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Showing posts from July, 2007

January and July

Six months and two seasons apart, January and July trigger some of the same feelings in Midwesterners. While we savor the slow progression of spring and can't get enough of the sunny, cool days of autumn, we often tire of the summer heat and winter chill.

By late July, a month beyond the summer solstice, the daylight is waning but the hot, hazy weather is peaking. Looking ahead, we see the long stretch of August, offering little relief from the heat and humidity; we long for the cool, dry Canadian air of September. By late January, a month beyond the winter solstice, the days are noticeably longer. Nevertheless, we face February, with its cold, blustery days and ice storms; the balmy, fragrant days of March remain on hold.

On the other hand, when immersed in the soupy air of July, we long for the crisp feel of a mid winter day and, when bundled against the icy blasts of January, we dream of lounging in the thick, green summer grass. We are an inpatient species.

The Creationists

The prophets of Creationism, like the televangelists and infomercial salesmen, have found a receptive audience who will accept and pay for their product. Their flock of religious-minded, scientifically-naive Christians view the world through the narrow prism of their Bible, accepting a literal interpretation of Scripture. In their view, despite a wealth of scientific evidence to the contrary, the Earth is less than 10,000 years old.

Of course, science has been a threat to religions since their earliest years and many scholars have felt the wrath of the Church. Creationists are just the latest group to attack the advance of science, finding support from an uneducated populace and vote-hungry politicians. I suspect that these prophets are too intelligent to believe their own propaganda, but the money and prestige keeps them going. If we allow them to influence our educational programs, we will all be the poorer; religion has no place in the science classroom.

Monsoon

The summer Southwest Monsoon begins in Mexico as a dome of high pressure builds over that country; usually developing by June, the clockwise circulation around this dome brings in moisture from the Gulf of Mexico and the Gulf of California, producing intermittent heavy rains, especially across the central ranges. By early-mid July, this high pressure moves northward, into the southern Plains of the U.S.; reinforced by a heat-induced low over the Mojave and Sonoran Deserts, the moisture flow pushes into southeastern California, Arizona and New Mexico. By mid-late July, this monsoon moisture extends northward into Utah and Colorado; any instability related to fronts or upper air disturbances will trigger intense thunderstorms with torrential rain. The monsoon season generally lasts through August and may persist into September.

Monsoons, though generally thought of as heavy rains, are actually the changing wind patterns which produce conditions as described above; in fact, there are seas…

A Fruitful Year

Thanks to the deep snows of last winter, the heavy rains of spring and the lack of a late spring freeze, we have an abundance of fruit on our Colorado farm this summer. Other than the peach and apricot trees, which bloom in March (too early for this climate zone), our fruit trees are laden with their sweet bounty, a treat for us and the wildlife. Chokecherries, perhaps our most reliable fruit shrub, are drooping with their dark clusters; the crabapples, mulberries and pear trees are also very productive this year. Even the wild plums and apple trees, fickle providers, are loaded with fruit.

What we don't get to first (the great majority) will go to the wildlife. Raccoons, fox squirrels, skunks and field mice consume much of the bounty though birds get most of the chokecherries, mulberries and juniper berries. Robins, starlings, northern orioles, cedar waxings, blue jays, gray catbirds and northern mockingbirds are the common fruit-eating birds; western tanagers visit the farm …

Man and Climate Change

The current obsession with Global Warming, promoted and abused by a host of conservationists, politicians and business-minded entre-preneurs, is a product of real climate change, our human-centric view of the world and fear-based marketing. We often hear that "average temperatures are higher today than they have been in 10,000 years;" while this fact may be true, it must be viewed through the perspective of natural history.

The Pleistocene "Ice Age," which stretched from 2 million to 10,000 years ago, was just the latest of many glacial periods in the course of Earth's 4.6 billion year history. Furthermore, the Pleistocene was characterized by dramatic climate fluctuations; four periods of glaciation were separated by warm "interglacial periods," most of which lasted 10-20,000 years. Many (if not most) geologists believe that the Holocene, the Epoch in which we live, is just another interglacial period; since it began 10,000 years ago, we are likely in…

Pelican of the Plains

Mention pelicans and most Americans think of our southern coasts where brown pelicans doze on pilings or dive for fish in offshore waters. But another native species, the American white pelican, breeds on lakes of the Northern Plains and Intermountain West. Larger than their southern cousin, white pelicans have a wingspan of 9 feet and are easily identified by their orange bills and a black fringe on their wings. Watching them soar above the plains, the sun reflecting off their white plumage, is a stirring sight indeed.

Highly gregarious, American white pelicans gather in breeding colonies of several hundred to thousands of birds (often in the company of cormorants), choosing barren islands on relatively large lakes; since they nest on the ground, these sites offer protection from coyotes and fox. Two eggs are normally laid and are incubated by both parents; however, infant mortality is very high (often related to weather extremes and storms) and only one offspring is fledged by most …

Fade to Brown

Though we're only a month past the summer solstice, the landscape of mid America is taking on that burned-out look. Driving back to Colorado, the farmlands of Missouri were still verdant but it was a dull, faded green. Pale blue chickory lined the highway and mixed carpets of coneflower, yarrow and blazing star brightened some of meadows but most of the early summer wildflowers had gone to seed. Once in Kansas, only sunflowers brought color to the withering grasslands and, on the High Plains of western Kansas and eastern Colorado, only the wooded stream channels and irrigated cropfields were green.

While the abundant moisture of winter and spring is still evident in the shimmering ponds and healthy-looking trees, the intense sunshine, high temperatures, dry air and relentless winds quickly dessicate the topsoil and the grasslands fade to the dusty browns of fall. They may green-up briefly after heavy summer thunderstorms and early autumn rains but, for all practical purposes, t…

Sea Elephants

Sirenians (manatees and dugongs) are often called sea cows since they are the only totally aquatic herbivorous mammals. While whales and dolphins are closely related to cows, manatees and dugongs are subungulates, more closely related to elephants, hyraxes and aardvarks. They are thought to have diverged from a common ancestor back in the Eocene, some 50-60 million years ago, when one group began feeding on aquatic vegetation in the coastal shallows of Africa and southern Asia. Over thousands of years, the forelimbs of these creatures evolved into flippers, the body became streamlined, the hindlegs regressed and a flattened tail developed.

Numerous sirenian species developed by the Miocene (about 20-10 million years ago) but only one dugong species and four species of manatee survive today; dugongs are found in the tropical waters of east Africa, India, Indonesia and Australia, while manatees inhabit west Africa, the Caribbean, the Amazon Basin and tropical coasts of the Americas. …

Northwest Heat Wave

We generally think of Idaho and Montana as great places to escape the heat of summer. With their rugged peaks, glacial valleys, evergreen forests and rushing streams, they are the epitome of cool. Not this week!

A persistent high pressure ridge, which has brought severe heat to the Southwest all summer, has nudged its way into the Northwest, steering Pacific cold fronts up through British Columbia and down through eastern Saskatchewan. As a result, heat has been building from eastern Oregon through the western Dakotas all week, compounding the drought that has plagued this region for more than a year. Storms that develop over the mountains bring little relief, since the hot, dry air evaporates the rain before it reaches the ground; furthermore, these storms bring lightening, the primary cause of numerous wildfires across the region.

Too far north to benefit from the southwest monsoons of late summer, this area may have to await the early snowstorms of autumn to break the cycle of he…

Almost Canada

A piece of northern Canada covers a high, flat ridge in eastern West Virginia. Part of the Allegheny Front, the eastern edge of the Appalachian Plateau, this broad mountain hosts a boreal ecosystem, characterized by red spruce, alder, mountain ash, upland heath and sphagnum bogs. Though squarely in the Temperate Zone, the plateau's high elevation (averaging 4000 feet), blustery winds and copious precipitation (55 inches per year) have maintained the periglacial climate of the Pleistocene. Upslope storms from the east and west, dump up to 150 inches of snow on the summit from fall into spring.

Known as the Dolly Sods, this unique area is named for German immigrants, the Dahle family, who settled on the ridge in the 1800s; the term "sods" refers to the grassy clearings on which they grazed their sheep. Once covered with virgin, spruce forest, the summit is now a mosaic of woodlands, wet meadows and bogs; in addition to the plants mentioned above, visitors will find azaleas,…

Chesapeake Bay

The rivers of North America were molded by the Pleistocene glaciers and reinforced by their meltwaters. By the end of the Epoch, the massive Susquehanna River drained a large area of the eastern U.S.; with headwaters in south-central New York and northern Pennsyl-vania, this river and its numerous tributaries emptied into the ocean along the mid Atlantic Coast.

As the final Ice Sheets retreated into Canada, sea levels began to rise and, by 10,000 years ago, ocean waters had spead across the mouth of the Susquehanna. As the climate continued to warm and the glaciers continued to melt, the sea moved up the River's broad valley, creating Chesapeake Bay; the Bay stabilized at its current size about 3000 years ago, becoming the largest estuary in our country. Two hundred miles long and up to 35 miles wide, the Chesapeake has a shoreline of almost 11,700 miles and is home to more than 3600 plant and animal species; renowned for its blue crab, the Bay is inhabited by 350 species of fish.

D…

The Silurian Rim

Imagine a broad, shallow bowl of rock buried in the ground; you know that it is there because sections of its rim poke above the surface. This would be a good model of the Michigan Basin, centered on the lower Peninsula of that State. The rock bowl is composed of Lockport Dolomite, deposited in a shallow, Silurian sea, 420 million years ago; the rim itself is known to geologists as the Niagara Escarpment. The ground inside the bowl is younger than the rim, having gradually filled in with numerous layers of sediment; the ground immediately outside the rim is older, composed of Ordovician and Cambrian deposits.

As discussed in my Niagara Falls blog (July 12), that famous cascade has been cutting through the Niagara Escarpment for the past 12,000 years. From the Falls, the Escarpment curves north-westward across Ontario, Canada, and forms the Bruce Peninsula along Georgian Bay. Continuing westward, this Silurian rim of dolomite is exposed as Manitoulin Island and forms the southern coast …

From Flood to Feast

The Missouri River flooding of late spring and early summer created shallow lakes across its broad floodplain. Bringing silt and nutrients to the valley soil, annual floods are highly beneficial to the farmers who plant crops on this flat, fertile landscape.

Less fortunate are the fish that become trapped in its temporary pools. After several weeks of hot, dry weather, the flood-born lakes are rapidly receding and the stranded fish are dying by the thousands. Taking advantage of their plight, herons, egrets, mink and bald eagles snatch up the living while flocks of crows and vultures feast on the dead.

Such a macabre scene greeted visitors to the Eagle Bluffs Conser-vation Area, southwest of Columbia, this weekend. Hundreds of turkey vultures circled above the refuge while others strolled the muddy fields, enjoying a smorgasbord of rotting fish. Call it the circle of life; nature does not waste its bounty.

Messengers of Change

As the summer doldrums settle across the Midwest, that seemingly endless period of hot, hazy, humid weather, we often feel that nature's cycle has shut down. But, as usual, this perception arises from our own, narrow view of the world, tied as we are to our various habits and obligations.

In fact, the seasons continue to unfold and the first fall migrants are already moving south through the Heartland. Having bred on the Arctic tundra, some shorebirds depart for southern coasts by early to mid July; enroute, they stop to rest and feed on the mudflats and sandbars that line our lakes and rivers. Among these early travelers are least, semipalmated and pectoral sandpipers, which often mingle with the killdeer and spotted sandpipers that summer and breed in the Midwest.

While songbirds will not migrate until September and most waterfowl head south in October and November, migrant shorebirds grace our landscape from July through early November, usually peaking in number and variety by la…

Boston's Drumlins

Small, ovoid hills are common throughout eastern Massachusetts, especially in the vicinity of Boston. Viewed from the air, one sees that the long axis of these hills are aligned in the same direction (NW to SE), indicating that they were all formed by the same, large-scale process. These hills are drumlins, which typically occur in groups known as "drumlin fields."

Drumlins are composed of glacial till and form on the underside of a moving glacier. Aligned in the direction of the ice flow, they usually have a blunt northern (or ice-ward) edge and are tapered toward the south (or lee side). While the exact mechanism of their formation is a subject of ongoing debate among geologists, all agree that the drumlin fields of New England, Canada and the Northern Midwest are remnants of the Wisconsin Glacier, which scoured the region from 60,000 to 12,000 years ago.

Those in the Boston Area include Bunker Hill, Breed's Hill, the Blue Hills (south of the city) and the numerous i…

Beetles

Beetles are the most diverse group of animals on Earth. Of the 1.2 million species of animal known to science, 75% are insects; since 40% of insects are beetles, it follows that 30% of all animal species are beetles!

Members of the Order Coleoptera, beetles have chewing mouthparts and four wings; the dorsal wings are thickened and covered by a hard, keratin surface. Highly variable in color and habitat, some beetles are aquatic (whirligigs are among the best known) but most are terrestrial. All undergo complete metamorphosis, from egg to larva to pupa to adult, and may overwinter in any form (depending on the species). Some beetles lay their eggs in the soil while others deposit them on vegetation or plant debris. Larvae come in a variety of shapes and sizes but almost all have voracious appetites and often cause significant damage to plants. Unless the beetle overwinters in a pupal state, this stage is usually brief, soon morphing to the familiar, adult form. With life spans of a mont…

Niagara Falls

One of the most famous natural landmarks in North America, Niagara Falls is a relatively recent addition to our country's topography. As the Wisconsin Glacier plowed into the Upper Midwest, 60,000 years ago, it scooped out the broad basins of the Great Lakes. And, as the last Ice Sheet melted back into Canada, some 13,000 years ago, these basins began to fill with meltwater, expanding well beyond their current size. Eventually, governed by glacial deposits and a rebounding crust, the Lakes drained northeastward, through the St. Lawrence Seaway.

The Niagara River, which connects Lakes Erie and Ontario, meadered across soft, glacial sediments when it first formed; by 12,500 years ago, its channel encountered the edge of the hard, Lockport Dolomite, the uppermost layer of the Niagara Escarpment. This resistent bedrock, initially deposited in a Silurian sea (some 420 million years ago) abutted softer sediments to its north; these younger rocks were more easily eroded by the increasingl…

Birdwatchers

As a birder for more than 30 years, I have come to realize that we are a heterogenous group. Passive birdwatchers, such as my mom, simply enjoy watching the backyard birds; they know a handful by their proper names but refer to most as "those little yellow ones" or "that big one with the long beak." These birders usually buy their feeders and seed at the grocery store (or at Walmart) and have no use for binoculars. Casual birders, on the other hand, can identify a dozen or more of our common birds, generally have a pair of binoculars and buy their feeders and special seed blends at bird specialty stores.

Social birders are members of the Audubon society and local birding groups. Equipped with the latest birding gear, they take part in bird counts, bird walks and birding seminars. They also maintain a "life list" of the birds they have seen and are among the most common patrons of the ecotourism industry. Naturalist birders, with whom I identify, enjo…

Armored Immigrants

More than 150 years before the Bush Administration established the Homeland Security Administration and began to wall off our southern border, a group of armored Mexicans slipped across the Rio Grande River. Gaining a foothold in southern Texas, these foreign nationals spread throughout most of the State by the early 1900s, moving into Louisiana, Arkansas and Oklahoma over the next few decades. Today, they have been seen as far west as New Mexico, as far east as the Gulf Coast States and as far north as southern Kansas and south-central Missouri.

While not terrorists, nine-banded armadillos have surely torn up gardens and farmland with their propensity to dig. Using their clawed feet to create a network of burrows, armadillos favor moist rocky woodlands and prairie stream valleys; they avoid wetland areas, where a high water table tends to flood their dens. Covered with overlapping, boney plates from heat to tail, these small mammals have poor eyesight but are equipped with an excellen…

Road to the Sky

The Mt. Evan's massif looms west of Denver, connected to the Continental Divide by the Guanella Pass ridge. This magnificent Wilderness is accessed by numerous trails and jeep roads; for less adventurous visitors, a paved toll road (Colorado 5, the highest in the U.S.) begins at Echo Lake (elevation 10,600 feet) and winds to a parking area just below the summit of Mt. Evans. This peak, the highest along Colorado's Front Range and the 13th highest in the State, tops out at 14,264 feet. Echo Lake is best reached by taking Exit 240 from I-70 (at Idaho Springs) and heading southward and upward along Colorado 103. If possible, plan your visit for a weekday and arrive in early morning to avoid the frequent afternoon thunderstorms; Colorado 5 is generally open from June through early September.

On your way up Colorado 5, stop at the Mt. Goliath Bristlecone Pine Area, which sits at timberline. In addition to exploring some of the oldest living plants on Earth, you will have a good…

Mimosas

The mimosas are blooming in Columbia, a week later than usual. A member of the legume family, which includes acacias, mesquite, redbuds, paloverde and locust trees, this small, tropical-looking tree is native to southern Asia, from Iraq to Japan. Introduced to North America in the mid 1700s, mimosas (also called silk acacias), adapt to a variety of soils and have become naturalized in parts of the Southeastern U.S. and southern California.

Mimosas are easily identified by their lacey fronds and fluffy, pink flowers; the latter, which adorn the tree from late June through August, attract bees and hummingbirds. Elongated seed pods, typical of most legumes, ripen by late summer but often remain on the tree through the winter, awaiting the warm, moist soil of spring; this prolific tree also spreads by suckering and, when conditions are favorable, dense stands may develop.

Live Earth Follies

The Live Earth extravaganza is occuring across the globe today, organized with the goal of raising awareness about the Global Warming Crisis. With all due respect to well-intentioned participants, anyone who is still unaware of that issue will not likely respond to the program's message.

Furthermore, man's role in global warming is directly tied to his consumerism and there are no better examples of that vice than the entertainment industry stars, with their multiple mansions and private jets. As they say, talk is cheap. Al Gore, who has garnered a new (and no doubt lucrative) career from this issue, would get more respect from true environmentalists if he downsized his home, traveled the country in a hybrid vehicle and gave up the star-studded galas.

My cynicism notwithstanding, I concur with the importance of this issue, especially as it relates to our impact on Earth's ecosystems. But young people are more likely to be attentive to such matters if they are raised by paren…

Desert Heat

After hearing about the extreme heat across the Desert Southwest over the past week, one might wonder why we never see similar temperatures in Florida. There are multiple reasons why tempera-tures of 110F or above are generally limited to desert areas.

Deserts develop in regions with sinking air and/or where regional mountains create both rain shadows and downslope winds. As air sinks, it compresses, dries out and heats up. Dry air is more dense than humid air and is thus capable of reaching higher temperatures. Adding to these factors, deserts are often cut off from precipitation by mountains on their windward side; rain and snow are minimal and cloudless skies intensify the solar heating. Lack of precipitation also leads to sparse vegetation, causing the rocks, soil and concrete to absorb heat through the day, radiating it back to the lower atmosphere day and night.

When local weather patterns remain stable for an extended period, the heat can build to levels we have seen this week (h…

The Hawaiian Ridge

Mention Hawaii and most of us think of a handful of Pacific Islands known for their fabulous weather, lush vegetation, big waves and volcanoes. In fact, these are the eastern end of a chain of 137 islands, islets and atolls that stretch for almost 2000 miles across the ocean. Trending southeast to northwest, they represent the summits of an underwater, volcanic range, a 40 million year product of the Hawaiian hotspot, now located under the Big Island.

The hotspot has remained nearly stationary for the last 80 million years as the Pacific Plate has moved over it. Initially, the plate moved northward, producing a volcanic range that has since eroded into the Emperor Seamounts, now stretching north from the west end of the Hawaiian chain. About 43 million years ago, the Pacific plate changed to a northwest heading and, in concert with the hotspot, produced the Hawaiian Ridge, composed of numerous volcanoes. Midway, 27.7 million years old, is a summit near the west end of the ridge wh…

Freedom

We Americans are frequently reminded (especially on the Fourth of July) that we are citizens of the most free country on Earth. But freedom is a relative term and our definition of freedom may not be shared by other cultures.

In animal societies, behavior is governed solely by instinct. The process of natural selection favors traits and behaviors that will insure the survival of that species and these become imprinted within their genetic code. Humans, on the other hand, being more sophisticated and conniving creatures, must be governed by societal laws, established to protect the rights and freedoms of society as a whole. While we can all agree that many of these laws are appropriate, outlawing behavior such as robbery and murder, others are more controversial. The freedom to have an abortion vs. the push to criminalize the "murder" of fertilized eggs is one of our more politicized battles. So is the freedom from violence vs. the freedom to collect AK47s. At times, it is ha…

The Universal Language

While insects, birds, amphibians and whales were singing long before man evolved, early humans also used music as a means of commu-nication and as an important component of their rituals. And though we've since dispersed across the globe and developed hundreds of unique languages, music continues to tie us together. Regardless of our culture, music has a way of touching our collective human soul, evoking similar emotions in all of us.

Of course, we all have our favorite forms of melody and percussion but it is the rare human who doesn't enjoy some type of music. I, for one, can't get through the day without a few periods of musical relaxation, one of my favorite means of stress reduction. For our human family as a whole, music will remain the universal language, spawning hope that our many artificial barriers may someday disappear.

Lake Agassiz

As the last Pleistocene Ice Sheet retreated into Canada, 13,000 years ago, a large meltwater lake filled a broad, flat, glacial basin along the North Dakota-Minnesota border. Soon filled to the brim, the lake spilled southward over the glacier's terminal moraine, draining into the Minnesota River. Continually filling in behind the shrinking Ice Sheet, the lake spread northward across southern Manitoba and, by 11,000 years ago, began draining into the Great Lakes chain. At its peak, this meltwater lake covered 365,000 square miles, an area larger than the State of California, and is renowned as one of the largest freshwater lakes in the history of our planet.

Named for Louis Agassiz, a famous Swiss geologist, Lake Agassiz eventually covered most of Manitoba, eastern sections of Saskatchewan, western Ontario, eastern North Dakota and northwestern Minnesota. By 8000 years ago, the Wisconsin Glacier had retreated far enough to allow the lake to drain northward, into Hudson Bay. Th…

Wonderland

In the summer of 1960, the year that I turned ten, two friends and I decided to clear a trail into the woods that bordered our Cincinnati neighborhood. Armed with an assortment of tools from our parents' garages, we started early in the day and, by late morning, were out of sight of our familiar surroundings. Somewhat intimidated by this separation, I recall that we considered abandoning the project more than once.

Nevertheless, we returned to the trail after lunch and steadily approached a low rise in the forest floor. Soon after crossing this ridge we heard a faint rumble in the distance and, within another twenty yards or so, recognized the sound as flowing water. Angling our trail toward the sound, we soon arrived at the edge of a deep gorge, a landscape that none of us had ever seen before. Awestruck, we worked our way along the rim of the chasm until we found a safe route to the bottom.

There we found a wonderland of limestone boulders, shallow pools, waterfalls and jungle-lik…