Wednesday, December 31, 2008

Celebrity Worship

Throughout human history, our species has been enamored with celebrities. Initially, these individuals were shamans and tribal chiefs, replaced by kings, queens, princes, warriors and priests as time moved on. Though titles and identities have changed, man confers celebrity for a few primary traits: power, physical prowess, wealth and beauty.

Today, in modern Western society, our celebrities are primarily athletes and entertainers and our image of them is somewhat schizophrenic. On the one hand, we expect them to be more than they are; interested in every aspect of their lives, we support the industries that fawn over them, wear jerseys emblazoned with their names and pay ridiculous fees just to be in their presence. Convinced of their importance, we readily overlook their foibles (multiple divorces, drug use, criminal behavior), which often only enhance their celebrity. On the other hand, our sadistic side feeds the gossip mills and the cable shows that focus on their dysfunctional lives; as individuals, they are afforded little privacy.

Man's tendency to worship celebrity is a reflection of the human condition. Well aware of our own flaws and limitations, we are reassured that others have conquered them. And while admiring the talent and achievements of these celebrities, we are also comforted by their failures. In the end, they boost our own self esteem.

Tuesday, December 30, 2008

Winter Marsh

Our Midwest wetlands are surely not as fascinating during the winter as they are during the warmer months. The colorful songbirds have departed for southern climes and wetland wildflowers have long gone to seed. No frogs croak from the shallows and no turtles lounge in the mid day sun. Rails have left their backwater haunts and most waders have moved on to milder wintering grounds. Perhaps most striking is the silence, broken only by the distant call of geese or the friction of dried cattails in the cold winter wind.

But there is still much to see in the winter marsh. A variety of sparrows gather in the dense, dead vegetation, escaping the wind and searching for seeds; song and white-throated sparrows are most common but American tree, fox, Harris' and swamp sparrows may also be found. Northern harriers and sharp-shinned hawks swoop across the marsh, red-tailed hawks circle overhead and barred owls survey the scene from nearby woodlands. If open water persists, wintering ducks (mallards, gadwall, green-winged teal) may be seen and great blue herons, seemingly out of place in the cold, snowy weather, often stalk the shallows.

Those who visit early or late in the day have the chance to observe marshland mammals, most of which remain active through the year. Mink hunt along the banks or man-made dikes, searching for mice, muskrats and unwary ducks. Raccoons and opossums, opportunistic as they are, scour the marsh for anything edible while beaver and muskrat ply the open waters. The colors and noise may have faded but there's still plenty of activity in these crucibles of life.

Monday, December 29, 2008

The Rise of Endotherms

Life evolved in the ocean, some 3.6 billion years ago, and, for most of its history on Earth, has been confined to the sea. Shelled marine life had evolved by 600 million years ago (MYA) and both sharks and bony fish appeared during the Devonian Period, some 375 MYA. The first land animals, millipede-like organisms, crawled ashore during the Silurian (420 MYA), giving rise to terrestrial insects and spiders over the next 100 million years. Amphibians diversified and reptiles evolved during the Carboniferous Period (350-270 MYA) and, by the Permian (270-225 MYA), mammal-like reptiles appeared.

All of the above animals are/were ectotherms: they have an internal body temperature that matches their surroundings (some sharks, fish and insects, able to generate heat in certain muscle groups, are better classified as heterotherms). Early in the Mesozoic (200 MYA), endotherms, initially represented by small dinosaurs and the earliest mammals, evolved; these Triassic creatures (joined by the first birds during the Jurassic) were able to regulate their internal temperature by controlling regional blood flow (to conserve or dissipate heat), by shivering, sweating (or panting) and by maintaining a high metabolic rate. The evolution of fur, feathers and subdermal fat provided additional insulation and improved heat conservation.

Endotherms, most of which are homeotherms (maintaining a stable core temperature), are less restricted by their environment, have colonized all regions of the globe and can remain active during all seasons. Man, of course, has little external insulation but had the intelligence to develop clothing, control fire and build shelters. Mammal hibernation adds a final twist to the story; more than a behavior to escape the cold, torpor is an active process, lowering the metabolic rate, producing hypothermia and conserving energy during periods of reduced food supply.

Sunday, December 28, 2008

Palo Dura Canyon

The High Plains of North America are coated primarily by erosional debris from the Rocky Mountains and by windblown deposits from western volcanoes. The entire province was tilted upward during the late Tertiary Period (the Miocene-Pliocene uplift) and mountain erosion increased during the Pleistocene, when glaciers and meltwater streams enhanced the process.

The eastern edge of the High Plains blends with the lower, Central Plains across much of the Continent but, in northwest Texas, the edge stands out as a prominent escarpment, incised by a series of canyons. The largest of these is Palo Dura Canyon, southeast of Amarillo. Averaging six miles in width and 800 feet in depth, it has been called the Grand Canyon of Texas and is surely one of the more scenic locations in the State. The Ogallala Formation (late Tertiary sandstone and conglomerate) forms the Caprock of the Canyon, which has a surface elevation near 3600 feet; Triassic rocks comprise upper layers of the Canyon, overlying Permian strata, which harbor seams of white gypsum. These Permian rocks represent the upper layer of the Permian Basin, which extends southwestward, where it is covered by younger Mesozoic and Tertiary sediments.

Protected as a Texas State Park since 1934, Palo Dura Canyon was eroded over the last million years by the Prairie Dog Fork of the Red River. It's name, which means "hardwood" in Spanish, refers to the plentiful mesquite and juniper trees that cover the canyon slopes; cottonwoods and willows, less drought tolerant, cluster along the River on the canyon floor. A variety of shortgrass species, yucca, prickly pear cactus and western wildflowers also adorn the Park. Resident wildlife include deer, coyotes, wild turkey, scaled quail, roadrunners and western diamondback rattlesnakes; among the many raptors are golden eagles, prairie falcons and ferruginous hawks. The Park, 12 miles east of Canyon, Texas, is reached via State Route 217; an 8 mile road and numerous trails provide access to this scenic refuge.

Saturday, December 27, 2008

Weather and Wildlife

Today provided inspiration for indoor activities. Heavy rain, falling temperatures and the promise of ice have kept most of us out of the elements. And, equipped with heated homes, cars, malls, theaters and supermarkets, there was little need to venture into the great outdoors. But our wild neighbors, who fend for themselves, have little choice; they must endure the cold rain or skip dinner!

Of course, their fur and feathers provide ample protection as they hunt for prey or scour the landscape for nuts, berries and hibernating insects. In the midst of this morning's downpour, a pair of titmice moved between the feeder and suet block, their distinctive crests plastered to their skulls. At the same time, a fox squirrel, using his tail as an umbrella, managed to dislodge a pine cone feeder before carting it off to his den. And throughout the day, despite the weather, the usual mix of residential birds paid their respects.

Beyond their natural protection and survival skills, wild creatures are not burdened by man's preoccupation with the past and the future. They do not dwell on the glorious days of autumn or anticipate the coming spring. They have no thermometers or calendars to check and are not inclined toward procrastination. Rather, they are focused on the present and must take what comes; their survival depends on a day to day approach to life. If only we could adopt that attitude!

December Deluge

In advance of the latest cold front, strong southerly winds brought warm, humid air into the Heartland over the past 24 hours; at dawn, it was 68 degrees F in central Missouri (five degrees warmer than it was in Tampa, Florida). But, by mid morning, distant thunder warned of a coming change.

The line of thunderstorms arrived at 9:30 AM, accompanied by torrential rain and gusty winds; a doppler-indicated tornado, northeast of Columbia, triggered the warning sirens, which blared across the city for ten minutes or so. The downpour has diminished over the past hour but a second round of storms, attached to the cold front, is now approaching from the northwest and more heavy rain is expected. Since the ground remains frozen from our recent Arctic weather, runoff will be significant and a flash flood watch has been issued for most of the region.

Behind the front, temperatures will fall through the day, bringing a mix of sleet and snow by this evening; the overnight low is forecast to be in the mid 20s. After a brief taste of spring, more seasonable conditions should prevail throughout the coming week.

Friday, December 26, 2008

Barrier Islands

Barrier islands, among the most transient landforms on the planet, are common along the Atlantic and Gulf Coasts of North America, from Cape Cod southward. Formed by the action of waves and currents, these narrow islands are essentially offshore dunes, stabilized by a variety of grasses, shrubs and trees; this natural vegetation, tolerant of the salty and sandy conditions, is derived from seeds that blow out from the mainland (man has since added his own assortment of ornamental species).

Initially inhabited only by sea birds, marine mollusks and temporary visitors (such as sea turtles), most of the islands now harbor beach resorts, perched precariously on these shifting mounds of sand. While modern structures are anchored into the deep bedrock, all development on the offshore islands is prone to damage or destruction from the tropical storms and hurricanes that sweep across the region. In addition, island wildlife is threatened by mainland species (such as raccoons) that now reach these sandy refuges via man-made bridges.

Barrier islands form along coasts were the Continental Shelf is broad and shallow, making them especially susceptible to storm surge and wave erosion. Islands not destroyed or cut apart by storms will eventually merge with the mainland as the intervening bay is filled in by river sediment and by sand pushed through the inlets. Of course, humans keep their boat channels open by dredging, but, in time, nature will have her way!

Wednesday, December 24, 2008

Man and his Gods

Throughout human history, which spans 125,000 years, man has imagined gods and mystical beings that would supply his needs (rain, a good harvest, wealth) and protect him from danger (storms, warfare, illness, death). Over time, the identity of these deities has evolved but their purpose remains the same. Today, our preferred image is determined by our culture and, as in the past, is ingrained in our psyche during childhood.

One would like to think that such beliefs are harmless social customs that promote the common good. But anyone with a knowledge of history understands the dark side of religious fervor; too often, it is a source of hate, discrimination, intolerance and persecution.

Tomorrow, Christians celebrate the birth of Jesus, who, they believe, was the Son of God. By all accounts, he led a simple life, preached tolerance and encouraged his followers to share their talents and wealth. Two thousand years later, the Christian Church has become a political and financial power broker, run by entrenched hierarchies and media entrepreneurs. Conservative Christian zealots, self-righteous and narrow-minded, foster intolerance and work to impose their social agenda. Unfortunately, there are plenty of fearful, uneducated, guilt-ridden followers to heed their call, marking the latest chapter in man's quest for immortality.

Merry Christmas to all!

Tuesday, December 23, 2008

The Misnamed Woodpecker

Most abundant in pine lands and bottom woods of the Southeast, the red-bellied woodpecker is common in open woodlands and residential areas of eastern North America, from southernmost Canada to Florida; those that breed across northern limits of this range move southward in the winter. Feeding on a wide variety of insects, nuts and berries, the red-belly often visits backyard feeders, especially during the colder months, and it is then that novice or casual birders first notice it.

A bit smaller than the similarly shaped flicker, this woodpecker is identified by his black and white "ladder back", beige underparts and bright red crown (limited to the nape in females); ironically, it is named for a pale red blush on its abdomen which is often invisible in the field. A distinctive, rolling "churrr" usually announces its presence; unlike flickers, the red-bellied woodpecker is seldom found in flocks.

Perhaps this species should have been called the zebraback or red-crowned woodpecker but the power brokers of the bird world make these decisions. Regardless of its name, the red-belly, attractive and beneficial, is always a welcome visitor in our yard!

Monday, December 22, 2008

Out of the Dark

Having just endured the longest night of the year, our daylight will gradually lengthen until the summer solstice, on or about June 21; this reflects the tilt of the Earth's axis, causing the Northern Hemisphere to receive increasingly direct solar radiation through the period. Of course, the sun angle will remain too low to provide significant warmth at our latitude for another two months and there will be plenty more winter weather before spring takes hold.

Even so, it is reassuring to know that the days will be lengthening. Humans are not naturally equipped for the cold and the dark. We evolved in the Tropics and, regardless of our personal preferences, we have a deep-seated connection to warm, sunny weather. Besides, with the exception of deep ocean ecosystems, all life on Earth is dependent on the sun. Primitive man, though devoid of scientific tools, knew this instinctively and marked the solstice with various rituals. Today, we understand the astronomical cause for the event but it is no less comforting.

Sunday, December 21, 2008

The Gangplank

As the Mesozoic Era ended, 65 million years ago, the dinosaurs were dying out and the Rocky Mountains were crumpling skyward. In concert with their rise, the forces of erosion began to work on these highlands and aprons of debris, carried by wind and water, spread out from their flanks. Throughout much of the Tertiary Period, the mountain summits barely poked above these vast plains of debris.

Then, in the Miocene Epoch (some 20 million years ago) a second, more general uplift of the Mountain West began, adding 5000 feet to elevations across the Colorado Plateau and Rocky Mountain Province. This uplift, which continued into the Pliocene, accelerated stream erosion throughout the region; the process was further enhanced by the cold, wet climate of the Pleistocene, as mountain glaciers carved deep canyons and massive amounts of meltwater carried away much of the erosional debris that had enveloped the mountains.

When early explorers and settlers reached western North America, the Front Range of the Rockies imposed a formidable barrier from Canada to New Mexico. Though steep, narrow passes were adequate for travel by foot or horseback, the search for a train route uncovered an area in southern Wyoming where Tertiary sediments had survived the elements of erosion. Known to geologists as The Gangplank, this wide, natural pass west of Cheyenne offers a gradual climb between the watersheds of the North and South Platte Rivers; the Union Pacific line and Interstate 80 use this route today, crossing the Laramie Range between the High Plains and the Laramie Basin.

Saturday, December 20, 2008

Bird Count

More than most people, I enjoy solitude, especially when visiting wild areas. The sights, sounds and smells of nature are, in my opinion, best appreciated in the absence of human conversation. But twice each year, near Christmas and in the spring, I take part in the annual Audubon birding counts, established to monitor the status of regional bird populations.

Our group is assigned to rolling farmlands south of Columbia, between the Missouri River, on the west, and U.S. 63. We gathered just before dawn and set out to survey are region, winding along country roads and stopping at selected sites to look for birds. It was a cold, gray day but the birding was decent and most expected species were found; as usual, juncos, crows, robins, blue jays, cardinals, flickers and starlings were among the more common. We also saw red-tailed and red-shouldered hawks, a lone bald eagle, a variety of woodpeckers, yellow-rumped warblers, purple finches, swamp sparrows and northern mockingbirds; during our six hour excursion, forty species were tallied.

The highlight of today's count was the large number of cedar waxings. In most years, we see several flocks of these attractive birds, generally yielding a total of fifty or so. Today, we saw hundreds of waxwings; in fact, it was the most numerous bird on the list, even surpassing our tallies for juncos and starlings. Though the reason is uncertain, it is likely that these nomadic birds abandoned more northern parts of their range after recent heavy snows across that region.

Friday, December 19, 2008

The Tahoe Basin

Though the Sierra Batholith formed back in the Mesozoic Era, this massive pluton of rock did not rise to create the Sierra-Nevada Range until the late Tertiary Period, about 3-4 million years ago. As it rose, the forces of erosion began to sculpt its summits and fault lines developed along its margins. Along the northeast edge of the batholith, a block of crust (known as a graben) dropped between parallel faults, with the Sierra rising to its west and the Carson Range uplifted to its east; the resulting basin is now known as Tahoe.

Streams from the surrounding highlands gradually filled the basin, the margin of which was continually molded by uplift, faulting, landslides, volcanic debris and glacial erosion; the latter was especially significant during the Pleistocene Epoch as glacial valleys formed along the west edge of the basin, glacial moraines altered drainage patterns and glacial meltwater added significant depth to the basin's lake. As one might expect, the surface level of Lake Tahoe, which now sits at 6225 feet, rose and fell significantly over the past 2 million years.

Today, the Truckee River is the only outlet from Lake Tahoe, flowing northeastward into the Great Basin, where it feeds Pyramid Lake. Lake Tahoe itself, with a maximum depth of 1645 feet and a surface area of 191 square miles, is the largest alpine lake in North America and the third deepest lake on the Continent (behind Great Slave Lake and Crater Lake). Known for its scenic setting and for the clarity of its water, Lake Tahoe sits above two fault lines, making the area prone to earthquakes and a potential tsunami; like all lakes, mountains, plains and canyons, it is a beautiful but temporary feature of our planet's landscape!

Center of the Storm

This week's powerful winter storm, on its way from Southern California to New England, passed just north of Columbia through the night. As it approached, energized by the jet stream, a thunderstorm erupted above the city, a startling event after days of frigid weather. Strong, counterclockwise winds, surrounding the central low pressure, brought in warm air from the south and, at dawn, it is 42 degrees F; winds are from the southwest, gusting to 40 mph.

As the storm continues its journey to the northeast, its trailing cold front will sweep across Missouri, the winds will shift to the west-northwest and the temperature will fall through the day. We can expect relatively mild conditions over the next 36 hours before another Arctic air mass plunges into the Heartland. Just another winter in the Midwest!

Thursday, December 18, 2008

Transcontinental Express

Developing at the base of a deep, western trough, the latest winter storm brought heavy snows to the Southern California Mountains, southern Nevada desert and Mogollon Rim yesterday. This morning, the storm is moving toward the Four Corners, spreading snow across the Colorado Plateau and Southern Rockies.

By this afternoon, the storm will hitch a ride on the jet stream and move across the Central Plains. Rain, sleet and freezing rain will develop along its path (Kansas-Missouri-Illinois) and heavy snow is forecast for the Upper Midwest. Moving on through the night, this weather system will be in New England by tomorrow morning, ensuring a White Christmas for much of that region.

Of course, most North American storm systems move from west to east, governed by the prevailing winds. The speed of their movement is generally related to their proximity to the jet stream and this one is taking the Transcontinental Express!

Wednesday, December 17, 2008

Owl Nights

We are now facing the long, cold nights of winter, the season of the owl. Equipped with superb vision and hearing and insulated with a dense coat of feathers, the owls rule these frigid nights, oblivious to the conditions. Their prey, primarily mice, voles and cottontails, must stay active to survive and the patient owls are waiting.

This is, in fact, the onset of the breeding season for great horned owls and their hoots will build over the next six weeks. We humans, not naturally designed for this season, retreat to our heated dens; a night in the cold and snow is but a bad dream. But we take solace in the call of the owl, a message that nature's cycle endures and that, in time, spring will arrive.

Monday, December 15, 2008

A Taste of the Arctic

Those of us who live in the Temperate and Tropical Zones cannot truly appreciate the conditions faced by humans and other animals that inhabit the polar regions. This latest Arctic outbreak, triggered by a broad dip in the jet stream, is giving us a taste of life at the Poles. Extreme cold has invaded the Northern Plains, where morning lows hovered at 20-30 degrees F below zero; add in the wind effect and we're talking serious cold!

The development of extreme cold requires a lack of solar heating and limited cloud cover; the latter permits heat to radiate into space and is a common feature of the dry polar climate. In the Arctic, a perpetual night began in mid November and will last until late January; the only warming that they will experience is via southerly winds ahead of polar fronts. In a twist of fate, their relief is at our expense as the intense, Arctic cold is displaced to the south; on the positive side, this polar air is extremely dry and precipitation, in the form of rain, snow or ice, is generally short-lived, moving off with the frontal boundary as the cold, dense air rushes to the south and east.

Looking out from my office window this morning, I watched a snowball moon set behind a flat shelf of snow-white clouds. The temperature was 6 degrees F.

Sunday, December 14, 2008

Windblown Ducks

It was a gray, mild, windy afternoon at Eagle Bluffs yesterday, as a strong southerly flow developed in advance of the next cold front. As usual, there was a large number of wintering ducks at this Missouri floodplain conservation area, southwest of Columbia. Mallards, pintails, gadwalls and green-winged teal were well represented and ring-necked ducks were especially abundant. On the other hand, only a small number of Canada geese were seen and no snows graced the refuge.

The highlight of this visit was the aerial spectacle of the numerous ducks as they attempted to move among the lakes, ponds and sloughs, challenged by the strong southerly winds. Those flying with the wind zoomed effortlessly across the landscape while other flocks, heading against the gale, were blown about, forcing them to veer off course or drop to the surface and wait for the wind to diminish. Many, especially the flight-challenged coots, huddled along the leeward edge of cattails while diving ducks, comfortable in the choppy water, formed rafts on the larger lakes.

To one who looked out across the refuge, the restless ducks, moving in small groups or large flocks, at various angles to the persistent wind, had the appearance of windblown leaves, scattered through the winter sky. Even they, equipped with lean, muscular bodies and instinctual flight skills, were at the mercy of nature's power.

Saturday, December 13, 2008

New England Orogenies

New England has a complex geologic history and, like much of the western U.S., was pieced together by a series of exotic terrains. At the beginning of the Ordovician Period, the east coast of the region was west of what is now the Hudson Valley; then, about 450 million years ago (MYA), an elongated island chain collided with the Northeast coast, adding much of western New England and a large portion of the Canadian Maritime Provinces. This collision initiated the Taconic Orogeny, uplifting a range of mountains from northeast Canada to present-day Virginia.

Fifty million years later, the Avalon Subcontinent, which sat in the northern Iaepetus Ocean, between the North American and European Continents, slammed into New England, adding coastal New England, Nova Scotia and the Avalon Peninsula of Newfoundland; its northeast segment would become northern France and the British Isles. The collision of Avalon with North America triggered the Acadian Orogeny, raising mountains where the Northern Appalachians now stand.

By the end of the Devonian Period, some 350 MYA, these ancestral ranges had nearly eroded to the surface but a new, more extensive Orogeny would soon take place. Throughout the Carboniferous Period, the age of extensive fern forests, giant amphibians and primitive reptiles, the Iaepetus Ocean continued to close, drawing Africa and North America together. The eventual collision of these Continents (320-250 MYA) would produce the Appalachian Orogeny, lifting a continuous chain of mountains from eastern Canada to eastern Oklahoma; these are now known as the Appalachian Mountains (from New England to Alabama) and the Ouachitas (west of the Mississippi Valley). Initially resembling the modern Rockies and Alps, these older mountains have since eroded into lower summits which, except in northern New England, are rounded off and covered by forest.

Thursday, December 11, 2008

Bayou Snow and Northeast Ice

The latest polar plunge, triggered by a dip in the jet stream, was deeper than initially forecast, allowing frigid air to reach the Gulf Coast. At the same time, this advance was rapid and broad, shoving the southern storm eastward rather than northeastward.

Sitting over Mississippi this morning, the powerful storm is raking the Southeast with heavy rains and its "wrap-around" moisture, forced to rise above the entrenched cold, is producing light snow across east Texas and much of Louisiana. The east edge of the polar trough now stretches along the Appalachians and, as the storm moves up the Atlantic Coast, inland snows and coastal rains will be separated by a swath of ice.

Once again, the exact location and extent of the ice storm is difficult to predict but current forecasts suggest crippling conditions will develop from northern Virginia to southern New England. Meteorology is certainly one of the most interesting and frustrating fields of natural science!

Tuesday, December 9, 2008

Dueling Rams

Rocky Mountain bighorn sheep, one of four wild sheep species in western North America, inhabit the Central and Southern Rockies, from Alberta to New Mexico. Grazers, they feed on grasses and forbs, favoring steep, sunny slopes; ewes and their young tend to remain at lower elevations of the foothills and mountains while bachelor herds may be found above timberline during the summer months.

Their annual rut, featuring head-on collisions of the 400-pound rams, peaks in December and is best witnessed in foothill canyons, below 9000 feet. These duels determine breeding rights and, after this seasonal frenzy, all spend the winter in peaceful coexistence. Impregnated females give birth to a single lamb (twins are rare) in late May or June, by which time the rambunctious males have moved to higher ground. The lifespan of the Rocky Mountain bighorn averages 10-12 years but their gregarious lifestyle makes them susceptible to outbreaks of parasitic disease, especially lungworm pneumonia; others die from falls or from predation by humans, mountain lions or coyotes.

There are many places to observe the bighorn rut throughout Colorado; some of the more reliable locations along the Front Range include Waterton Canyon (southwest of Denver), Mueller State Park (west of Colorado Springs), along I-70 (across from Georgetown) and Big Thompson Canyon (U.S.34, west of Loveland). Regardless of where you go, bring warm, layered clothing and binoculars; be aware that dogs are not permitted in Waterton Canyon.

Monday, December 8, 2008

Southern Storm

A storm has developed over the Southern Plains, just ahead of the next polar plunge. As the cold front pushes to the east-southeast, this storm will move northeastward, pulling in plenty of moisture from the Gulf of Mexico.

Rain will develop ahead of the front while heavy snow is forecast for the Upper Midwest. The exact position of the rain-snow line will depend upon the relative positions of the storm and the front; such uncertainty is a challenge and a potential source of embarrassment for meteorologists. Here in Missouri, we are beginning to feel the southerly flow this morning, with a dawn temperature near 40 degrees F; we should remain on the warm side of the system for the brunt of the storm and significant rainfall is forecast for tonight and tomorrow.

The primary benefit of this storm will likely be seen across the Southeast, where a few days of rain should bring some relief from the prolonged drought. Those on the snowy side of the front may not share their appreciation!

Sunday, December 7, 2008

Sunday Driver

When I was a boy, my father used to get angry with "Sunday drivers," those people who drove along in a leisurely fashion, taking in the sights. Now, in middle age, I am one of them.

Today's drive took me southwest of Columbia, looping among farms, across the Missouri River floodplain and past the outer sprawl of this college town. The bright sky, cold and blue, was in stark contrast to the faded greens and browns of the early winter landscape. The usual mix of rural birds, dominated by red-tailed hawks, American kestrels and mourning doves, perched along the roadways and placid farm animals, well fed and content, reflected the serenity of country life. Hoping to spot a flock of snow geese heading south, I saw only an occasional group of Canadas, honking their way above the farmlands.

In truth, it's not easy to take a leisurely drive through the country anymore; drop below forty and you'll soon have a pickup on your bumper. Humans continue to fill the open spaces and the pace of life has increased in concert. The Sunday driver is a threatened species!

Saturday, December 6, 2008

California's Great Valley

Looking at a map of the U.S., one might think that California's Central Valley, on the west coast, and the Chesapeake Bay, on the east, were formed in a similar way; but they would be wrong. While the Chesapeake represents a drowned river valley, the Great Valley of the Golden State is far more complex.

When the Atlantic Ocean began to open, during the Jurassic Period, the west coast of the North American Plate was forced to collide with the Farallon Plate, which underlied what is now the eastern Pacific Ocean; at that time, the west coast of North America was at the longitude of central Utah. As pressure mounted, the Farallon Plate was forced to subduct beneath North America and, as the latter moved westward, a series of exotic terrains and volcanic island arcs were added to the Continent. Between these land masses, seaways were forced to close and, in the process, their oceanic crust was either subducted beneath the growing continent or forced to crumple onto its edge.

The area now covered by California's Great Valley was once one of these entrapped seaways. In fact, it was a deep subduction canyon; to its east, the Farallon plate was melting into the massive batholith of the Sierra Nevada. Over time, this seaway became surrounded by mountainous terrain as the Cascades, Sierra, Coastal Range and Transverse Range formed; sea deposits, volcanic debris and erosional sediments from these highlands gradually filled the sea basin and the surface of the inland sea rose and fell in concert with changes in the Earth's climate. Its connection with the Pacific, once at the latitude of Monterey, shifted northward as the Farallon subduction ended and land shifts along the San Andreas Fault began to reshape the coast.

Eventually filled to the brim with sediments, the massive estuary shrunk to its famous remnant: San Francisco Bay. Throughout the Pleistocene, extensive meltwater lakes covered most of the Valley but, today, reservoirs and water diversion have cut off most of that flow, threatening the health of the Bay and its adjacent wetlands. The Valley itself, once a seaway, has become a flat landscape of desert, irrigated croplands and cities; beneath its surface are miles of sediment.

Friday, December 5, 2008

The Winter Hawk

Having bred and summered across northern Canada and Alaska, rough-legged hawks drift southward through autumn and winter in the U.S.; since they favor open country, these large buteos are best observed across the Great Plains and Intermountain West.

Heavy bodied and long-winged, rough-legged hawks are identified by their appearance and their behavior. Field marks include a light-colored head, dark patches at the bend of each wing and a white tail with a black terminal band; their name reflects prominent feathering of their legs and feet. Despite their size, these raptors often hunt by hovering over their prey and are known for their habit of perching precariously on thin snags or limbs.

Rough-legs feed primarily on lemmings, mice and voles but may feast on the remains of deer or pronghorns that succumb to the winter snows. Come spring, they return to their Arctic and Subarctic haunts where they nest on cliffs or rocky outcrops.

Thursday, December 4, 2008

Colds and the Cold

As the first major blast of winter envelops much of the country, children and adults will be cautioned to avoid "catching cold." After all, the flu and common cold are widespread at this time of year and many assume that cold weather is responsible.

In a way, it is responsible, keeping more people indoors and close together. All of our common viruses are acquired from other persons, either through intimate contact or via droplets spread by sneezing and coughing. The more interaction we have with others, the more likely we are to become infected.

But while prolonged exposure without proper clothing can be harmful (or even fatal), there is little evidence that cold air, itself, increases our risk for infections. Rather, if properly attired, outdoor exercise is just as beneficial in winter as it is during any other season. And beyond its aerobic and stress-reducing benefits, the winter walk takes you away from the viral reservoirs in our homes, offices and shopping malls!

Tuesday, December 2, 2008

The Eastern Quail

Represented by more than 20 subspecies, the northern bobwhite inhabits central and eastern North America, from southern Canada to Mexico; introduced populations are also found in the Pacific Northwest. Despite their broad range, these small quail are subject to periodic die-offs related to severe cold or heavy snow and are threatened by habitat loss in many areas.

Northern bobwhites favor brushlands and immature woodlands where they forage for insects, seeds and berries. Once maintained by occasional wildfires, drought and storms, such habitat has been replaced by suburban sprawl, crop fields, tree farms and mature forest across much of the quail's range. Bobwhites pair off intermittently throughout the spring and summer, raising several broods each year; however, this high reproductive rate is balanced by loss due to weather or predation (fox, weasels, accipiters, owls) and most chicks die within a year. By October, survivors gather in coveys of 20-30 birds, moving and feeding as a group before huddling together on cold winter nights.

As I learned during my boyhood in southern Ohio, bobwhites are more often heard than seen throughout the warmer months, when the distinctive call of the male echoes across fields and farmlands. During the fall and winter, these quail are usually encountered when hikers or dogs spook a covey, causing the members to explode from the brush in all directions.

Monday, December 1, 2008

Winter Arrives

While the winter solstice is still three weeks away, the calendar has flipped to December and the last 24 hours have provided the first real taste of winter. Though periods of cold weather were spaced through the autumn and warm interludes are sure to follow, the cold, darkness, wind and snow of this past day surely marked a transition.

Cold temperatures, day and night, will now rule until March, when the sun begins to reclaim its territory. In the meantime, darkness and quiet will prevail, a survival mode will be adopted and hunters will rule the landscape. And, of course, many humans will retreat to the great indoors and dream of spring.

But those of us who relish the stark beauty of winter will take to the deserted trails and enjoy the quiet solitude of this maligned season. There we will find that our wild neighbors, undaunted by the cold, have no interest in the calendar. For them, retreat is not an option.

Sunday, November 30, 2008

Winter Weed Control

Throughout the colder months, millions of weed seeds cover our flower beds, lawns and fields; millions more lie beneath the thickets and woodlands. Of course, one's definition of "weed" is a bit subjective but even naturalists agree that the seeds of invasive, non-native species are unwelcome components of our ecosystems.

Fortunately, many birds and small mammals consume "weed seeds" and thus play a major role in the control of these plants. In the Midwest, juncos, cardinals, mourning doves, house finches, American goldfinches and a wide variety of sparrows scour the ground for these morsels of energy. Even more are consumed by the huge flocks of starlings, grackles and red-winged blackbirds that roam the winter landscape.

Come spring, there will be plenty left to diversify the foliage but, thanks to the diet of our resident wildlife, their numbers will be kept in check. This natural control is surely preferable to the wholesale use of herbicides, a practice encouraged by the chemical industry!

Saturday, November 29, 2008

Fort Hill State Memorial

The Hopewell Indians, known for their ceremonial earthworks, occupied the Ohio River Valley from 200 BC to 300 AD. Fort Hill State Memorial, in southern Ohio, protects one of their sites and offers a pleasing mix of scenic terrain, broad vistas, geologic features and abundant wildlife.

Located west of Ohio 41, 10.5 miles southwest of Bainbridge, the Memorial stretches along the Baker Creek Gorge and onto a spur ridge of the Appalachian Plateau. Access is provided by eleven miles of trails, which lead through the gorge, along the forested walls and up to the ceremonial fort, 423 feet above the level of the creek. Cliffs of Silurian dolomite line the gorge, where waterfalls and springs produce scenic ice formations during the colder months; in a few areas, this water erosion has carved natural bridges. Higher on the gorge walls, the dolomite gives way to Berea sandstone, Mississippian in age, which caps Fort Hill and other knobs along the valley; the Hopewell used this resistant rock to construct the walls of their fort, which circles the flat summit of the ridge.

Though a popular destination for hikers and naturalists throughout the year, the Memorial is most appealing in winter, when crowds have dispersed and the vistas are broader. Those who visit during the colder months are almost certain to encounter white-tailed deer, ruffed grouse and an excellent variety of woodland birds; turkey vultures and red-tailed hawks often soar above the valley and are best viewed from an overlook at the north edge of the fort.

Friday, November 28, 2008

Feeding Groups

Experienced birders know that woodland birds often move about in mixed flocks and that this feeding behavior is especially common during the colder months. One might hike for some distance without seeing (or hearing) any activity and suddenly come upon a large number of birds, usually composed of multiple species. In like manner, the backyard feeder may stand idle for an hour or so and then suddenly become the focus of a roving flock of residential birds.

In the Midwest and eastern U.S., these "feeding groups" usually contain chickadees, titmice, nuthatches, downy woodpeckers, cardinals and a variety of finches. At times, they may also be followed by ground feeders such as juncos, mourning doves and sparrows. This behavior likely reflects both the benefit of group efforts to locate food and improved protection from predators; more eyes offer better detection and the large number of moving targets may confuse the hunter.

Avid birders know that such feeding flocks offer immediate gratification (in terms of number of species) and often attract uncommon birds that are visiting the area. For example, a mixed group of juncos, song sparrows and white-throated sparrows may also harbor a fox or Harris' sparrow. Though most of us enjoy watching our common residents, the possibility of encountering an unexpected guest is always an underlying motivation!

Thursday, November 27, 2008

On Behalf of all Species

Those of us who care about wildlife and the health of natural ecosystems know that they are under constant threat from the forces of development, pollution and exploitation. We also understand that the only way to sustain the biologic diversity of this planet is to protect wilderness, in all of its forms. Vast and undisturbed forests, deserts, wetlands, prairies and marine ecosystems are vital to the welfare of Earth's species, including humans.

On this day of Thanksgiving, it seems appropriate to acknowledge the work of those many individuals and organizations across this globe that are devoted to wildlife conservation and open space protection; some of these groups are listed in the right column of this blog. On behalf of the varied creatures that inhabit our planet, I thank them for their efforts and urge others to support them.

Wednesday, November 26, 2008

Curiosity and Fear

Man is a curious creature. Were he not, our species would have perished in Africa, the victim of overcrowding, malnutrition and disease. Curiosity, the stimulus for adventure and exploration, has take us across the globe and into space. At each step along the way, curiosity had to conquer fear.

The advance of human culture has also been dependent upon our curiosity, which was (and is) the essential ingredient for the scientific revolution. The desire to understand the "how and why" of our complex Universe (and of our place in it) has led to a long string of scientific theories and discoveries. Once again, the steps involved in this process necessitated the courage and curiosity to overcome fear and to take risks.

The knowledge derived from exploration and discovery can induce other fears. Some humans deal with these fears by ignoring or rejecting science-based knowledge. They hide within their simplified view of this world; for them, faith trumps science and curiosity tempts fate. Somehow, humans must ensure that our natural curiosity is sustained and that fear, of real or imagined threats, does not impede our progress.

Monday, November 24, 2008

Bright Lights

For those who care to look, there are an endless number of natural spectacles on this planet. But sometimes, it is our vantage point in the Universe that yields the visual splendor.

This week, Jupiter and Venus close in on one another in the southwest sky; this spectacular rendezvous is best observed just after dusk. Their pairing, of course, is just a temporary illusion, produced by our current point of view. In fact, Jupiter, though much larger, is five times further from Earth than is Venus; on the other hand, Venus, orbiting much closer to the sun, is far brighter than Jupiter (both, of course, are merely reflecting light from the sun).

Natural spectacles on Earth make us feel part of a complex yet beautiful ecosystem. Those in the night sky induce wonder and humility. Our magnificent planet is, after all, just another bright light in a vast sea of darkness.

Saturday, November 22, 2008

A Cloudless Sky

Over the past decade, I have made numerous road trips between Colorado and Missouri; until today, I cannot recall one in which the entire 800-mile drive was made under a cloudless sky. Becoming aware of this fact during the trip, I started looking for even a hint of clouds on distant horizons; alas, none were seen.

High pressure controlled the entire Great Plains province today, shunting any Pacific moisture into Canada and blocking any flow from the Gulf of Mexico. Under such conditions, the air within the dome sinks, further compressing and drying the air. Since the formation of clouds and showers requires lift, atmospheric conditions within the high pressure dome negate any chance of their development.

In addition to the cloudless sky, evidence of the low humidity was made evident by the rapid evaporation of power plant steam and by the short contrails of commercial jets. Under more typical conditions, we see the long exhaust trails of these planes crisscrossing the sky, often distorted by the effects of high altitude winds; today, their linear exhaust clouds rapidly disappeared within seconds of their production.

As one might expect, persistent high pressure domes are found in many desert regions and can lead to prolonged drought in other areas. These domes are also characterized by light surface winds which, combined with the sinking air, exacerbate air pollution in urban centers.

Friday, November 21, 2008

November along the South Platte

It was cool and sunny along the South Platte River this afternoon, marred only by a moderate, upslope haze. The annual waterfowl surge is well underway with a wide variety of ducks on the river and floodplain lakes; buffleheads and green-winged teal were especially common today. Other water birds included pied-billed grebes, American coot, ring-billed gulls, great blue herons and a few killdeer; double crested cormorants, common here during the warmer months, have apparently departed for the south.

Though I didn't spot any bald eagles today, several red-tailed hawks and American kestrels represented the raptors. Flocks of Canada geese, entering their peak season along the Front Range, provided a background chorus while belted kingfishers chattered along the river. As one might expect on a mid day visit, mammals were seldom encountered, represented only by the fox squirrels and a lone muskrat.

Woodland birds were active on this cool afternoon; magpies, northern flickers, downy woodpeckers, blue jays, chickadees and song sparrows were most common. But the highlight of this visit was a Harris' sparrow, feeding in thickets at the edge of a lake. Though not rare along the Front Range, their presence is erratic and we naturalists always welcome the unexpected. After all, it's the unpredictability of nature that keeps most of us engaged.

Townsend's Solitaire

We have owned our Littleton, Colorado, farm since 1990 and, each winter, a Townsend's solitaire has taken up residence from November through March. Attracted by the large, prolific juniper trees, the solitaire is highly territorial, defending his supply of berries from other solitaires and, unsuccessfully, from the larger robins that also enjoy this bounty.

Townsend's solitaires are gray, streamlined thrushes with a prominent white eye ring and buff-colored wing patches; they are mid-sized between blue birds and robins. Throughout the warmer months, they inhabit coniferous forests of the foothills and mountains where they are usually seen alone, flycatching from a dead snag or treetop. Solitaires nest on the ground, choosing a protected site beneath a shrub, fallen tree or rock overhang; four eggs are typically produced and, as with most other thrushes, both parents tend to the nestlings.

As cold nights begin to eliminate their insect prey, these birds switch to a diet of juniper berries and many descend to lower elevations; the majority choose protected, foothill canyons while some, like our visitor, move onto the adjacent Piedmont; west of the Divide, many winter in desert regions of the Colorado Plateau or Great Basin. Occasionally, adventurous solitaires wander far to the east, turning up in the Great Lakes region or even in New England.

Thursday, November 20, 2008

Oceanic Islands

The islands that we observe in Earth's oceans today were formed by one of three processes: flooding, volcanism or rifting; in some cases, more than one process was involved. Most of the islands near Continental coasts are merely high ground on the continental shelf, cut off from the mainland when sea level rose after the Pleistocene glaciers retreated; Great Britain, Ireland, Newfoundland, Long Island, Sri Lanka and Tasmania are all examples of such islands.

Most oceanic islands are volcanic in origin, having developed in one of three ways. Some develop by volcanism along a spreading ridge, where plates are moving apart and new ocean crust is forming; Iceland and the Azores are prime examples (the Azores occur at a site where three tectonic plates, North American, Eurasian and African, are pulling apart). Hotspot islands, such as the Hawaiian, Galapagos and Cape Verde Islands have developed above a mantle plume, often far from a plate margin. Finally, volcanic island chains form along subduction zones where one plate is being forced beneath another; the Aleutians, Japan, outer Indonesian islands, the Philippines, the Solomon Islands, New Zealand and the eastern Caribbean chain are all examples of subduction island arcs. For every volcanic island that breaks the surface, there are hundreds of "seamounts" that stopped forming at an earlier stage.

The rifting of small land masses from larger, continental cratons has been occurring throughout our planet's history. Madagascar is the classic example; having separated from Africa during the breakup of Pangea, it attached to both Antarctica and India before anchoring off Africa once again. The Falkland Islands, once a piece of South Africa, moved off with South America as the southern Atlantic opened and Vancouver Island, once a slice of Australia, is now prime Canadian real estate. And, in the "near future" (geologically speaking), Southern California and the Baja will become an island in the Pacific.

Reality Check

Like a massive atmospheric bowling ball, a cold dome of high pressure has rolled into the Northern Plains and our brief summer has been squashed back toward the Southwest. We sit at 28 degrees F this morning and will reach a projected high of 35 this afternoon; that's 30 degrees colder than yesterday and more than 40 degrees colder than the high of two days ago.

Since the center of this frigid dome is still up in Alberta, its surrounding, clockwise winds are coming in from the east, producing upslope conditions along the Colorado Front Range; snow showers, fog and freezing drizzle are forecast for much of the day. Suddenly, it feels like November once again.

Fortunately, this dip in the jet stream is expected to flatten out and the cold air will soon be shunted off to the east. More seasonable conditions will return for the coming week, with highs in the 50s and lows in the 30s. But alas, our fling with summer has ended.

Wednesday, November 19, 2008

Golden Gate Canyon

The promise of another mild, sunny day sent me off to Golden Gate Canyon State Park, in the foothills northwest of Golden, Colorado. Known for its scenic granite outcrops, abundant wildlife and fabulous trail network, the Park is a popular destination for Front Range naturalists and hikers. Among its resident wildlife are black bear, mountain lions, mule deer and wintering elk.

This morning, I elected to take the Horseshoe Trail, for a gradual, 1.8 mile climb to Frazier Meadow. Rock outcrops just short of the meadow offer scenic panoramas of the Park and are a great spot for a picnic lunch; Mt. Tremont, the centerpiece of Golden Gate, looms to the northwest. On today's hike, I saw the usual mix of foothill birds (mountain chickadees, Townsend's solitaires, Steller's jays, pygmy nuthatches and pine siskins), noisy red squirrels and a few mule deer; no bears or mountain lions today! From the meadow, I was also treated to the flight of a golden eagle as it soared above the Ralston Creek Valley.

From Colorado 93, just north of Golden, turn west on Golden Gate Canyon Road; 13 miles of winding pavement will take you to the Park's Visitor Center. A day-use fee is charged (currently $6 per vehicle).

Tuesday, November 18, 2008

Summer in November

It feels like summer along the Colorado Front Range today, with high temperatures expected to reach the upper seventies. But, if you open your eyes, you will find that it is still November. The trees and shrubs are mostly leafless and those leaves that still flutter in the breeze have lost their October glory. Most noticeable is the lighting, the effect of the low, seasonal sun angle, which produces long shadows and less intense sunlight.

For those interested enough to notice, the summer songbirds are absent and a mix of winter visitors and permanent residents feed in the thickets and woodlands. Here on our Littleton farm, there are no house wrens buzzing about the brush pile or colorful orioles moving among the mulberries; rather, juncos have arrived to join the chickadees, house finches, flickers, magpies and other regulars. Canada geese, much more common during the colder months, are another sign of the season, their noisy flocks moving about the area from dawn to dusk.

This brief heat wave, a common occurrence along the Front Range, is due to two factors. The current jet stream pattern has produced a high pressure ridge over the western U.S., allowing warm air to move up from the Desert Southwest. Augmenting this effect, the southwest winds descend on the east side of the Continental Divide; as air is forced to descend, it compresses, dries out and heats up. These chinook winds produce periods of mild weather throughout the winter and cause heavy snows to melt rapidly (unlike the persistent snowpack of the Upper Midwest and Northeast). Lest I dwell too much on the fabulous Colorado climate, it is important to note that the ridge is expected to break down within two days; the jet stream will dip and cold, Canadian air will pour south across the region.

Monday, November 17, 2008

The Osage Orange

It must have been a good year for osage orange trees in eastern Kansas. Their large, globular fruit seems to be especially abundant in the tangled, leafless trees that edge the cropfields and pastures along I-70. Native to the Red River Valley of Texas and Oklahoma, the osage orange was found to be an ideal tree for windbreaks and fence rows and is thus widely planted on the Great Plains; hard, rot resistant wood and interlacing, thorny branches provided natural fencing for early ranchers. The tree, a member of the mulberry family, is also planted as an ornamental in other parts of the country; since it is both drought tolerant and prolific, the osage orange readily naturalizes and can become a nuisance.

The fruit, also known as a hedge apple, develops with a green, nodular surface and remains on the tree until late October or November; by that time, it has taken on a faded yellow color and, adorning the bare woodlands, seems to be a harbinger of the coming holidays. The large globes, which contain 200 or more seeds, are nearly inedible due to their milky, acidic juice and tough, fibrous pulp; the seeds themselves are eaten by squirrels and mice.

Arborists caution homeowners to choose a male tree for ornamental plantings; the abundant fruit, borne solely on the female trees, collects on the ground in rotting masses. I personally recall using them during my boyhood in Cincinnati; we called them "stink bombs" and launched them at imaginary invaders from the safety of our tree fort.

Sunday, November 16, 2008

America's Till Plain

Driving across central Illinois, one encounters one of the flattest landscapes in the eastern U.S.; it is a classic till plain. Plowed flat by the Pleistocene glaciers, this region was also covered by a thick veneer of till (pulverized rock and organic debris) as the ice sheets retreated toward Canada. In concert, meltwater streams began to mold the plain, draining toward the Ohio and Mississippi Rivers; since they were eroding soft, loosely compacted deposits, these streams meandered, creating broad, shallow valleys that give little relief to the flat plain.

Before white settlers arrived in the Midwest, this vast till plain was covered by tallgrass prairie. Periodic drought, wildfires, high winds and the grazing of massive bison herds maintained the prairie and woodlands were limited to the stream valleys. Today, trees also rise along fence lines and throughout the numerous towns and cities that dot the landscape; the tallgrass of the Prairie State, while protected or reestablished in some areas, has given way to the American Cornbelt.

Illinois lies at the heart of North America's till plain, a geophysical province that stretches from central Ohio to the eastern Dakotas and northward into Canada. The Continental Glaciers molded the landscape of the Midwest but, more importantly, produced the thick, rich soil that feeds much of the world's population.

Saturday, November 15, 2008

A Day for Crows

A drive back to Ohio in mid autumn can be a pleasant experience; not this time! A storm system, centered over the Great Lakes, brought wind and cold rain to the Midwest today, producing gray skies, low clouds and a damp landscape. Dead leaves, brown or faded yellow, clung to the winterized trees, corn stubble withered in the steady rain and shallow pools dotted the grassy fields. Wild creatures, taking cover in these raw conditions, were few and far between, represented by an occasional red-tailed hawk along the highway, a group of wild turkeys in the Wabash Valley and a lone coyote in southeast Indiana; a notable exception was the large number of crows.

Crows are oblivious to the vagaries of Midwest weather. Today, small flocks scavenged along the Interstate, scoured the crop fields or gathered in the bare timber. Raucous and aggressive, these birds are often maligned but one must admire their fortitude and perseverance. These traits, after all, have ensured their success in a fickle and competitive environment.

Friday, November 14, 2008

Unnatural Lines

When we get the opportunity to view the Earth from aircraft or study photos from space, we notice that something is missing. Having studied geography throughout our years in school, we expect to see boundaries around countries, provinces, states and counties. After all, those lines define our allegiances and play a major role in our own self image.

Nature, of course, pays no attention to these lines. They do not impede migrations, stream flow or weather patterns. Storms and earthquakes move across them and they often have no correlation with natural, geophysical boundaries. Neither do those lines offer protection from the global effects of climate change or pollution.

These human boundaries, the supreme expression of our tribalism, are the equivalent of territorial behavior in other mammals. And while they may serve a purpose in social organization, they foster nationalism, discrimination, mistrust and war. This provincial mindset is also a major obstacle to resolving global issues and to our efforts to eliminate disease, poverty and hunger. Perhaps man will eventually evolve beyond the need for these lines; John Lennon asked us to imagine such a planet.

Thursday, November 13, 2008

The Walrus and our Climate

The common ancestor of pinnipeds diverged from terrestrial bears during the Miocene Period, about 20-25 million years ago. Today, these semiaquatic mammals are represented by three families: true seals, eared seals (sea lions) and walruses.

Once composed of numerous species inhabiting tropical, temperate and arctic life zones, the walrus family has two surviving members, the Atlantic and Pacific walruses; both are Arctic residents. The Atlantic walrus was once found as far south as Cape Cod but is now restricted to to the Arctic of northeastern Canada, Greenland and northwest Russia. The Pacific walrus, a bit larger and much more numerous, summers on and along the Chukchi and Beaufort Seas but winters south of the Bering Strait; male groups may remain in the more southern areas throughout the year.

Both species rely on ice flows, rocky islands and isolated beaches to "haul out" in order to rest, warm up or to give birth. Walruses breed in late winter and a single calf is born in spring of the following year (twins are very rare); a quarter of this prolonged gestation results from delayed implantation of the embryo. Females nurse their young for up to two years and are thus impregnated no more often than every 2-3 years. Though their life span may reach 50 years, this low birth rate makes the walrus population especially vulnerable to external forces such as hunting pressure and alterations in their habitat.

The warming of Earth's climate is sure to affect the welfare of these colonial creatures. Though hunting restrictions have led to a rebound in the world population (currently estimated at 250,000, of which 80% are Pacific walruses), global warming has already had an impact on Arctic ice formation and may adversely affect the bivalve mollusks on which these pinnipeds feed. In addition, a reduction of their haul-out options may make them more vulnerable to predators (killer whales, polar bears and humans), especially during the calving period. Of course, time will tell.

Tuesday, November 11, 2008

Humans in the Americas

Though we evolved in Africa some 125,000 years ago, humans would not reach the Americas for more than 100,000 years. Man spread into Australia by 60,000 years ago and occupied the Mediterranean region about 50,000 years ago but would not set foot in North America until the peak of the Wisconsin glaciation, some 20,000 years ago.

The great majority of human migrants reached the Americas via the Bering Land bridge, which remained open through most of the late Pleistocene; however, DNA evidence suggests that some of these original inhabitants arrived from Europe after hunting their way along the southern edge of the North Atlantic ice shelf. Those crossing from Asia bypassed the North American glaciers via two routes; some (perhaps most) spread southward along the Pacific coast while others followed herds of mammoths and bison through an ice-free corridor east of the Rocky Mountains. Most archaeological evidence indicates that man was south of the glaciated areas by 15,000 years ago and had spread throughout North and South American by the end of the Pleistocene (10,000 years ago); by 7000 years ago, humans had crossed the Florida Straits and were living in Cuba.

As elsewhere, early Americans were nomadic and permanent settlements did not appear until the Holocene (10,000 years ago). Among the more famous cultures and civilizations to rise in the Americas were the Mayans of Central America (2000 BC to 1550 AD), the Hopewell mound builders of the Ohio River Valley (200 BC to 300 AD), the Fremont People of the Great Basin (600-1200 AD), the Anasazi cliff dwellers of the Colorado Plateau (500-1300 AD), the Aztecs of Mexico (1100-1550 AD) and the Incas of Peru-Bolivia-Chile (1400-1550 AD).

Monday, November 10, 2008

First Snows

Walking to work on this cold, November morning, my attention was drawn to the distant, unmistakable call of snow geese. Faint at first, the high-pitched clamour grew louder but they were difficult to find among the high clouds in the predawn light. Suddenly, I saw them, a wavering double-V of migrants, angling to the southeast.

Long a favorite of mine and an inspiration for many naturalists, snow geese are among the last migrants of fall and the first to head north in the spring. Here in Missouri, their numbers will build through mid December but, eventually, most will move on to wetlands along the Gulf Coast and lower Mississippi Valley. By February, flocks will travel north once again, destined for breeding grounds on the Arctic tundra.

More that almost any other species, migrant geese stir the soul of man. Moving high overhead, their vocal flocks symbolize both freedom and determination. If only we could give up our daily troubles and share their adventure!

Sunday, November 9, 2008

Hurricane Paloma

The development of a hurricane requires warm ocean water, a hot, humid environment and light, upper-level winds. During the peak of the Atlantic Hurricane Season, which extends from June through mid November, most storms develop from tropical waves that move westward off the coast of Africa. However, early and late in the season, these storms usually form over the warm waters of the Caribbean Sea or Gulf of Mexico; Hurricane Paloma offers a classic example.

After developing in the western Caribbean, Paloma began to drift to the northeast under the influence of an approaching cold front. Moving across open waters and beneath a calm upper atmosphere, the storm strengthened to a Category 4 Hurricane as it ravaged the Cayman Islands and headed for Cuba. Fortunately, just off the southern coast of Cuba, the storm encountered the strong upper level winds of the advancing front; combined with the effects of the island's mountainous terrain, these shearing winds disrupted the storm's crucial symmetry and it rapidly weakened to a minor, Category 1 Hurricane.

Paloma is expected to emerge from the north coast of Cuba as a tropical storm and to move off rapidly to the northeast. Of course, any slowing of its forward motion could allow the storm to redevelop but, as of now, the strong upper-level winds will likely prevent any strengthening and Paloma will die in the open Atlantic.

Saturday, November 8, 2008

Winter Songsters

Once the summer residents head south and cold, gray weather invades the Heartland, the sound of birdsong nearly disappears until late February. Peeps and twitters rise from the thickets, the raucous calls of jays, crows and woodpeckers ring through the woodlands, the yank of nuthatches echo through our yards, the hoot of owls greet the dusk and the clamour of geese stirs the soul. But only a few birds bring a cheerful tune to our bleak winter days.

Chickadees, undaunted by the cold and snow, sing their way through the season, keeping hope alive for the rest of us. White-throated sparrows, having summered in Canada, are perfectly comfortable in our winter weather; though their distinctive tune is shorter and less intense than it will be next spring, they refuse to spend the season in silence. Finally, the Carolina wren, while looking out of place in the snowy landscape, is feisty enough to sing any time he wants: winter be damned!

Friday, November 7, 2008

Pinwheel on the Plains

A potent winter storm has been lumbering across the Northern Plains over the past two days. Like a giant pinwheel, the central low pressure is surrounded by strong, counter-clockwise winds; pulling in warm, moist air ahead of the front, these winds force the air to rise and cool as it moves west, dropping heavy snow across the Dakotas. On the west side of the storm, which is now centered along the Minnesota-Wisconsin border, strong, north winds are dragging frigid air down from Canada and, combined with the heavy snow, are producing blizzard conditions across the northern High Plains.

Here in Missouri, on the south edge of the storm, the winds are from the west, ushering in cool, cloudy weather and occasional showers. As the storm moves into the Great Lakes, our clouds will disperse but a steady, northwest wind will augment the chill for the next few days. It is, after all, November and winter is gaining control.

Thursday, November 6, 2008

The Nature of Racism

Man evolved in East Africa about 125,000 years ago and, for the first 70,000 years of our existence, virtually all humans were dark-skinned; this trait offered protection from the intense, tropical sun, which characterized their habitat across Africa, southern Asia and Australia. About 50,000 years ago, man began to spread northward, entering temperate regions where solar radiation was reduced by the seasonal change of the sun angle. As has occured in other species, variability in skin pigmentation began to develop among human populations, reflecting an adaptation to the environment via the process of natural selection. Today, a spectrum of skin coloration characterizes our species and further variation will occur due to gene mixing through inter-racial marriages.

Unfortunately, this single human trait, though totally unrelated to other human features and capabilities, has become a rationale for discrimination and persecution. Rooted in ignorance, such beliefs are ingrained in children at a young age and fostered by one's political, cultural and religious environment. Uneducated humans, exposed to the influence of religious fundamentalists and other hate groups, develop racist views; this process is especially common in social groups where science is discredited. By accepting creationism and rejecting evolution, such groups find it easy to buy into the concept of racial distinctions; God surely designed a superior race in his own image!

Hopefully, the election of President Obama will put another nail in the coffin of racism. But until we evolve beyond the ignorance of our ancestors, this ugly mindset will remain a part of human society.

Tuesday, November 4, 2008

Nature and the Election

As an Independent, I am a social liberal and a fiscal conservative. But, as an environmentalist, I usually support the Democrats and, in this election, there's too much at stake not to do so once again.

Of course, both political parties claim to be concerned about the environment but, in my experience, their reasons and solutions differ dramatically. Conservative Republicans view conservation in the context of outdoor recreation. Favoring industry, development and personal freedom over the protection of natural ecosystems, they often minimize the impact of human culture on the environment. They favor access over wilderness, new roads over mass transit and exploitation over conservation. To them, concerns about global warming, endangered species and habitat destruction reflect the bias of a liberal media. Governed by capitalist principles and a religious mindset, they view the natural world as God's gift to man, his chosen species and the pinnacle of his creation.

After eight years of enduring the Bush Administration, nature and the civilized world are in desperate need of a change. Let's hope the majority agree.

Monday, November 3, 2008

Mid Plate Earthquakes

Most earthquakes originate along the edge of the tectonic plates where compression, friction or subduction occur. Other common sites are along rift valleys or mountain ranges where buried fault lines are especially numerous.

But, on occasion, earthquakes strike in areas where there is little surface evidence of past or recent tectonic activity. Tremors may strike vast plains, rolling farmlands or flat lake country. In such cases, the quake originates deep below the surface, in the basement rock of the tectonic plate, and usually reflects the presence of an old suture line or aborted rift zone. Since covered by thick layers of sedimentary rock and surface deposits, these deep faults, often quiescent for thousands or millions of years, suddenly shift due to pressure change within the plate.

Almost all of western North America was pieced together by small plates and exotic terrains that were welded to the primary North American Plate. These numerous suture lines remain a common source of earthquakes and, as the Great Basin continues to stretch, the rifting of these old margins will intensify the tectonic activity. Other, more stable regions of the Continents once formed and reformed in a similar fashion and their long-dormant sutures are prone to an occasional rupture.

While the risk for earthquakes varies widely across the globe, no region is immune. We all live in earthquake zones!

Sunday, November 2, 2008

Smithville Lake

Smithville Lake is a large reservoir north of Kansas City, Missouri. Stretching north to south above the east wall of the Missouri River Valley, the Lake and its surrounding wetlands are a magnet for migratory waterfowl and early November is an excellent time to visit. Access to the area is via U.S. 169 (north of I-435), on the west side of the Lake, or from Missouri 92 which passes south of the reservoir; the Visitor Center is adjacent to the Dam on Route DD, which loops between the above highways.

Migrant ducks are peaking by November; rafts of diving ducks (redheads, ring-necks, scaup, common goldeneyes, buffleheads, ruddys, canvasbacks and mergansers) gather on deeper waters near the dam while surface feeders (mallards, wigeon, gadwall, shovelers and coot) favor the backwater shallows; the former are often joined by a variety of loons, grebes, gulls and terns though pied-billed grebes prefer the shallower waters. Bald eagles are common here throughout the colder months, peregrine falcons follow the migrant waterfowl and ospreys fish on the lake during their spring and fall migrations. Large flocks of double-crested cormorants are also attracted to the reservoir and often roost in drowned trees north of the Route W bridge.

American white pelicans rest and feed along the shorelines and, as autumn progresses, large flocks of Canada and snow geese visit the reservoir. In addition, birders will find an excellent variety of raptors, game birds and upland songbirds in the woodlands, wetlands and fields that surround the lake.

Saturday, November 1, 2008

November in Missouri

Despite its reputation for cold, gray, blustery days, November offers its fair share of pleasant weather in Missouri. In most years, the warm afternoons and cool nights of October spill into the first half of the month and persistent cold is unlikely to develop until December.

Beyond the fair conditions, November offers some significant attractions for naturalists. Though the autumn colors are fading, the crisp air and dry trails make conditions ideal for hiking. Yet, perhaps in anticipation of the coming winter, the crowds begin to diminish and the opportunity for solitude increases through the month. At the same time, wildlife, stirred by the autumn chill, become more active (and watchable) and the migration of waterfowl is peaking across the State.

For all of these reasons, November is a great month for outdoor exploration in Missouri. Then again, the other eleven are as well!

Friday, October 31, 2008

The Halloween Hunters

As if on cue, the distinctive call of a barred owl pierced the predawn darkness this Halloween morning. Owls, after all, are the quintessential Halloween birds: spooky, nocturnal predators. More often heard than seen, the night-hunting owls are recognized by their deep hoots, hissing rants, tremulous calls and chilling screams. When we hear them, images from black and white horror movies flash through our minds.

Of course, owls are of no threat to humans and play an important role in the control of mice, cottontails and other small mammals. But our species, ill-equipped to function in the dark, has long feared the mysterious creatures that rule the night. We sometimes find the remnants of their kill, body parts or a bloodied scene, the next morning and can only imagine the terror of the hapless victim.

So, after the witches and pirates leave your porch this evening, go out to listen for our Halloween hunters. Their dark, cold season is just beginning.

Thursday, October 30, 2008

Pleistocene Land Bridges

During the Pleistocene "Ice Age," which began 2 million years ago, four major glaciations occurred, separated by warm interglacial periods; whether the Pleistocene ended 10,000 years ago or if the current Holocene Period is just another interglacial phase remains a subject of debate among climatologists.

The most recent Pleistocene glaciation, the Wisconsin, began 70,000 years ago; at its peak expansion, about 23,000 years ago, one third of Earth's land mass was covered with ice. Since there is a finite amount of water on our planet, this extensive ice formation was accompanied by a dramatic fall in sea level; at the peak of the Wisconsin glaciation, sea level was 400 feet lower than it is today and the coastline of North America was 100 miles east of New York City. Elsewhere on the planet, land bridges opened between continents and islands, allowing humans and other animals to migrate across the globe.

DNA evidence suggests that the low sea level of the Pleistocene permitted man to walk from East Africa to Yemen, perhaps as early as 70,000 years ago, triggering the colonization of southern Asia. The major islands of the Indonesian Archipelago became a broad peninsula, allowing man to approach Australia by 65,000 years ago; he managed to cross the remaining ocean barrier (perhaps by accident) within 5000 years and then reached Tasmania via another land bridge. About 50,000 years ago, humans colonized Japan after migrating across a land bridge that extended eastward from the Asian coast. Finally, the most famous Pleistocene land bridge, Beringia, connected Siberia and Alaska, allowing humans, bison and mammoths to reach North America and, in the reverse direction, horses to enter Asia.

Wednesday, October 29, 2008

Children and Conservation

Children are the hope of mankind. They are the most compelling reason to end war, combat discrimination, eliminate suffering and foster freedom across the globe. They also represent our only opportunity to pass the conservation ethic to future generations.

Born into a world of advancing technology, today's children are enticed by an array of gadgets that offer instant messaging, social networking, online information and global communication. They are entertained by reality shows, computer games and the world wide web. Solitude is a lost art and an interest in nature is a potential victim of their lifestyle.

It is thus especially important that we introduce young children to the joy and wonders of nature. Impressions made in early childhood last a lifetime and a child's interest in plants and animals will instill a curiosity that carries through adulthood. So take your kids and grand kids to the nature preserves. Let them see mountains, deserts and seascapes. Buy them binoculars and telescopes. Introduce them to mushrooms, frogs and bighorn sheep. Talk about pollution, glaciers and dinosaurs. Our natural heritage will soon be in their hands; it must first live in their souls.

Monday, October 27, 2008

Midwest Wind Tunnel

Northwest winds raked the Midwest yesterday afternoon and continued into the night. Produced by a strong pressure gradient between high pressure over Colorado and low pressure over Ontario, the winds swept cold, dry, Canadian air into the Heartland. This morning, many Midwestern cities are below freezing for the first time this season; here in Columbia, we missed by two degrees.

As the system moves eastward, counterclockwise winds around the low pressure center will sweep across the Great Lakes, picking up moisture and dumping lake-effect snows on the higher terrain south and east of the Lakes. Meanwhile, the Great Plains and Midwest will be recovering from the damage wrought by this Canadian Express; winds gusted to 65 mph in some areas, toppling trees, tossing trailers and knocking out power. Just a preview of events to come!

Sunday, October 26, 2008

Rifts, Geography and Time

Over its 4.6 billion-year history, the surface of our planet has been steadily changing; the size, shape and position of our oceans and continents are in a constant state of flux. A map of the Earth today bears little resemblance to the surface features 200 million years ago and will be just as useless in the distant future.

The motion of the tectonic plates that form the crust of our planet is governed by the opening and closing of oceans; in the former case, a land mass rifts apart while, in the latter, continents are forced to collide and fuse. During the Permian Period, 250 million years ago, Earth's land masses had coalesced into the mega-continent of Pangea. Fifty million years later, the Tethys Sea began to open, rifting Pangea from east to west and separating Laurasia (the northern continents) from Gondwana (the southern continents). About 150 million years ago, the Atlantic opened, rifting these super-continents from north to south and, over the next 100 million years, arms of the Atlantic, Indian and Pacific oceans cut apart Laurasia and Gondwana, producing the map that we see today.

But rifting continues. The Red Sea-East African Rift complex began to develop 40 million years ago and will eventually open a seaway through Africa. Rifting on the east and west sides of Greenland occurred 30 million years ago, producing northern arms of the Atlantic and breaking up a land bridge that had connected Europe and North America. The Gulf of Aden and Rio Grande Rifts began to open 10 million years ago, the Gulf of California opened 5 million years ago and the Lake Baikal Rift began to develop 2.5 million years ago; the latter will eventually connect with the Arctic Ocean, cutting Russia in half. In like manner, further rifting across the Great Basin of North America will merge with the Gulf of California Rift, flooding the Intermountain West with an arm of the Pacific.

Saturday, October 25, 2008

The Big Chill

Yesterday's rain was the leading edge of a cold front that has pushed on to the southeast. High pressure behind the front has brought cold temperatures across the entire country; only South Florida and the extreme Southwest will be spared this first major cold wave of the season.

On my predawn walk to work this morning, a crescent moon hung in the eastern sky, Sirius sparkled to the south and Orion, our winter companion, loomed to the southwest; the temperature was 36 degrees F. Lows in the forties are as far south as Mississippi and, as this air mass is reinforced by a second cold front, lake-effect snows will develop along the Great Lakes.

Winter has won this round but the battle with summer continues and warmer air is expected by later in the week. But the tide has clearly turned and the slide toward winter will gain momentum. Just ask the juncos and white-throated sparrows that now feed in our thickets and woodlots; they've arrived from Canada to enjoy our Midwestern winter and will stick around until April.

Friday, October 24, 2008

Water Therapy

Water has a calming effect on most people. Waterscapes, from pounding surf to placid lakes to whitewater streams, are popular destinations for recreation and humans have long established settlements along shores and rivers. While the latter served a number of practical needs (water, food, transportation), man has undoubtedly received a great deal of comfort and inspiration from nearby waterways.

After all, life evolved in the sea some 3.6 billion years ago and did not emerge onto land until 400 million years ago. We, like other life forms, are composed primarily of water and humans spend the first nine months of their life floating in a uterine pool. We can't survive more than a few days without this precious substance and its presence or absence has governed man's colonization of the planet.

Even those of us who prefer dry climates relish an escape to the beach or mountains now and then. Water is entrenched in our souls and the sight, sound and feel of it calm our troubled minds.

Thursday, October 23, 2008

Human Nature

We humans, like other animals, are products of our genes and everything that we do in our lives is devoted, in some way, to their preservation. While this commitment is easy to appreciate in simple organisms, our complex lives, governed by intellect and emotion, shroud this basic, underlying imperative.

Our brain power supplants the instinctual behavior of other creatures. We think, reason, love, worry, ponder and anticipate. We wonder. We are curious. We communicate, debate, create, explore, judge and plan for the future. But, beneath this veneer of activity, thought and emotion, is the primordial drive to protect and sustain our genetic heritage.

We learn to survive. We work, beg or steal. We use our skills to provide for ourselves and our offspring or to con others for those resources. We may be kind or cruel. We may be generous or self-centered. We may be tolerant or judgmental. We may put our faith in gods or in science. We may expect to live forever or accept the temporal nature of our lives. In the end, our motivation is the same.

Wednesday, October 22, 2008

Dusk on the Beach

One evening last week, my wife and I walked out to the beach to watch the sunset on the Gulf of Mexico. Though we missed the main event, a blaze of orange ignited the western horizon, reflecting in the calm waters of the Gulf. As the intense color waned, the sky faded from pale blue to a metal gray and Venus, the "Evening Star" appeared in the western sky; Jupiter, less bright but no less inspiring, glowed high to the southwest.

Catching the last reflections from the evening sky, the Gulf became a sheet of gray and low waves, backlit by the fading dusk, moved toward the shore like a series of black bars. Ghost crabs scurried across the beach while the last flocks of gulls and egrets passed overhead, on their way to nocturnal roosts. The soft break of waves, disrupted only by the occasional squawk of a night heron, enhanced the serenity.

But just as the final glimmer of sunlight retreated below the horizon, something thrashed in the shallows. A ray or sand shark had apparently struck its target; the night hunters had begun their shift. It was time for us humans, ill equipped to function in the dark, to retreat to the condo.

Tuesday, October 21, 2008

Ghost Crabs

Residents of sandy beaches, ghost crabs live in burrows that they dig along the seaward edge of the dune line. These burrows are up to four feet deep and provide a cool, wet retreat where the crabs escape predators and keep their gills moist and functional. Though they are most active from dusk to dawn, scouring the beach for food and bathing their gills in the surf, ghost crabs are often encountered during the day and are easily identified by their pale color and prominent, dark eyes; the latter, which sit atop stalks, give these crustaceans a comical, alien appearance.

Ghost crabs were abundant on Longboat Key this past week; both immature and adult crabs scurried across the beach throughout the day, diving into their burrows or out into the water as walkers approached. They feed on a wide variety of plant and animal life, including seaweed, carrion, sand fleas, mole crabs, stranded fish and sea turtle hatchlings; their taste for the latter has led to their persecution in some turtle recovery areas.

Named for their pale coloration, nocturnal activity and rapid disappearance into burrows, ghost crabs are a food source for night herons, great blue herons, raccoons and gulls. They are also threatened by beach erosion and, ironically, often succumb to artificial beach restoration efforts. For now, their welfare seems assured on Longboat Key!

Monday, October 20, 2008

A Feast at Low Tide

Yesterday morning, a low tide had doubled the width of the beach on Longboat Key. Broad sandflats spread toward the calm Gulf, cut by braided channels of seawater and dappled with temporary pools. The latter, adorned by the tracks of marine snails, harbored schools of fry, starfish and a host of crustaceans.

A hundred or more brown pelicans rested on the calm waters of the Gulf; each would eventually rise into the air and then plunge toward another school of fish. Nearby, sandwich and royal terns circled above the surface in large, noisy flocks, diving in sequence to snare a fingerling. Cormorants and ospreys also moved in to share the bounty and, beyond the outermost sandbar, a pod of dolphins rejoiced in the morning feast, diving for fish or twisting into the air.

On the beach, laughing gulls, great blue herons, snowy egrets, willets and white ibis stalked the shallow pools while short-billed dowitchers, sanderlings, ruddy turnstones, black-bellied plovers and red knots hunted across the sandflats. It was a scene of plenty on a mild, sunny morning in South Florida.

Sunday, October 12, 2008

A Retreat to Summer

Just as the autumn colors are spreading and the first winter storm is pushing out of the Rockies, we'll be retreating to summer for the next week. Obliged to check on our Longboat condo, we will enter the world of perpetual balminess (at least relative to our dramatic seasons in Missouri).

We'll leave the world of deciduous forests, rock bluffs, cornfields and great rivers and enter the kingdom of mangroves, ocean surf, bays and sand. Walnuts and oaks will give way to pines and palms. Hawks will become ospreys and laughing gulls will stand in for the raucous jays. Brown pelicans will glide overhead, roseate spoonbills will glow from the shallows and the shorebirds that visited our wetlands over the past few months will be racing along the beach.

And, of course, the cool, autumn air will be supplanted by the heat and humidity of South Florida. It will be a week of summer in the midst of autumn; somehow I'll survive.

Saturday, October 11, 2008

Western Snow

The first major snowstorm of the season pushed into the Northern Rockies and Intermountain West, yesterday, dumping up to a foot of snow. While this may seem premature to many Americans, the snowfall is actually a bit late this year; snowstorms commonly occur in this region by mid September (occasionally by late August).

Considered a nuisance in many parts of the country, snow is absolutely vital to the American West; with the exception of the Northwest Coast, this region is arid or semiarid, receiving less than 15 inches of precipitation in the course of a year. Rain, which is generally limited to isolated, seasonal thunderstorms, is not sufficient to support the natural habitats and human communities that occupy the region. Rather, it is the snowpack of the higher mesas and mountains that feeds the streams, diversifies the ecology and allows man to inhabit this dry, sunny landscape.

Accumulating faster than it melts, the snowpack will build through the winter and early spring, generally peaking in late February or early March. In shaded cirques or on high, north-facing slopes, snow may persist through the summer and, over many years, develop into mountain glaciers. Today, as our climate warms, these glaciers are retreating and the annual snowpack has become even more important. Snow is always welcome in the West!

Friday, October 10, 2008

The Dow and the Hawk

Yesterday afternoon, I returned to my office, logged onto CNN and found that the Dow had dropped another 800 points. Preferring to ignore the details, I logged off, turned on some music, propped my feet on the desk and enjoyed the view from my window. A red-tailed hawk soared above the campus, drifting slowly to the north; I soon felt a lot better.

While politicians, financial gurus and a worried public grapple with the worldwide crisis, the natural world goes on as usual. Leaves change, elk bugle, waterfowl congregate along flyways and whales head for tropical birthing grounds. Reacting solely to biologic processes, plants and animals do not worry about tomorrow. We humans, hobbled by fear and uncertainty, can find relief from our stress by retreating, however briefly, to the peaceful world of nature.

The red-tail, unlike many bird species, is not programmed to migrate south as winter approaches; he has no knowledge of the Gulf Coast and is perfectly content (and equipped) to endure the cold, gray weather of a Midwestern winter. A few months from now, I may see him again, huddled on a limb along I-70, oblivious to the wind and snow as he scouts for mice in the dead grass below. Perhaps the Dow will have recovered by then; either way, it won't bother him!

Thursday, October 9, 2008

The Ferocious Loner

Ferocious yet reclusive, wolverines inhabit the vast northern forests of Russia, Europe and North America; the North American subspecies, which once occupied northern New England and the Great Lakes region, extends southward through the Cascades and Northern Rockies (some have been sighted as far south as California and Colorado). Since they are primarily nocturnal and favor remote areas, these hardy mammals are rarely observed.

Equipped with thick fur, broad paws and powerful jaws, wolverines are loners, canvassing their extensive territory for food; though they often consume berries, wolverines are primarily carnivorous, hunting small mammals and feeding on the remnants of larger animals killed by wolves, bears or mountain lions. Despite their relatively small size (adult males weigh up to 40 lbs.), wolverines will attack young deer, caribou or moose and have been known to kill adults stranded in heavy snow.

This largest member of the weasel family has also been called the devil bear or skunk bear; the former title reflects their ferocity while the latter is derived from their potent scent glands. Maintaining a territory of 200 square miles or more, the males mate with several females in the course of a summer; implantation is delayed and the females give birth to 2-3 kits by early spring. The young stay with their mother for two years and then move off to establish their own vast territories.

Wednesday, October 8, 2008

The Contrarian Bird

As the first hints of winter blow across North America, many birds begin their migration to southern climes. Those dependent on insects or nectar are the first to leave, staying ahead of the freeze line as it gradually dips across the Continent. More hardy species, capable of surviving on seeds, berries and hibernating insects, do not migrate or merely move from the North Woods to the Temperate Zone. Some, such as great gray owls, snowy owls and snow buntings are irruptive species, moving south only if forced to do so by heavy snows or dwindling food supplies.

Like the flatlanders, mountain birds escape the stress of winter by heading to milder climes; in many cases, this is limited to vertical migration, a descent to elevations with warmer temperatures and less snow. Along the Colorado Front Range, a variety of mountain birds visit the urban corridor during the winter months; these include mountain chickadees, red crossbills, Cassin's finches, Townsend's solitaires and gray-headed juncos, among others.

But there is one bird that defies this pattern, moving to higher elevations for the winter. The blue grouse, common throughout the western mountains, from northwest Canada to New Mexico, summers and breeds in the open, ponderosa pine woodlands of the lower mountains and foothills; there they feed on insects, seeds, berries, buds and pine needles. Come winter, they ascend to the Subalpine Zone, surviving on the foliage of conifers (pine, spruce and fir). There must be a good reason for this behavior......but it escapes me!

Tuesday, October 7, 2008

Heaven on Earth

Many religious zealots live to die. Their entire earthly existence is devoted to achieving eternal life and death is the portal to that reward. Focused on this goal, they overlook the many joys that our earth-bound life can bring. Curiosity about the natural world is often a victim of that zealotry.

One need not be a hedonist to appreciate the many wonders of this planet. Expensive journeys and high-tech equipment are unneces-sary. Relatively few people fully explore their own yards and neighborhoods, let alone the nearby marsh or woodlot. Just coming to grips with the night sky can keep us enthralled for decades and weather buffs have an endless source of entertainment.

Unfortunately, many find it hard to balance natural science and spirituality. It's often easier to take a simplistic view of life, devoid of uncertainties. If more of us accepted this Earth as our paradise, we'd be more committed to protecting and enjoying what we have. In the end, we'd all be better off.

Monday, October 6, 2008

Insect Deadline

The insects of the Midwest are approaching their deadline. With the first freeze only a week or two away, they are busily ensuring the survival of their genes. Most species do not overwinter as adults and must mate and deposit eggs before they, themselves, succumb to the cold.

Our current, balmy interlude is providing a perfect opportunity and the chorus of cicadas, crickets and katydids made last evening sound like August. Warm, sunny days have the bees combing the flower beds and the dragonflies making their last forays of the season. Harvestmen roam the woodpiles, butterflies still brighten the shrubbery and flying insects attract squadrons of chimney swifts, soon to depart for southern climes.

While honey bees overwinter in hives, pregnant bumblebees retreat to underground dens and some species survive beneath leaf litter or in man-made structures, most adult insects will die with the first hard freeze. Their species will live on in the eggs or cocoons attached to vegetation or as larvae in the ponds or soil. Come spring, those not eaten by birds, moles, mice and shrews will give rise to the next generation.

Sunday, October 5, 2008

Unicorn of the Sea

Narwhals are toothed, Arctic cetaceans, best known for the prominent tusk of the adult male. The latter is actually an outward eruption of the upper, left incisor, which develops into an elongated, twisted tusk; up to 10 feet long, it is used for mating jousts but may also serve other purposes (chemical sensing, communication etc.). A small minority of males have a pair of these structures and some females grow a short, narrow tusk.

Their name (Norse for "corpse whale") reflects their blotchy skin pattern, tubular shape and habit of lounging "belly up" on the surface of the ocean. After mating in spring, these highly vocal whales congregate in shallow, coastal bays for the summer months; there, females give birth to calves conceived the previous spring (gestation averages 15 months). The calf nurses for 4-5 months and will stay with its mother for almost two years.

As summer gives way to autumn, the narwhals break into small pods, spending the colder months among the ice flows of the Arctic Sea. Protected by a thick layer of blubber, they will feed on cod, halibut, shrimp, squid and young seals; adult males grow to a length of 16 feet and weigh up to 1.8 tons (females are about 2/3 their size). Narwhal predators include polar bears, killer whales and some Native American tribes; despite a lifespan of 50 years, this species may be among the early victims of global warming.

Saturday, October 4, 2008

October Marsh

The early October marsh is not your noisy, buggy wetland of late spring and summer. Gone are the colorful songbirds, flitting among the thickets. Absent is the croaking of frogs and the trilling of toads. Gone are the clouds of mosquitoes that draw squadrons of swifts and swallows to these prolific shallows.

This is a quieter place with subdued colors and patient hunters. Crickets and grasshoppers move among the dried vegetation, potential victims of leopard frogs and garter snakes that lounge in the shoreline grass. The frogs, now silent residents of the wetland, remain wary of predators (snakes, herons, mink) and spring into the shallows as you approach. Painted turtles, soon to winter in the bottom muck, crowd onto logs and bask in the warm sunshine of early autumn.

Out on the lakes and larger ponds, ducks and grebes are arriving from the north; their numbers will increase through the month as more intense cold fronts push across their breeding grounds. As the days continue to wane, winter songbirds grace the marshland thickets, content to feast on the seeds of summer's past glory.