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Showing posts from June, 2008

Canadian Rescue

Cool, dry air pushed into Missouri over the past 48 hours, courtesy of a Canadian cold front. Displacing the hot, muggy air that enveloped us for most of the week, it was a refreshing and invigorating change. Yard work was a pleasure and the desire for exercise returned. One could almost imagine that the leaves were beginning to turn or that the rumble in the distance came from the University's marching band. Even the scent of neighborhood cookouts suggested pregame tailgates.

Then I remembered: we still have to get through July and August! An escape to Colorado and a planned trip to Newfoundland should ease the burden. Life can be tough.

Evening on the Floodplain

Cool, dry air, clear skies and a flooded landscape characterized the Missouri River Valley last evening. A raft of flotsam had collected behind the Perche Creek bridge, attracting a pair of red-headed woodpeckers that hopped among the logs, picking off insects. A flock of cliff swallows, temporarily evicted from their homes beneath the bridge, gathered on nearby power lines.

Out in the Eagle Bluffs Conservation Area, shallow pools covered most of the fields and the permanent waterways lapped against the levees. Waterfowl had dispersed across the flooded valley and were represented by only a few Canada geese and a mother wood duck with her maturing brood. Great blue herons, like posted sentries, guarded the shallows and turkey vultures soared low above the fields, searching for stranded fish. Indigo buntings sang from roadside saplings while lark sparrows and horned larks scoured the gravel for windblown seeds.

A lone red-tailed hawk circled above the refuge, perhaps over-whelmed by the …

The Nature of God

Once hominids were intelligent enough to wonder, the concept of God was born. By then, the Universe was already 13.6 billion years old.

Since that time, God has been the target of man's hope and the refuge from his fear. Early human civilizations worshipped numerous gods, each associated with specific needs and threats. Rituals, designed to appease these divine powers, became an integral part of their culture. Modern, Western religions, though monotheistic and based on a humanized God, were established before the scientific revolution and retain a focus on ritual.

Science cannot prove nor disprove the existence of God but it does lend perspective to man's interpretation of the natural world. We now know that the Earth is not flat; it does not lie at the center of the Universe, nor at the center of our galaxy, nor even at the center of our solar system. We have come to understand the natural forces that shape our planet and the evolutionary processes that produced our spec…

Colorado's Jays

Five species of jay inhabit Colorado. All are noisy, aggressive and omnivorous birds but each is associated with a unique life zone; as is usual in nature, the borders of their range tend to overlap.

Blue jays, common throughout eastern and central North America, spread into Colorado via the South Platte and Arkansas Valleys and are now common along the Front Range urban corridor; they are easily found along wooded streams and in residential areas. Scrub jays inhabit foothill shrublands and lower canyons throughout the State, generally at elevations between six and seven thousand feet. In the higher foothills and mountains, Steller's jays are found, favoring the ponderosa parklands and Douglas fir forests that dominate the vegetation of the Montane Zone (roughly 7-9000 feet); they may be seen as high as timberline in summer and occasionally descend to the Plains in winter.

Gray jays, also known as Canadian jays, prefer the high forests of the Subalpine and Hudsonian Zones, betwee…

Steam Bath

Less than a week past the summer solstice, I'm ready for September. Hot, humid weather has settled into Missouri, with highs near 90 and dew points in the seventies. Though I appreciate seasonal change, such conditions sap my energy and I long for the next wave of cool, Canadian air.

Of course, there's still plenty to see and explore on these muggy, summer days. The mimosas and elderberries are in bloom, insects are peaking in number and variety and frequent thunderstorms keep the weather interesting (though their rains boost the humidity). While I admire the swifts and swallows that thrive in this Midwestern steam bath, I'll limit my outdoor jaunts to the early morning and evening hours. Man may have evolved in such a climate but I feel out of place.

A cold front is due by the weekend and the humidity should drop significantly. Until then, I'll get some reading done and appreciate my indoor job.

Pine Mountain

In southeastern Kentucky, two high ridges, separated by the Cumberland River Valley, parallel the Virginia border. These prominent spines are part of the Cumberland Mountains, the southeast edge of the Appalachian Plateau and the westward extension of the Allegheny Front. The more southern ridge is Cumberland Mountain which harbors the famous Cumberland Gap, just outside of Middlesboro, Kentucky.

The northern ridge, extending from Whitesburg, Kentucky southwestward into Tennessee, is known as Pine Mountain; after flowing along the south side of this ridge, the Cumberland River cuts through to its north side at Pineville and continues westward to Cumberland Falls and Lake Cumberland. Pine Mountain State Resort Park, just west of Pineville, is an excellent place to explore the ridge; it is the oldest Park in what is arguably the finest State Park system in the country. Numerous trails lead across the south face and atop the high spine of Pine Mountain, passing waterfalls, a natural brid…

Clifton Gorge

Slicing through the farmlands of southwestern Ohio, Clifton Gorge is a scenic wonderland for naturalists. Though its rugged walls of Silurian dolomite were deposited 400 million years ago, the gorge itself was carved by a torrent of glacial meltwater near the end of the Pleistocene, some 12,000 years ago. Documenting this history, the shaded walls of the chasm harbor relict, periglacial vegetation, including hemlock, Canadian yew, arborvitae and mountain maple.

Stands of chinquapin oak cover south-facing hillsides and over 340 species of wildflower have been found in the gorge. Numerous springs and seeps produce ideal conditions for the sixteen species of fern that grace the rocky walls and provide ideal habitat for salamanders (8 species live here). Red squirrels are common in the hemlock areas and, as one might expect, a large variety of songbirds are drawn to this chasm, which offers protection in winter and a cool retreat in summer.

Hikers will find an excellent trail network at…

A Feast of Froglets

On our visit to the Forum Nature Area, yesterday, my wife and I found a zillion froglets along the marshy shores of the flooded, seasonal lake. While most appeared to be young leopard frogs, they were difficult to observe, springing from the wet vegetation like hordes of grasshoppers. Within the shallows, other frogs were in various states of metamorphosis, from tadpoles with legs to froglets with tails. Once they transform from a reliance on gills to the use of lungs, the froglets emerge from the water to feed on insects, diving back when danger is sensed.

These swarms of froglets highlight the abundance of life in our rich, unspoiled wetlands and provide natural entertainment for adults and children alike. More importantly, they offer a feast for the herons, snakes, snapping turtles, mink and raccoons that prey on these amphibians. Those that survive will grow rapidly through the summer, doing their part to control the wide variety of insects that inhabit and breed in the wetlan…

The Cost of Oil

The price of oil has surged in recent months, producing hardships for individuals and businesses alike. The cause for this phenomenon appears to be mulifactorial: increasing worldwide demand (especially in developing nations), political unrest in oil producing countries, limited refinery capacity, speculation and a diminished U.S. dollar are all playing a role. But, despite the pain levied on consumers, we are, in many ways, beginning to appreciate the true cost of using oil as fuel.

Though I have some personal doubts regarding the degree to which human industry is responsible for global warming, there is little doubt that we are have produced 100% of the environmental pollution; the procurement, transport and burning of fossil fuels have contributed significantly to the pollution and destruction of natural habitat. Recognizing that high oil prices and consumer stress are providing an opportunity, U.S. oil companies are renewing their efforts to drill in ANWR and other environmenta…

Turtle Tots

It seems to be a good year for aquatic turtles in mid Missouri. Our visits to the Forum Nature Center, in Columbia, have turned up a large number of small painted turtles and red-eared sliders this season; local flooding may have drawn some of these reptiles from more permanent lakes and ponds in the area.

After wintering in the muddy bottoms of lakes and ponds, aquatic turtles emerge by April and mate in mid spring. Pregnant females leave the water in June to lay six to thirty eggs in a depression that they dig near the shoreline (larger, older females generally lay the most eggs). If not eaten by raccoons or other scavengers, the young turtles hatch in mid-late August and head for the water. Over the first few years, they are primarily carnivorous, feasting on insects, other invertebrates and small fish; as they mature, they become omnivorous, adding carrion and aquatic plants to their diet. Those that do not fall prey to herons, mink, otters, snakes, large fish or snapping turtles w…

Altitude Sickness

Many Americans will head to the National Parks and mountain resorts of the West this summer and, unfortunately, some of their vacations will be marred by altitude sickness. This common malady is triggered by an impaired ventilatory response to hypoxemia, an increased blood flow to the brain, increased blood pressure in the lungs and an altered acid-base state, especially in the brain and spinal fluid. The risk for developing all forms of altitude sickness is increased by a past history of altitude-related illness, a rapid ascent (>1000 feet/day), a home elevation under 3000 feet, age under 50 years and by strenuous activity prior to acclimation; the altitude at which one sleeps (while in the high country) also correlates with the risk level.

Acute mountain sickness, the most common and least serious form of altitude-related illness, is generally characterized by a mild headache, nausea, fatigue, dizziness and insomnia; in addition to the risk factors listed above, obesity predispo…

Floodplain Roulette

During most of our history, humans have been a nomadic species, living in temporary camps as we followed game and explored our planet. Early man surely noticed that many rivers lie on broad, flat plains but he had little reason to wonder about the evolution of that landscape. Though he often camped along rivers for water, food and transport, he was free to move on when floods developed.

Modern man has come to understand the natural history of rivers; he knows that glaciation, climate fluctuation and periodic flooding have all played a role in the formation of their floodplains. Yet, drawn by the many benefits that rivers provide, including the rich soil of their valleys, he has chosen to build permanent settlements on these ancient channels, relying on dams and levees for protection. Unfortunately, his brief life span (and the relatively short history of record keeping) cause him to underestimate the extent and power of massive, periodic floods.

Once again, we are witnessing destruc…

The Yellowstone Time Bomb

Yellowstone National Park, renowned for its scenic vistas, abundant wildlife and geothermal wonders, is a relatively recent addition to the American landscape. Formed by a massive volcanic explosion 2 million years ago (at the onset of the Pleistocene Ice Age) and by subsequent eruptions 1.2 million and 600,000 years ago, the Park's magnificent topography stretches across the broad, remnant caldera of those volcanic blasts. When will the next eruption occur? A look at the spacing of previous eruptions is certainly unsettling.

Yellowstone's geysers and hot springs attest to the continued presence of a "hot spot," a mantle plume close enough to the surface to generate these hydrothermal features. And recent Park surveys have confirmed a gradual bulging of the region's crust. Whether the risk of a major eruption has been reduced by previous volcanism and by subsequent movement of the North American Plate remains uncertain.

Like the San Andreas Fault and the Cascade Vo…

Islands of Water

Mention islands and most of us think of land masses that protrude above lakes and oceans. But, in desert regions, isolated mountain ranges produce the opposite effect, yielding pockets of moisture in a sea of dryness. Reaching high into the atmosphere, these "sky islands" are bathed by cool air and receive "upslope precipitation" from all directions. As a result, the mountain slopes are cloaked by bands of vegetation, corresponding to the change in climate that occurs with increasing elevation.

Such islands of water are common throughout the western U.S., especially in the vast, dry terrain between the Sierra Nevada and Rocky Mountain chains. Requiring an annual precipitation of 15 inches or more, a zone of juniper and pinyon pine begins above elevations of 5500 feet. Nearing 7000 feet, one encounters open woodlands of ponderosa pine and, on shaded slopes, forests of Douglas fir. Aspen and lodgepole pine begin to appear above 8000 feet, mixing with Englemann spruce,…

A Prime Time Death

The recent, unexpected death of Tim Russert, a renowned and beloved TV journalist, brought deep sorrow to his family, friends, colleagues and viewers. The death of a relatively young, vibrant person is always disturbing and, the better we know him, the more it triggers our own sense of mortality.

Religious people, of which Mr. Russert was one, often accept these tragedies as part of God's plan; in their view, God delivers both happiness and pain. Pure fatalists, on the other hand, harbor the conviction that "when your time is up, there's nothing you can do about it."

Those of us in the medical profession witness many early deaths in the course of our career. While many are due to trauma or to unpreventable illness, a significant percent result from poor lifestyle choices or from underlying, treatable conditions. A fatalistic view of life overlooks or denies the control that we have over our health and, thus, over our longevity. Tobacco use, excessive alcohol consu…

Insect Days

Insects play an important role in the natural world throughout the year. During winter, when most species are in suspended animation as eggs or pupae, these primary consumers provide important nourishment for birds and small mammals. Come spring, as the soil thaws, new vegetation appears and the ponds open, they begin to emerge; the tide of their recovery peaks by early summer and continues until the frosty nights of autumn.

Today's hot, humid weather has the annual cicadas buzzing for the first time this season. Down at the local wetland, hordes of dragonflies were hunting across the still waters, where whirligig beetles made frenzied patterns on the surface. Mosquitoes will rise from the marsh this evening and fireflies will flash from residential trees and shrubs, delighting adults and children alike. Then, of course, there are the numerous beetles, butterfies, moths, flies, crickets, grasshoppers and other insects that inhabit our woodlands and fields.

Checking the explosive pop…

Nighthawk at Noon

Common nighthawks are summer residents throughout most of North America and we tend to associate them with calm, summer evenings when they hawk for insects above our cities and towns. Easily identified by their halting flight, loud "peents" and prominent white wing patches, they are best observed at dusk; they are also common at sports stadiums where the bright lights concentrate their prey.

But, unlike other nightjars (such as whip-poor-wills and chuck-will's-widows), the common nighthawk is often active during the day, especially after heavy rains send clouds of insects into the air. And though they are generally associated with open woodlands and urban areas, they inhabit a wide variety of landscape. Today, travelling along I-70 in western Kansas, I watched a nighthawk hunt above a crop field and then veer across the highway; it was noon, the sky was clear and the temperature was 85 degrees F.

Common nighthawks roost on low branches, directly on the ground or on flat…

Castlewood Canyon

Rising on the Palmer Divide, Cherry Creek flows northward across the Colorado Piedmont and joins the South Platte River in downtown Denver. Along the way, the Creek has carved a scenic canyon through the mesa country of southern Douglas County. Now protected as a State Park, Castlewood Canyon is an excellent destination for hiking and nature study; the Visitor Center and primary entrance are on the west side of Colorado 83, several miles south of Franktown.

The Canyon, like mesas throughout the region, is capped by Castle Rock Conglomerate, deposited by the ancient South Platte River, which originally flowed eastward onto the High Plains just north of the Palmer Divide. An open forest of ponderosa pine cloaks the walls of the canyon, mixing with stands of juniper and scrub oak. Ten miles of hiking trails lead through the preserve, following the creek, snaking up the canyon slopes and meandering atop the rim; one loop crosses the old Castlewood Dam, constructed for irrigation purposes i…

Living in Wild Places

Not far from our farm, in Littleton, Colorado, is a new residential development called "Fox Haven." And it probably was before the houses were built, with their decks and privacy fences. Home builders know that many Americans like the feeling of living in the country and suburban developments are thus named accordingly. They also know that affluent Americans, while often very supportive of conservation organizations and recycling programs, don't want a recycled house; rather, they prefer the new models with all the latest features.

As a result, suburban sprawl continues, inner cities decay, long, congested commutes are the rule and wildlife habitat is destroyed. Of course, all towns, cities and farms were once wild areas and humans have some impact on natural ecosystems no matter where they live. Population control, development restrictions, open space protection and improved mass transit must all be part of the solution.

Long a poster child for suburban sprawl, Metro…

Night Winds

After reaching a high in the low 90s yesterday, we are sitting at 61 in Denver this afternoon. The change developed in the middle of the night as a period of strong north winds lashed the trees and rattled the window shades. That potent cold front encountered warm, dry air along the Front Range and no rain or snow developed. By early this morning, our temperature bottomed out at 44 degrees F.

Accompanied by the usual clear, sunny skies, the cool air was just right for yard work, certainly more comfortable than the heat of yesterday afternoon! As the front moved eastward, tied to a low in central Montana, we experienced a brief period of "upslope" late this morning; the northeast winds forced air to rise across the topography of eastern and central Colorado, producing clouds and a few showers along the Front Range and north slope of the Palmer Divide.

By early afternoon, the wind had shifted from the northwest, down-sloping east of the Continental Divide and clearing out the sk…

The Chosen Species

Man is obviously not the largest or most powerful species on the planet. And, despite our slow maturation, a number of species have longer lives. Our sight is far inferior to that of raptors and the family dog has hearing and olfactory skills that are well beyond human capability. Many species outshine us when it comes to athletic talents (running, swimming, climbing, diving etc.) and almost all have survived the challenges of earth's ecosystems far longer than we have.

When humans first appeared, about 125,000 years ago, the Universe was almost 13.7 billion years old and the Earth was nearing 4.6 billion years of age. Though often ridiculed as a failed life form, the dinosaurs inhabited the planet for 160 million years and even some of Earth's current species (sharks and horseshoe crabs, for example) were present long before the first dinosaurs appeared. Next to humans, the youngest surviving mammal species is the Arctic fox, which has been around twice as long as humans.

But h…

A Cool, Bright Morning

Despite the crystal-clear sky and brilliant sunshine, it was rather cool along the South Platte this morning, with a temperature near fifty. But, if anything, the coolness seemed to increase wildlife activity across the floodplain.

Red-winged blackbirds and killdeer provided a steady background chorus while great blue herons, black-crowned night herons and double-crested cormorants moved along the river. A mother wood duck ushered her brood across a marsh-lined pond and a lone beaver cruised one of the larger lakes. A flock of cedar waxwings moved through the riverside woods and mixed squadrons of tree and barn swallows swooped above the floodplain, feasting on clouds of insects. Though we didn't find snakes on this cool morning, six-lined racerunners were abundant, scurrying into the leaf litter as we approached. Other sightings included yellow warblers, American kestrels, red-tailed hawks and a lone white pelican.

The highlight of the morning was a mother common merganser wit…

Tale of Two Fronts

We left Columbia this morning in warm, humid air, the temperature already in the mid seventies. Heading west into Kansas, the south wind intensified and dark clouds loomed on the western horizon. While the larger, more powerful storms stayed to our north (closer to the center of low pressure) the trailing cold front was clearly marked by a line of dark clouds, stretching from the northeast to the southwest. We crossed the front beneath this swath (just east of Salina), enduring a brief period of rain.

West of the front, the air was noticeably cooler and drier. A mild northwest breeze replaced the southern gale and the sky was soon cloudless. Brilliant sunshine illuminated the fields of central and western Kansas before a second front approached from the northwest. Like a distant range of mountains, the clouds towered above the High Plains and, as we grew closer, their dark underbellies shrouded the sky. Heavy rains developed west of Flagler, Colorado, but, thankfully, there was…

Fathers and Hope

Having evolved as hunters and protectors, human males are predisposed to violent behavior. Fortunately, the development of human culture has served to reign in this tendency but, as we all know, wars and violent crimes persist, almost always at the hands of men.

With Father's Day on the horizon, let's recognize that our best hope for ending this recurring cycle of violence lies with fathers themselves. Through their example, advice and influence, they have the best opportunity to direct their sons away from this innate behavior. On the other hand, their absence, emotionally and/or physically, significantly increases the risk of violent crime in these young men.

Life involves a series of choices and, without guidance, humans tend to follow their basal instincts. Fathers have both the duty and the opportunity to encourage their sons (and daughters) to make responsible decisions. They offer our best hope for a peaceful planet.

Man and Heat

As the season's first major heat wave envelops the eastern U.S., there will be many cases of heat exhaustion or heat stroke and, unfortunately, some heat-related deaths. Humans are more prone to heat-related illness than other animals for two reasons: we are intelligent and impatient.

Other animals are guided primarily by instinct. When excessive heat develops, they limit their activities, retreat to a cool den and wait for conditions to improve. Humans, on the other hand, are focused on time and take pride in a tough-minded approach to adversity. Unwilling to put off chores, reschedule events or demonstrate "weakness," they often remain active through the heat of the day, sometimes challenging nature by exercising in the face of extreme heat and humidity. "Just do it now" is their motto.

Of course, many heat-related deaths occur in individuals who are too frail or too young to care for themselves and, in those cases, other humans must accept responsibility. For …

Mountain Weather

This summer, many hikers and campers will head to the mountains, hoping to recharge their souls and to escape the heat of the lowlands. For their own health and safety, it is important that they are familiar with the challenges and fickle nature of mountain weather.

All other factors remaining equal, the temperature will fall 3.5 degrees F for every 1000 feet of elevation gain. In addition, high winds are common along mountain slopes, adding to the chilling effect of the altitude. On the other hand, the thin atmosphere increases direct warming from the sun and reduces protection from UV radiation. For all of these reasons, it is best to wear layers of clothing (including a waterproof parka) that can be adjusted through the course of the day; while staying warm is important, sweating will actually increase your risk of hypothermia should clouds or storms roll in. Obviously, sun screen and UV-protective sun glasses are also important equipment for any mountain excursion.

During the n…

Catalpas

The northern catalpas are blooming in Columbia this week. Natives of the mid Mississippi Valley, these trees are planted widely as ornamentals, primarily due to their showy, white flower clusters that appear in late spring. Rapid growers, northern catalpas may reach 100 feet or more and are easily recognized by their large, heart-shaped leaves. While they favor moist, well drained soil, they adapt to a wide range of soil conditions; in fact, we have a large catalpa on our farm in Colorado.

Southern catalpas, native to the Gulf Coast region, are smaller, topping out at 50 feet or so. Both species, though not in the legume family, produce long, narrow seed pods (up to 20 inches long) and have been known as Indian bean trees. Their wood, soft and brittle, is tolerant of moisture and has long been used for fencing and railroad ties; other uses include the manufacture of frames, furniture and bowls.

Catalpa worms, larvae of the catalpa sphinx moth, are the primary natural enemies of thes…

Genes, Experience and Luck

We are a product of three factors: genetics, experience and happen-stance; some might also include spirituality but I am inclined to lump that with experience.

Our genes determine our physical traits, our intellect and our talents; they also play a role in the development of our personality. In addition, genes confer a relative predisposition or immunity to various forms of disease, including pathophysiologic mechanisms related to the aging process.

Experience begins in utero and continues until the end of our life. It encompasses all of the influence that we receive from our parents, our family, our friends and everyone and everything that we encounter in our lives. Modified by our genetic makeup, this experience formulates our personality, our beliefs, our convictions, our interests and our lifestyle. These, in turn, affect our physical and mental health, our personal achievements and how we interact with the world around us.

Finally, happenstance can play a significant role in our lif…

Bully Birds

It was a calm, warm evening when I went out back to resume my novel. A Carolina wren sang from the far corner of the yard, a pair of chickadees moved through the redbud tree and a family of mourning doves huddled on a maple limb. Then, by page two, the starlings arrived!

Several pair of these despised immigrants flew into the yard, followed by their noisy, demanding youngsters. As the frenzied parents searched the shrubs and lawn for insects, their ravenous offspring watched from nearby trees, squawking incessantly. Though obnoxious by our standards, this aggressive behavior is inherent in their species and explains why starlings, introduced to North America in 1890, have now colonized most of the Continent.

Favoring cities, towns and farms, starlings nest in cavities, either in trees or in the sides of buildings. Often raising three broods in the course of a summer, they begin nesting earlier than many birds, occupying cavities that might otherwise be used by native species (such …

Kentucky's Knob Belt

Most of eastern Kentucky is covered by the Appalachian Plateau, its western edge angling from the northeast to the southwest and running just east of Maysville, Berea and Somerset. Capped by the Pottsville Escarpment of Pennsylvanian sandstone, this edge rises up to 500 feet above the Lexington Peneplain (the Bluegrass Region), which covers the north-central part of the State.

The boundary of the Peneplain and the Plateau is characterized by a chain of "knobs," dissected from the Plateau by stream erosion; these topographic remnants, which comprise the Knob Belt, parallel the margin of the Appalachian Plateau from Maysville to Berea, producing scenic vistas for the traveller and regional diversity for the naturalist.

Perhaps the best place to explore this Edge of Appalachia is at the Berea College Forest, off Kentucky Route 21, 3 miles east of Berea. Over 19 miles of hiking trails lead up and along the narrow ridgetops of the preserve, offering spectacular views into the adj…

Science and Entertainment

Like many people, I am fascinated by the weather and have been a regular patron of the Weather Channel for many years. Unfortunately, in recent years, the program seems to be more focused on entertainment than on the science of meteorology. And while they have certainly played an important role in keeping the public informed regarding dangerous weather conditions, they have, in my opinion, begun to devote too much time to documentaries and travelogues.

This week, with the onset of Hurricane Season, the Weather Channel has plenty of fodder for entertainment. Their field celebrities are no doubt packed and ready to be dispatched to threatened sites and, though I'm sure that none of them want any death or destruction to result from the storms, I'm also sure they're hoping for more excitement than the last two seasons provided. But, considering the station's focus on hurricane preparation and evacuation, it seems counterproductive and downright silly that they feel the need…