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Showing posts from August, 2009

Brush Pile Wilderness

Eyesores to those with manicured yards, brush piles offer a miniature ecosystem for those of us interested in nature study. These mounds of decaying vegetation harbor a diverse population of insects, spiders, worms, caterpillars and other invertebrates, a wealth of plant fruits and seeds and a variable mix of fungi. In turn, these life forms attract wrens, sparrows, thrashers, towhees, mourning doves, field mice, shrews, toads and snakes which, themselves, are potential prey for fox, coyotes, hawks and owls.

Beyond their role in residential food chains, brush piles offer nesting sites for a variety of birds and small mammals and provide shelter for many creatures during the harsh winter months. Indeed, the naturalist will find a changing population of wildlife throughout the seasons as summer residents (house wrens, insects, toads, snakes) give way to winter sparrows, juncos and small mammals during the colder months; winter is also a good time to look for insect pupae, potential sn…

First Autumn Chill

Today brought the first autumn chill to central Missouri. Though the afternoon high was near 70 degrees F, a steady north breeze and intermittent cloud cover produced the first cool day of the season. We may still be in August but it felt more like early October.

A jacket provided comfort on our morning visit to the local nature preserve where the chill seemed to energize the late summer residents. Cardinals, indigo buntings and American goldfinches flashed through the woodland while killdeer noisily patrolled the expanding mudflats. Bullfrogs and green frogs, finding refuge in the warmer water, peered from the shallows, wary of herons and water snakes that haunt the seasonal lake. Gold and purple wildflowers (goldenrod, black-eyed susans, blazing star, thistle) adorned the meadows, glowing beneath a brilliant sun and a deep blue sky.

Back home, the walnut trees, heavy with fruit, are beginning to shed their yellowing leaves while the dark berries of the pokeweed, ripening on brigh…

Earth's Longest River

While the Amazon is Earth's largest river (by volume), the Nile, of central and northeast Africa, is the longest. Rising near an elevation of 8800 feet in the mountains of southern Rwanda, the White Nile flows northward, passes through Lake Victoria and joins the Blue Nile near Khartoum, the capital of Sudan; these combined tributaries continue north to the Mediterranean Sea, producing a vast delta at Cairo and yielding an official length of 4184 miles (2700 of which are provided by the White Nile). In contrast, the Blue Nile, which originates at Lake Tana, Ethiopia, is only 870 miles long but contributes more than 80% of the Nile's flow during the wet season of May to August.

The junction of the White and Blue Niles occurs at an elevation of 1200 feet and the River's last major tributary, the Atbara, enters just 200 miles north of this point. Beyond this tributary, the Nile makes a broad curve to the south (the Great Bend) before flowing across the vast deserts of northern…

Diluted Soup but Little Punch

After a brief taste of fall, hot, humid air pushed into mid Missouri yesterday afternoon as a cold front loomed to our northwest. With temperatures pushing 90F and dew points near 70F, we were back in the summer soup.

Today, the cold front is nudging toward the southeast and its central low pressure sits over our region. Not energized by the jet stream, the front has little punch and, though some storms are expected, no severe weather is likely to occur. The band of heat and humidity is now off to our east, curving up the Mississippi and Ohio Valleys, while cooler and drier air is filtering in from the northwest, diluting the soup that blanketed our State yesterday; this afternoon, both the high temperature and the dew point are ten degrees cooler.

Since this cold front is not as potent as the one that deflected Hurricane Bill to the north, Tropical Storm Danny may have more impact along the Eastern Seaboard than did its more powerful predecessor. Heavy rains and strong winds may la…

The Dreaded Horsefly

Having spent most of my childhood outdoors, I've always been comfortable around wild creatures. Snakes, mice, bats, owls, bees and spiders evoke more curiosity than fear. But horseflies, those large, aggressive residents of open woods and wetlands, induce a flight reaction in my brain; likely imprinted by several painful bites during my youth, this visceral impulse is always triggered when one begins to buzz my head.

Represented by more than 200 species in North America, horseflies lay their eggs on moist vegetation. The larval worms feed throughout the remainder of the summer and early fall, wintering in ponds or within the soil. Emerging in spring, they pupate for a few weeks and then re-emerge in the adult form, ready to harass humans, horses, deer and cattle. Actually, as in mosquitoes, it is only the female that feeds on mammalian blood, a painful event for her victims; the male, though just as annoying in other ways, feeds on nectar, carrion and small insects.

While all life f…

The Supplement Craze

Every year, Americans spend billions of dollars on nutritional supplements, including vitamins, minerals and herbal agents. The great majority of those taking these products receive no proven benefit and many experience side effects, either directly from the supplement or secondary to its interaction with prescription medications.

While a multivitamin is generally beneficial to the very young and elderly and while nutritional supplementation is vital in certain medical conditions (GI pathologies causing malabsorption, osteoporosis and others), a well balanced diet will supply all of the metabolic needs for the vast majority of individuals. Combined with regular aerobic exercise, a diet rich in fresh vegetables, fruits, dairy products and natural protein is the ideal way to remain healthy; expensive and potentially harmful supplements offer no additional benefit.

Nevertheless, television, print media and the internet are loaded with commercials for these agents, touting special benefit…

The Flocks of Autumn

In spring and early summer, most birds pair off to nest. While some species roost and nest in colonies, the birds usually move about alone, in pairs or in small family groups. By mid-late summer, shorebirds begin to migrate south in small flocks while other species (blackbirds, gulls, mourning doves, swallows) start to congregate.

Flocks of nighthawks circle southward in the evening skies of late August, moving ahead of the coming chill. September brings the first wave of migrant songbirds and early ducks (blue-winged and cinnamon teal) appear on our wetlands. By October, flocks of waterfowl (ducks, grebes, white pelicans, cormorants) are building, joined by swans and geese in November.

Generally wintering in sizable flocks, these avian travellers will return in the spring, to begin their season of relative solitude. For now, we can look forward to their autumn exodus, a spectacle that has long stirred wanderlust in the soul of man.

Blaming God

When Katrina slammed into New Orleans, Pat Robertson and fellow evangelists suggested that God was punishing that sinful metropolis; no doubt, they expressed similar views following earthquakes in China, Iran and that enclave of liberalism, California. And now, the Governor of Florida has proclaimed that his State's recent good fortune (i.e. no destructive hurricanes) can be attributed to the power of prayer.

The views expressed by these religious zealots evoke the image of a vengeful and vindictive God who, if offended and not appeased by ritual, unleashes natural disaster on human populations. Directed at an audience of uneducated and gullible Americans, their words are designed to appease the faithful while attracting new viewers and voters.

Though many Americans may accept these proclamations as nothing more than humorous sideshows in the great drama of modern culture, some of us are concerned that they represent a dangerous undercurrent in human society. Centuries after the …

A Benevolent Front

Having pushed through Columbia during the early morning hours of August 20, bringing strong winds, intense lightening and heavy rain, the latest cold front has pushed on to the south and east. In its wake, cooler, drier air has spread across the Midwest and will continue to expand for the next few days, providing an early taste of autumn and a welcome reprieve from the heat and humidity of recent weeks.

While bringing glorious weather to the Midwest, this potent front is also responsible for steering Hurricane Bill to the north, keeping its dangerous winds off the East Coast. As the trough continues to broaden and push eastward, the path of the storm will actually curve back to the northeast, posing problems for the Canadian Maritimes but sparing the U.S.

Weather events are governed primarily by shifts in the jet stream and timing is crucial when it comes to the trajectory of hurricanes. Had the front stalled in the Midwest, Bill might have slammed into Florida or the Carolinas, caus…

Fate and Destiny

Humans have long been enamored with the concepts of fate and destiny. While both imply that the course of our life is predetermined, fate has negative connotations (e.g. early death) while destiny hints of fame and success. Like many other products of the human mind, both are delusions and accepting them can have significant consequences.

Beyond the effects of happenstance (good or bad luck in the secular sense, the hand of God to believers) the course of our life remains under our control. Those who focus on fate or destiny are prone to make cavalier or irresponsible choices, either assuming that behavior has no relation to outcome (fate) or that the purpose of their life (destiny) will protect them from negative consequences. Such points of view, relatively common in teens and young adults, often saps motivation and promotes risky behavior.

Acknowledging that we have the means to reach our goals is the first step toward achieving them. By refusing to accept the notions of fate and …

Greed, Fairness & Health Care

Most primary care physicians, those front-line, modestly compensated soldiers of American health care, likely favor a national insurance program. After all, they regularly witness the devastation of acute, catastrophic illness, the stress of a sudden, unexpected loss of income and the manipulative practices of health insurance companies.

Financed by the pharmaceutical and insurance industries and coordinated by conservative politicians, the recent backlash against health care reform has gripped the nation, triggering contentious arguments and baseless fears. Those that foment this turmoil are protecting their profit margins while a gullible public, many at personal risk for medical catastrophe, blindly join the protest. In reality, the wealthy, flush with insurance coverage and unaffected by co-payments or merely reluctant to share their good fortune (whether earned or inherited); they will continue to visit convenient, high priced urgent care centers for symptoms of the common cold. A…

Ana and Bill

The development of a tropical storm requires several ingredients: a disturbance in the atmosphere (often a tropical wave), warm ocean water, a plentiful supply of heat and humidity at lower levels and relatively weak upper level winds. Strong winds in the upper atmosphere sheer away the building storm tops, disrupting the vertical development that is essential to the heat engine of a tropical cyclone.

While both tropical storms Ana and Bill developed in a similar fashion (organizing through the sequence of tropical wave and tropical depression), Ana's life as a tropical storm was short, a consequence of her encounter with upper level sheer. Now a disorganized tropical depression in the Caribbean, she may redevelop in the southern Gulf of Mexico as upper winds abate; should that happen, she could be reborn as a hurricane.

Meanwhile, Bill, following in Ana's wake, has strengthened into a hurricane and is projected to intensify over the coming days. Fortunately, an approaching c…

Summer Fog

Dense fog shrouds Columbia this morning, the combined effect of yesterday's heavy rain and the presence of a cold front across central Missouri. Fog is the result of air that has reached its dew point; in other words, the air is fully saturated with water vapor. Further cooling would lead to precipitation while solar radiation (which will intensify by later in the morning) heats the air above its dew point and dissipates the fog.

In summer and fall, fog generally develops when cool air settles over warm, moist ground; conversely, in winter or spring, it typically occurs when warm, moist air spreads above cold ground. In either case, calm conditions favor fog development while the presence of wind tends to mix the air, disrupting its saturation. Since cool air, having a greater density than warm air, settles in topographic depressions, summer and autumn fog is most common in river valleys.

Fog is especially common in coastal areas, where large bodies of water moderate the air tempera…

Florida's Anoles

Anyone who visits Florida is almost certain to encounter a large number of small lizards, scurrying among the shrubbery or racing across the trails and walkways. The green anole (also called the Carolina anole) is native to the State and has long been sold in American pet stores, where, due to its color-changing abilities, it has been incorrectly labeled a chameleon.

Over the past century, the brown anole, a native of Cuba and other Caribbean islands, has been introduced to Florida and has rapidly spread across the State (and throughout other regions of the Southeast and Gulf Coast). Similar in size, diet and habits to the green anole, this exotic species appears to be more comfortable in disturbed areas and, in light of ongoing "development" across Florida, now appears to be more common than the native, green anole. Both feed on insects and other small invertebrates and are known to consume eggs or hatchlings of their own or other anole species. Adult males aggressively def…

August on Longboat Key

Our week on Longboat Key, Florida, was, as expected, characterized by hot, humid weather and frequent thunderstorms; on our last day, a tropical depression formed in the Gulf of Mexico, soon to become Tropical Storm Claudette as it approached Panama City. All of the clouds and hazy air, combined with my intolerance for late night viewing, had a negative impact on my plans to observe the Perseid meteor shower.

Since this was my first August trip to the Key, certain seasonal changes were evident. While all of the usual coastal birds were represented, their numbers (with the notable exception of ospreys) were lower than during the cooler seasons; especially evident in the case of brown pelicans, I suspect that this reflects a dispersal to more northern climes in summer and that I am used to observing the concentrating effect of a North American winter. One treat was the opportunity to see many of the shorebirds (sanderlings, short-billed dowitchers, black-bellied plovers), just down f…

Perseids over Florida

Not fond of crowded beaches, congested amusement parks or trail parades, my wife and I have taken few summer vacations. We prefer off-season trips, when rates are lower and, more importantly, when some degree of solitude is possible.

Nevertheless, we're off to Florida this week, partly to check on our condo and primarily to visit our son and attend a ceremony at his medical school. We are, of course, looking forward to the latter and will no doubt enjoy the beach walks, despite the hot, summer weather. A tropical storm would be interesting but, in this El Nino year, the Atlantic basin has been rather quiet.

I do hope to catch the Perseid meteor shower, which peaks from August 11-13 each year. Remnants of the Swift-Tuttle comet (which orbits the sun every 130 years) the Perseid meteors are generally abundant; more than 100 per hour can be seen if a bright moon or city lights do not obscure the view. Since Longboat Key is primarily residential and a good distance from the urban glow …

The Dome of August

After a rather cool and pleasant July, we are back in the heat of a Midwestern summer. As is typical in August, a broad dome of high pressure has developed over the Southern Plains and South-Central States. Within this ridge, sinking air, clear skies and light winds can produce stifling heat, often combined with high humidity.

Expanding and contracting over the next month, the dome will deflect Pacific Fronts to the north, keeping the Northern Plains and Upper Midwest in a stormy pattern while augmenting the prolonged Texas drought. This late summer ridge is also partly responsible for the annual, Southwest monsoon; combined with heat-induced low pressure over the deserts of southeastern California and southern Arizona, a fetch of moisture (from both the Gulf of California and the Gulf of Mexico) is pumped across Mexico and into the Four Corners region. Riding the outer edge of the dome, this moisture-laden air flows northward across the mountains of New Mexico and Colorado, feedin…

Stress and Time

Our modern human lives can be stressful, with responsibilities tugging from various directions. In turn, this chronic stress can lead to health problems, including anxiety, headaches, ulcers and cardiovascular disease.

In my experience, stress results more from the anticipation and perception of our responsibilities than from the duties themselves. We are often overwhelmed by the multiple tasks that face us and sense that we don't have the time to accomplish them. Taking time to relax (an important choice) may heighten the anxiety, adding a layer of guilt to our troubled minds.

In reality, we usually have plenty of time to handle our responsi-bilities but tend to waste a good deal of it on mindless activities such as television, computer games and recurring conversations. I suggest making a list of "extra duties" that demand your attention in the coming week and commit to accomplish one (and only one) each day. By breaking down this gauntlet of looming responsibilities int…

The Jurassic Period

The Jurassic Period, 190-135 million years ago, was the middle segment of the Mesozoic Era, the Age of Dinosaurs. While small, herbivorous dinosaurs had appeared in the Triassic, the Jurassic witnessed the rise of their larger cousins, such as allosaurus, stegosaurus and brontosaurus. Earth's continents, now split west to east by the Tethys Sea, still occupied the warmer latitudes, fostering dense vegetation that sustained these giants. Small mammals already scurried beneath the copious plant life but would be dominated by dinosaurs throughout the Mesozoic.

Flowering plants appeared during the Jurassic, some 200 million years after ferns and early conifers graced the scene. Other newcomers included pterosaurs and archaeopteryx; while the former were superb gliders, the latter was perhaps the most primitive relative of modern birds. The Atlantic began to open in the middle of the Period and the Sundance Sea covered most of what is now the High Plains and Rocky Mountain region of Nor…

The Yukon River

Rising in alpine lakes of northernmost British Columbia, the Yukon River flows northwestward through the Yukon Territory of Canada and into eastern Alaska. There it curves to the southwest and winds across the flatlands between the Brooks and Alaska Ranges, completing its 2300 mile journey to the sea.

Along the way, this great river is fueled by melting snow and ice, alternately clear or turbid, depending upon the quantity of glacial debris; much of the latter is contributed by the White River, dropping northeastward off the Wrangell-St. Elias Mountains. Descending from the pristine lakes of British Columbia, the headwater streams merge south of Whitehorse and are joined by the Pelly River (draining the west slope of the MacKenzie Mountains) north of the city. At Dawson, the Klondike River, famous as the site of the 1896 Gold Rush, joins the Yukon before it enters Alaska; at the border, the river is barely 1000 feet above sea level and will cross the entire State at a very low rate …

Hints of Autumn

While there is still plenty of hot, muggy weather ahead, the first signs of autumn are evident across Missouri. Of course, the days are noticeably shorter and, as a result, the mornings bring a welcome chill. Our lawns, growing at a slower pace, are now littered with the first crop of walnuts and, except for the cardinals and Carolina wrens, most birds have settled into their late summer conversation of subdued trills and chirps.

Out in the country, blackbirds and mourning doves are gathering in larger flocks and mixed groups of swallows and bluebirds gather on power lines. The purple and yellow wildflowers of late summer now adorn the fields while swaths of Queen Anne's lace border our country roads. Wetlands, devoid of heavy rain for the past few weeks, are beginning to dry out, their amphibian and reptilian residents now more visible from lakeside trails; in concert, the growing mudflats host an increasing number and variety of migrant shorebirds.

Within a few weeks, nighthawks …

South Dakota Memories

Raising our children in Metro Denver, we took many road trips to scenic destinations throughout the West. Most of these treks were over spring break or during long autumn weekends, designed to avoid summer crowds. While Yellowstone, the Canyonlands and Carlsbad Caverns were among the most spectacular, a trip to South Dakota was one of the more memorable excursions.

Over the course of two days, we experienced the natural and historic wonders of the Black Hills, Custer State Park, Wind Cave National Park, the Badlands, Mt. Rushmore, Jewel Cave National Monument and the Crazy Horse Memorial, then in progress. En route, we also crossed parts of Wyoming and Nebraska that were new us but, unfortunately, did not have time to visit Devil's Tower. Accompanied by deep blue western skies and pleasant, autumn weather, it remains one of our more talked about road trips.

One particular event during that weekend left a significant impression on me and, I assume, on other members of our family. Whi…

America's Drug Culture

Mention "drug culture" and most Americans think of smugglers, violent cartels, street corner pushers and back alley crack houses. But there is a legal drug dependence that grips much of Western society and its tentacles continue to spread.

While modern medications have provided a significant benefit to human society and have played a major role in extending our life span, many Americans count on these potent agents to rescue them from a lifestyle of poor choices and risky behavior. Fueled by the pharmaceutical industry, this attitude is spreading in concert with the culture of obesity, itself the stepchild of inactivity and poor dietary habits. Of course, obesity leads to many other heath problems, including diabetes, hypertension, heart disease, sleep apnea, degenerative arthritis and a number of cancers. The use of drugs to treat these conditions leads to a host of side effects, many of which are managed with other medications. By middle age, many Americans are on a laundry…