwinter in the pupal form.

The attractive adults generally feed at dawn or dusk though some species are active during the day and others are strictly nocturnal. Often mistaken for hummingbirds, as mentioned above, they live for three to four weeks, feasting on nectar, entertaining humans and producing their next generation.

Friday, October 15, 2010

Man & Mountains

Having evolved in the shadow of Kilimanjaro, man has long been enchanted with mountains. We, and perhaps our immediate hominid predecessors, were the first species to appreciate the significance of these highlands, understanding both the travel difficulties that they impose and the multiple benefits that they offer; for early man, the latter included food sources, water, shelter and defense from hostile tribes and predators. Of course, the peaks themselves, reaching toward the stars and into the clouds, were often infused with mystical significance, the home of the gods, both good and evil.

Today, we have a better understanding of these landforms but are no less inspired by their presence. Offering both an escape from summer heat and a playground for winter sports, they are also a destination for hikers, climbers, hunters and naturalists. Indeed, for the naturalist, they offer a variety of life zones within a short distance, yielding a spectacular diversity of fauna and flora.

Essential elements of any scenic landscape, mountains are appreciated for their beauty and their grandeur, the ultimate symbols of permanence and stability. But, as students of natural history know, they are just as vulnerable to the forces of nature as any other landform. They, too, are transient features of the landscape, destined to be flattened by the erosive power of wind, water and ice; their summits will yield beach sand and their slopes will enrich the plains. Fortunately, for the descendants of humans, other mountains will rise as tectonic plates collide and subduct; these, too, will catch the first light of dawn and inspire those beings to climb toward the sky.

Thursday, October 14, 2010

The Miners & Humanity

Scenes of joy were beamed across the globe over the past two days as 33 Chilean miners were rescued from their ten week ordeal, entombed within the Earth. All humans, Americans and Russians, Palestinians and Israelis, Indians and Pakistanis, could relate to the emotions on display as the miners were reunited with their families and friends.

Some, of course, saw God's hand in these events and will use the images to further their message of divine intervention. Most of us, however, focused on the humanity of this spectacle, admiring the courage of the miners, the skills of the rescuers and the devotion of their loved ones. For a brief moment in time, we reunited as a human community, oblivious to the national, ethnic and religious barriers that divide us.

It is this common human spirit, after all, that allowed our species to populate the globe, to endure the natural elements that confronted us and to achieve the level of knowledge and technology that permitted this rescue to unfold. Hopefully, these scenes of cooperation and joy will have lasting effects, reigniting a commitment to the welfare of fellow humans across our magnificent planet.

Wednesday, October 13, 2010

Jack-o-Lantern Mushrooms

Mushrooms, the spore-producing fruit of fungi, generally prefer cool, moist conditions and are thus rarely encountered during the heat of summer. Indeed, spring and fall are the seasons to observe or collect mushrooms and autumn often offers the greatest variety.

This week, Jack-o-Lantern mushrooms have appeared in our yard, clustering near old stumps, atop the wood mulch or above decaying tree roots. Named for their orange coloration and the fact that their gills, under the right conditions, produce a faint, greenish glow, these mushrooms initially have a convex cap which flattens to a disk and then takes on a larger,cupped shape as they grow; within a few more days, the cluster begins to dry out and crumbles into a darkened mass. Though fragrant (for fungi) and attractive during their growth phase, Jack-o-Lantern mushrooms are toxic to humans, producing a gastroenteritis if consumed.

Like all fungi, this species feeds on organic debris and most of the organism consists of mycelia, thread-like tendrils that course along and through decaying wood. Jack-o-lantern mushrooms are closely associated with oak woodlands and are common in forests and suburbs east of the Rocky Mountains; a related species is found in California. Once mature, the mushrooms produce millions of spores which are spread about by rain, wind, insects and small mammals, destined to become the next generation of saprophytic recyclers.

Tuesday, October 12, 2010

Isolated Peaks & Monoliths

There are few natural landscapes more inspiring than a lone peak or isolated cluster of mountains that tower above the surrounding terrain. In some cases, this topography results from an especially hardened rock formation that has resisted the erosive forces of water, wind and ice. Mt. Monadnock, in southwest New Hampshire, provides an excellent example; composed of metamorphosed sediments from the Silurian and Devonian Periods, this mountain has withstood the advance and retreat of the Pleistocene Glaciers.

Many of our isolated peaks are volcanic in origin, rising above expanding chambers of magma and coated by recurrent lava flows or explosive eruptions. The massive volcanic domes of the Cascades are best known but volcanic peaks are also widespread in the Southwest; Sierra Grande, a dormant stratovolcano in northeast New Mexico, Mt. Taylor, west of Albuquerque, and the San Francisco Mountains, north of Flagstaff, are a few examples.

Finally, many of our natural monoliths developed beneath the surface, extruded as magma within layers of sedimentary rock. Later, as the terrain was lifted and the encasing sediments eroded away, these plutons or laccoliths were uncovered and now tower above their surroundings; Stone Mountain, near Atlanta, and Devil's Tower, in eastern Wyoming, are famous examples. Laccolithic mountains are especially common across the Colorado Plateau; these include Sleeping Ute Mountain in southwest Colorado and the La Sals, Abajo Mountains and Henry Mountains of southeast Utah. Shiprock, in northwest New Mexico, also developed from a column of underground magma before it rose with the Plateau and was unveiled by erosion.

Sunday, October 10, 2010

Birding without Binos

Binoculars are an essential tool for beginning birdwatchers, who learn to distinguish the individual species by close attention to their plumage and other physical characteristics. So too do avid birders rely on binoculars, ever vigilant for rare and accidental visitors to add to their life list.

For many of us, though, birding is simply part of our fascination with natural ecosystems. Once familiar with the birds that reside within or visit our region, we are more interested in how they fit into the ecology, anticipating their presence in the varied habitats. Since we usually bird while we hike and since we recognize birds by their shape, color and behavior, we are less concerned with close inspection, content to simply enjoy their company amidst the sights, sounds and smells of nature.

Of course, I often have my binos in the backpack, just in case I see something that is unusual or not readily identified. And, whenever I visit ecosystems or landscapes that are new to me, I am inclined to study the wildlife with more scrutiny. But, for my wanderings in familiar territory, birding is just a natural element of the overall experience and, for the most part, the binoculars stay in the backpack.

Saturday, October 9, 2010

The Chuska Mountains

Forming a topographic wall across northeastern Arizona and northwestern New Mexico, the Chuska Mountains are the remnants of an elongated, sandstone plateau. Almost sixty miles long, the range angles from the NNW to the SSE and sits atop a broader warp of the underlying Jurassic strata, known as the Defiance Plateau, which extends southeastward from the canyon country of Utah.

The sandstone of the Chuska mountains was deposited as windblown dunes but its age remains controversial; initially thought to have accumulated during the Oligocene, some 30-40 million years ago, most geologists now believe that the Chuska Sandstone is late Cretaceous in age (about 65-70 million years old). Heavily dissected by streams, the Chuska plateau ranges in elevation from 8000-9000 feet, with higher pediments, protected by a cap of basalt, rising to 9800 feet or more; these pediments are most numerous in the northern (Arizona) portion of the range and the volcanism that produced their caps occurred during the Pliocene (2-10 million years ago).

Today, the Chuska Mountains and associated ranges provide a high, forested corridor between the San Juans of southwest Colorado and the ranges of the Mogollon Rim, to the southwest; as a result, their varied fauna include elk, mule deer, black bear and mountain lions. To either side of the Chuskas, the terrain falls away to semiarid shrublands of the San Juan watershed; precipitation is greatest on the west side of the range and the deep, scenic canyons of this region include Canyon de Chelly National Monument, the site of artifacts from early American cultures. Now lying within the Navajo Nation, the high spine of the Chuskas provides almost 70% of the Nation's water supply.

Friday, October 8, 2010

Summer Billows Back

After getting shoved to the Gulf Coast by a series of cold fronts, summer has returned in the form of a broad atmospheric ridge that covers the eastern half of the U.S. Beneath this dome of high pressure, winds are light, air is sinking, cloud formation is suppressed and the early autumn sun bakes the landscape. Since the ridge also cuts off flow from the Gulf and the Atlantic, humidity within the dome is low, the warm days are comfortable and radiation cooling develops at night, allowing temperatures to fall into the forties and fifties (F).

Here in Missouri, we will top out in the low to mid eighties over the next few days and, though the foliage hints of autumn, it will feel more like summer. While we humans may be temporarily fooled by the atmospheric conditions, wildlife, responding to the waning daylight, will carry on with their preparations for winter, storing food or winging off to southern lands.

Summer has won this battle in its perpetual war with winter but the victory will be short lived. A trough in the West is bringing cool rains and mountains snows to the Four Corners region and, as the ridge of summer shifts to the east, conditions across the Heartland will become more seasonable. Time is on winter's side; the nights will continue to lengthen, the temperatures will fall and summer will be banished to the Southern Hemisphere.

Thursday, October 7, 2010

Back in the Dark

Two weeks after the autumn equinox, I am shrouded in darkness on my walks to work. From now until early March, there will be no sunlight to brighten my path and the surrounding landscape will be a mosaic of shadows.

Of course, there will be a much better chance to see the creatures of the night. Opossums may waddle across the road, raccoons may inspect the garbage cans and the faint silhouette of an owl may appear in a roadside shade tree or drift silently toward the nearby woods. And then there's the sky, with its moonlit clouds and brilliant stars, reminding me that our darkened planet is but a speck in this vast universe.

This morning's walk was highlighted by a flock of nighthawks, careening about the floodlights of a campus sports field. Feasting on moths to fuel their migration, they are heading south toward balmy weather and longer days and will not return until May flowers adorn our suburbs. By then, I will have walked many miles through the darkness of central Missouri, through cold rain and slushy snow, beneath thick clouds and star-filled skies. The edge of the dark season has indeed arrived.

Wednesday, October 6, 2010

Chickadee Gifts

Hang a new feeder in the backyard or fill an old one for the first time in the fall and, in almost every case, chickadees will be the first birds to accept your gift. Inquisitive, cheerful and trusting, these small birds seem to drift through life with a carefree attitude, oblivious to the many threats that nature may impose. Unlike their fair-weather cousins, chickadees do not depart for southern climes as winter sets in; rather, they roam about in small flocks, often in the company of titmice and downy woodpeckers, feasting on seeds, pupae and insect eggs.

Well equipped to endure the harsh winter weather, chickadees are a source of inspiration throughout the year, exuding optimism as they move through the woodlands or stop to partake of our backyard handouts. Though diminutive, they are undaunted by conditions that cause many animals (including humans) to retreat to sheltered dens. Once again, it is their positive attitude that seems to fuel their energy; they don't just cope with life...they seem to relish every minute.

When chickadees visit the feeder on those bleak winter days, they offer more than they receive. In return for our charity, they bestow faith and hope, a fair trade indeed.