Sunday, September 30, 2007

Dogs and Nature

As a dog owner for most of my life, I certainly appreciate the affection that humans have for their dogs. Domesticated 12,000 years ago, dogs have been far more than faithful companions, often playing important roles in hunting, security, livestock control and direct human assistance. But dogs, unlike their wild ancestors, are no more part of nature than are domestic chickens, cows or pot-bellied pigs. In fact, since dogs have been bred for their special talents and desired appearance, humans are more natural than their canine companions.

Most dogs need plenty of activity and, due to their inate instincts, can be a problem in fragile ecosystems, often chasing native wildlife and disturbing the sensitive flora. While parks, farms and non-vital open space areas are reasonable sites for off-leash exercise, most nature preserves and wilderness areas either exclude dogs or require that they be leashed and that their excrement be packed out. Unfortunately, as one who often visits such areas, I have found that a significant percentage of dog owners ignore those regulations; for this reason, it seems to me that dog exclusion is the only viable alternative. Our love for dogs cannot outweight our commitment to conservation!

Saturday, September 29, 2007

A Hint of Color

Driving down to the Lake of the Ozarks today, the fading greens of the September landscape were still dominant, broken only by the yellow of goldenrod, the light purple of asters, the orange-red of sumacs and the ubiquitous billboards along Missouri's highways. But there were also hints of autumn in the woodlands, where patches of olive and rust dappled the forest.

As the length of daylight wanes, chlorophyll production is shut down and the underlying leaf pigments begin to show through. While yellow pigments are present in most leaves, the reds, oranges and purples, which protect the chloroplasts from ultraviolet light, vary among plant species. Sunny conditions increase the production of these pigments and, combined with cool nights (which diminish pigment withdrawal), tend to yield the most striking autumn displays.

In central Missouri, fall colors generally peak during the third week of October. This year, since drought stress continues, the autumn show may develop early as trees discard their leaves to conserve water.

Friday, September 28, 2007

Georg Steller

To naturalists, the name "Steller" evokes images of northern forests, rocky shorelines and cold Pacific waters. Born in Germany, Georg Wilhelm Steller was trained as a zoologist, botanist and physician. After accepting a position at the Academy of Science in Petersburg, Russia, Steller was chosen to be the naturalist for Vitus Bering's exploration of the northern Pacific, a journey to chart a passage to North America.

Bering and his crew reached Alaska in 1741 and, along the way, Steller compiled a long list of newly discovered plants and animals. Among the latter were sea otters, northern fur seals, Steller's sea cow, Steller's sea lion, spectacled cormorants, Steller's eider, Steller's sea eagle and Steller's jay. The sea cow, a giant dugong weighing up to three tons, was soon famous for its meat and hide and was hunted to extinction within thirty years; spectacled cormorants also disappeared within a century of their discovery. Steller's sea lions, though holding on, have diminished in number over the past few decades; while the cause remains uncertain, there is evidence that overfishing in the northern Pacific has forced these sea lions to consume a less nutritious diet, leading to a rise in infant mortality.

Georg Steller died in 1746 before his journals were published but lives on in the plants and animals that bear his name. Today, young naturalists might assume that such monumental voyages of discovery are relegated to history but there is still much to explore and document: the rain forests, deep sea and outer space beckon!

Thursday, September 27, 2007

Colorado Gold

While gold nuggets brought prospectors and settlers to Colorado in the mid 1800s, gold leaves are what bring back many visitors each year. Peaking in late September, the annual aspen display, set against a background of evergreens, snow-capped peaks and a deep blue sky, provides a spectacular setting for hikers and photographers alike. Recommended viewing areas near Denver include Berthoud Pass (U.S. 40), Kenosha Pass (U.S. 285) and Squaw Pass (via Colorado 103, south of Idaho Springs).

Quaking aspen are the most widely distributed of native, North American trees, found across the upper latitudes of the Continent and southward along the Appalachian, Rocky Mountain and Sierra Nevada Ranges. Not tolerant of excessive heat or drought, aspen are limited to higher altitudes in the West, where they grow along drainages at elevations of 8500 to 10,500 feet. They spread by seed and by suckering; the latter produces colonies of aspen with their own unique color, ranging from pale yellow to bright orange during the autumn display.

Aspen are successional trees which develop in areas where the coni-ferous forest has been opened up by wildfire, avalanches, storms or human activity. Though they may reach 60 feet in height, these deciduous trees are eventually shaded by a new growth of spruce and pine, causing them to die back and wait until the forest opens once again.

Wednesday, September 26, 2007

The Early Ducks

Blue-winged teal and their western cousins, the cinnamon teal, are the first North American waterfowl to begin their autumn migration. By late summer, these small, attractive ducks begin to gather in flocks and soon congregate along their primary flyways.

While blue-winged teal are common throughout most of the U.S. and southern Canada, cinnamon teal are primarily found west of the High Plains; where their range overlaps, these two species have been known to interbreed. Teal favor shallow wetlands and are best found in backwater areas, marshes or flooded fields. Most abundant in the Heartland from late September through mid October, blue-winged teal winter along the Gulf Coast, from Florida to Mexico; most of the cinnamon teal winter in California.

Unlike their fair-weather cousins, green-winged teal breed in Canada and winter on open lakes and rivers throughout the U.S.

Tuesday, September 25, 2007

Salmon Farms

On our last day in Vancouver, an article in the Globe and Mail explored the controversy surrounding salmon farming in British Columbia. Initially met with enthusiasm by the conservation community, the small, experimental farms of the 1970s seemed to provide an answer to the decimation of the wild salmon population. But, as the farms have become large, mechanized facilities, a number of environmental concerns have been raised.

Canada ranks fourth in salmon aquaculture, behind Norway, Chile and the U.K., and about 60% of its farms are in British Columbia. Though some of the B.C. facilities raise Pacific salmon, most have switched to Atlantic salmon which adapt better to the aquaculture environment and tend to grow faster. The newest facilities can handle almost 1 million fish, adding to concerns about local pollution and the spread of disease (especially sea lice). In addition, since most of these farms use netting for containment, schools of salmon often escape, raising concerns that they will spread disease to wild populations and compete with the latter for food and spawning sites.

A potential solution to these environmental threats is the development of solid-wall holding tanks which will permit filtration of the sea water, provide a mechanism for waste control and eliminate the risk of escape. Of course, such structures would cost more to build and operate, increasing the market price of farm-raised salmon. Whether consumers will accept the cost of environmental protection is another matter.

Monday, September 24, 2007

Science and Legend

During our visit to Vancouver Island, we took a boat tour of the Broken Islands National Park, south of Ucluelet. Though marketed as a wildlife tour (whales, sea lions, black bears, eagles), our guide was also very knowledgeable about the region's history and related the native tribe's legend of how the Broken Islands came to exist.

According to their legend, the bay area was once covered with solid land and a large river cut across the plain to the sea. Their god became angry with the tribe and pounded his fist into their territory, breaking the plain into islands and forcing the natives to scatter throughout the archipelago.

When man first reached the Northwest, about 20,000 years ago, much of North America was covered with glacial ice and the sea level was much lower. No doubt, most, if not all, of the Broken Islands were then part of the mainland, forming high points on a wide, coastal plain. Then, 12-15,000 years ago, the glaciers began to retreat, the sea level rose and these areas of higher ground became islands. Today, this scientific knowledge unlocks the basic truth of that native legend.

Birding the Island

Despite the spectacular scenery, fair weather, varied habitats and interesting mammals, my birding experience on Vancouver Island was somewhat disappointing. Perhaps it was the season, the brevity of my visit or pure bad luck. More likely, used to birding in Colorado, the Midwest and Florida, there are just not as many bird species in the cool, damp Northwest.

Crows, ravens and gulls dominated the scene; among the latter were ring-billed, herring, glaucous-winged and mew gulls. Cormorants were also fairly common along the rocky shore and I spotted a few Pacific loons on the Strait of Georgia. Otherwise, marine birds were limited to a single bald eagle, a couple of ospreys, a flock of surf scoters off the west coast of the island and a few black oystercatchers among the tidal pools. Beach birds were represented by crows, gulls and scattered flocks of savannah sparrows.

Birding in the rainforest was especially challenging. While songbirds chirped from the canopy, they were almost impossible to see from the ground. An occasional woodpecker (pileated, hairy or red-breasted sapsucker) moved among the towering trunks and a few red-breasted nuthatches circled up the moss-covered giants. Winter wrens and golden-crowned kinglets hunted in the understory but were more often heard than seen. Only the raucous Steller's jays, which favored the clearings and border zones, were easy to observe.

Sunday, September 23, 2007

Vancouver Island

Like the many other exotic terrains that, collectively, make up the western portion of North America, Vancouver Island drifted in on oceanic crust and welded itself to the Continental Plate. Geologists believe that Vancouver Island actually originated in the Southern Hemisphere (having rifted from another land mass) and arrived in the Pacific Northwest millions of years ago. During the Pleistocene Glaciations, when sea level was significantly lower, a land bridge connected the island to the mainland of British Columbia, permitting wolves, black bears, cougers and other fauna to colonize its varied habitats.

Today, Vancouver Island is an exciting destination for naturalists and outdoor sportsmen. A rugged mountain range bisects the Island, wringing copious moisture from storm fronts that push in from all directions. Such weather conditions have fostered the development of a rich, Temperate Rainforest, characterized by huge western red cedars, fir and hemlocks, which rise above an understory of blueberry, huckleberry, ferns, horsetails and other moisture-loving plants. Scenic, rocky shorelines, tidepools and sandy beaches line the undeveloped coasts, attracting a wide variety of sea birds and marine mammals.

Migrating whales (humpback, grey, minke), orcas and dolphins feed in the numerous bays while Steller's sea lions and harbor seals lounge on rocky islets. Sea otters, once extirpated by overhunting, are making a slow comeback and are occasionally spotted in kelp beds along the western coast.

Earth from the Air

A trip to British Columbia kept me away from my blog for the past week but, as do most vacations, gave me plenty of topics to discuss. Flying to Vancouver from Denver, our route took us northward along the Front Range of the Rockies and then northwestward over the stark landscape of Wyoming's high desert, with its sharp hogbacks, numerous escarpments, broad basins and incised stream beds. Further north, we crossed the glacier-studded crest of the Wind River Range and were soon treated to a spectacular view of North America's most famous fault-block mountains, the Tetons. But the most amazing scene lay further ahead: the rugged, knife-edged summits and deep, narrow canyons of the Sawtooth-Bitterroot Ranges, which stretch along the Idaho-Montana border. To think that early explorers, including Lewis and Clark, managed to cross this forbidding wilderness with canoes and horses is a testament to their skill and perseverance; it is surely the most imposing landscape that I have ever seen from the air!

I love to fly and, unlike most mature adults, I prefer a window seat. For me, the chance to view Earth's landscape from 30,000 feet is always a rewarding experience. There is no other way to truly appreciate the breadth of her floodplains, the majesty of her mountains and the intricate pattern of her canyons. And for those of us who have an interest in geology, there is no better way to witness the interplay of rock formations, faulting, uplift and erosion that have sculpted the face of our planet.

Saturday, September 15, 2007

Red Banners of Fall

Among the earliest of fall colors are the bright, orange-red banners of the sumac, which often begin to brighten the landscape by late August (earlier in years of drought). Staghorn and shining sumacs are the most common species in North America, native to southern Canada and most of the eastern and central U.S. Tolerant of dry, rocky soils, these small trees spread by seed and by suckering, often forming dense stands on south-facing slopes. Though considered a weed tree by most foresters, the reddish fruit clusters of these sumacs provide food for many songbirds and small mammals.

Sumacs are easily transplanted and are often used to add diversity to border areas or to naturalize fence lines. Their open, branching form allows gardeners to plant them behind lower shrubs and wildflowers. Of interest, American smoketrees, cashews and pistachios belong to the sumac family.

Friday, September 14, 2007

Shifting Pressure

Since the massive earthquake off northwestern Sumatra triggered a deadly tsunami in December, 2004, a series of 20 or more major quakes have occured in the region, accompanied by hundreds of aftershocks. As one might expect, these seismic events are interrelated.

The islands of Sumatra and Java form the western side of the Indonesian Archipelago and sit atop the western edge of a southern extension of the Eurasian Plate. Just off their western coasts, the Australian Plate is sliding beneath the Eurasian Plate; in such subduction zones, tremendous friction develops between the Plates. As the pressure builds, the edge of the upper plate (in this case the Eurasian) is warped downward; eventually, the warped edge will rebound upward, break off or induce a fracture in the lower plate. Any of these scenarios will produce an earthquake and, depending upon the size and depth of the rupture, a tsunami.

While an earthquake follows a release of pressure at one point along the subduction joint, it also portends a buildup of pressure further down the line. This series of transmitted pressure, release events and associated earthquakes is what we have seen along Indonesia over the past three years. Though the timing of the next major quake remains uncertain, it will occur and another tragic tsunami could result.

Thursday, September 13, 2007


As I have discussed in previous blogs, I prefer conservation areas and other naturalized preserves to the people-friendly environment of nature centers and State Parks. Wildness and solitude are more inviting to me than manicured trails, comfort facilities and crowds.

One of my favorite areas in central Missouri is the Davisdale Conservation Area, northeast of Boonville. Stretching across and atop the north wall of the Missouri River Valley, this 2700 acre preserve is a mix of forest, wooded meadows, crop fields and wetlands. Stream channels provide topographic relief and a number of old farm ponds add to the natural diversity. Access to this appealing retreat is via a network of graveled roads and foot trails.

As one might expect, this large area, stitched together from abandoned farms, attracts an excellent variety of wildlife. Those who visit early or late in the day have a good chance of seeing white-tailed deer, red fox, raccoons and the occasional coyote. The open country of Davisdale is especially good for raptor viewing; red-tailed hawks, great-horned owls and American kestrels are common here throughout the year, joined by rough-legged hawks in winter. Of course, a wide variety of songbirds, reptiles and amphibians also inhabit the refuge and there is no better time to visit than the mild, sunny days of early autumn.

Wednesday, September 12, 2007

A Deluge of Records

Several decades ago, we received our weather reports from a local radio or TV celebrity. On occasion, after an especially hot day or frigid night, we would learn that our city set a record for the date. Today, kept informed by a 24-hour Weather Channel and their cable competitors, we are inundated with reports of weather records from across the country and around the globe. This wealth of "bad news" results from two factors: the need to fill 24 hours with entertaining weather news and, most importantly, computerized records.

The latter allows our weather entertainment industry to "pull-up" all sorts of creative records by accessing their computerized archives. Those who tune into their station are presented with a host of new records everyday; we learn that one city has "set a record for consecutive days without precipitation" while another has "broken its record for the number of record low highs for the month of March." Though no doubt factual, this deluge of record weather phenomena leaves many viewers wondering if our planet's weather has gone haywire; perhaps these are clues to an impending global catastrophe.

Backed by the reality of climate warming, these minicrises, add to a sense of doom which is further stoked by an increasing number of "weather disaster" series. Like evangelists, weather entertain-ment gurus know that a healthy dose of fear keeps the faithful in touch (and patrons mean money).

Tuesday, September 11, 2007

Fall Arrives

Though the autumn equinox is still almost two weeks away, fall has arrived in Columbia. Yesterday, after a mild morning, steady north winds developed by noon, the sky clouded over, intermittent showers occured and the temperature gradually dropped into the upper sixties. Overnight, the low reached 50 degrees and today's high should remain in the low seventies; a similar range is forecast for the rest of the week, the first cool stretch since May.

While the seasons are officially marked by the solstice and equinox dates, these are purely astronomical events. And though these events are tied to the solar cycle and are directly related to the root cause for our seasons, nature does not adhere to a strict calendar. Rather, nature's seasons are defined by gradual progressions, with many false starts and setbacks along the way. In some years, fall-like weather arrives by late August while, in others, hot, humid conditions persist into October. Though seasonal patterns may be predictable, nature keeps us guessing most of the time.

Monday, September 10, 2007

Garter Snakes

Well known to naturalists and gardeners, garter snakes are the most common and widespread snakes in North America. Represented by fours species in Missouri, they favor open woodlands with rocky outcrops and nearby streams or ponds and are often found in residential areas. While they may bite to protect themselves, these beneficial snakes are not poisonous.

Garter snakes breed in spring and females deliver nine to twelve fully-developed young in late summer. As the nights begin to cool, these reptiles bask on logs or rocks during the mid-morning hours, warming up before they go hunting; September is thus a good month to look for them. Their prey includes insects, earthworms, tadpoles, frogs, eggs, nestlings and a variety of small mammals. Like most snakes, garters shed their skin on a regular basis, breaking it open along their snout and, after snaring it on the edge of a log or rock, literally crawl out of it; some birds (great-crested flycathers) and small mammals use the skins for nesting material.

By mid November, garter snakes begin to congregate in underground burrows or south-facing dens, where they often overwinter in groups of a hundred or more.

Sunday, September 9, 2007

Sierra Madre Monarchs

American naturalists have long recognized that monarch butterflies migrate southward in the fall but they had no idea whether they wintered somewhere or simply laid their eggs and died out along their journey. Then, in 1975, huge congregations of monarchs were discovered in the Sierra Madre Mountains, west of Mexico City. Twelve wintering sites were discovered, all in pine forests near an elevation of 9000 feet; within these colonies, naturalists documented monarch concentrations of up to 4 million butterflies per acre. We now know that virtually all monarchs east of the Rocky Mountains winter in this area, leaving the species vulnerable to cold weather spells, regional pollution and local logging activity.

Monarchs that survive the winter breed in March and the migrants that we observe in spring represent a mix of last autumn's adults and younger generations. Why such small, fragile creatures make such a long journey to congregate in such a limited area remains a mystery.

Saturday, September 8, 2007


Despite their value to gardeners, fruit growers and arborists, cuckoos are unknown to most Americans; only birders and naturalists are familiar with these jay-sized, curve-billed, long-tailed summer residents. Yet, their appetite for hairy caterpillars (including tent caterpillars), eschewed by most birds, helps to protect natural and agricultural plants alike.

Yellow-billed and black-billed cuckoos are fairly common summer residents throughout most of the U.S. and southern Canada; the black bills are more common in the north, while the yellow bills dominate across the southern States. A third species, the mangrove cuckoo, is found along the coastal areas of southern Florida. All three of these cuckoos favor dense foliage along streams and inlets and are more often heard than seen; their calls, distinct for each species, are characterized by repetitive series of monotone notes.

In my experience, black-billed and yellow-billed cuckoos are most often encountered in residential areas during September or early October. Leaving their summer haunts, they begin to roam about open woodlands, feasting on a variety of caterpillars and preparing for their journey to the south; they will winter in South America.

Friday, September 7, 2007

Lunar Seasons

Current scientific evidence suggests that the moon formed 4.5 billion years ago when a small planet collided with the Earth. This collision ejected molten debris (which coalesced into the moon) and produced a tilt in the Earth's axis. Since that time, the gravitational pull of our lunar satellite has kept the axis tilt in place, ensuring that our seasons unfold in a steady, predictable pattern. Were it not for this stabilizing effect, Earth's axis would wobble, the seasons would have abrupt, unpredictable changes and higher life forms may never have evolved.

Well before the scientific era, man relied on the lunar cycles to mark Earth's seasons. Now, with our advanced technology and ubiquitous calendars, the moon has become more of an aesthetic or romantic symbol for most of us and we take its presence for granted. But our more primitive ancestors knew better: the moon gives us our seasons.

Thursday, September 6, 2007

Craig's Crime

The recent political turmoil surrounding Senator Larry Craig of Idaho highlights the hypocrisy that pervades our Government and our society. Caught in an apparent act of homosexual solicitation, Craig became an immediate embarrassment for his colleagues in the Right Wing of the Republican Party, the bastion of intolerance. The Senator did not kidnap or rape anyone and he did not solicit a minor. Rather, frustrated by his own repressed urges, Craig was seeking a brief, clandestine encounter. As one who led a crusade against homosexual rights and spearheaded the attempt to impeach President Clinton for his sexual affair, this staunch Conservative could not risk a more open homosexual relationship.

The Christian Conservatives of America pride themselves for their protection of family values. Yet, time and again, we find that they are just as human as the rest of us. Homosexuality is an inborn trait, not an irresponsible choice. We cannot abolish it with laws and self-righteous political organizations. Scientific studies have shown that 10-15% of humans are homosexual or bisexual and we are all aware of the high rate of heterosexual infidelity. Members of the Christian Right are just as likely to be gay or to have extramarital affairs as the rest of society; those who are most openly intolerant are most likely to have something to hide.

Wednesday, September 5, 2007

A Record Setting Trio

When Felix slammed into Nicaragua and Honduras yesterday, it was the first time in recorded weather history that two category 5 hurricanes made landfall in the Americas in the same year. And, since Henriette was also strafing the Baja Peninsula, it was the first time that hurricanes were landing on both the Pacific and Atlantic Coasts of North America on the same day.

While the latter may be considered a mere coincidence, the coupling of Hurricanes Dean and Felix, two category 5 storms within two weeks, is more likely a reflection of our warming climate; this record may not last for long! Warming sea temperatures favor both the development of tropical storms and the formation of larger, stronger hurricanes. Though year-to-year hurricane forecasting is still a guessing game, the projection that, over the coming decades, we will experience more frequent and more powerful storms, is likely a safe bet.

No word yet from Pat Robertson on who God was punishing with this recent trio of hurricanes.

Tuesday, September 4, 2007

Twilight Spectacle

Those of us who have been wildlife watchers for many years usually know what to anticipate when we head outdoors at any given time of year. But it is the occasional unexpected discovery that stokes our ongoing enthusiasm. One such event occured last evening.

At 7PM, I went outside to put away a few tools and, just as I exited the back door, a common nighthawk swooped through the yard. Used to watching them hunt well above the treetops (see my Blog of 9-1-07), I was surprised by its low level foray. But this mild shock soon became full-bodied awe as I watched a large scale aerial attack take place 20-30 feet above the ground. Nighthawks were swooping in from all directions, strafing the roofline and veering among the trees. Like a squadron of fighters, they darted above our property, made a quick change of course and sailed back in from a different heading. At least 20 of these agile hunters seemed to be involved in the attack, which continued for half an hour.

The reason for their frenzied behavior was soon apparent as a swarm of dragonflies moved overhead, zigzagging in response to the nighthawk maneuvers. Dragonfly swarming, most often seen in September, is a documented but poorly understood event; whether it represents a true migration, a dispersal of regional populations or a response to high prey concentrations remains an open question. In this case, the swarm obviously attracted the attention of a migrating flock of nighthawks, offering an easy target and plenty of nourish-ment for their journey to the south.

Monday, September 3, 2007


Often called daddy longlegs or haymakers, harvestmen are most often encountered in late summer or early fall. Most hatch from eggs in the spring but remain secluded for much of the summer, searching the leaf litter or wood piles for smaller insects; they also feed on carrion and fallen fruit. Resembling spiders with their bean-sized body and eight long legs, harvestmen are, in fact, insects.

Roaming about in late summer, they are potential prey for birds, mice, shrews and lizards; others are caught by human children who can't resist pulling off a leg or two. Fortunately, harvestmen are able to regenerate the limbs and will remain active until the first hard freeze. While most succumb to the autumn chill, some overwinter in mulch piles, basements or other protected areas.

Sunday, September 2, 2007

Purple and Gold

In early September, the fields and prairies of the Midwest are adorned with patches of purple and gold. Ironweed, blazing star and late thistles yield the purple highlights, while tickseed sunflowers and a variety of goldenrods create a bright background of gold. These late summer colors seem especially brilliant as the grasses fade to brown and the greens of the trees and shrubs begin to mellow. And though the sun is dropping southward and the days are waning, the drier air makes the light more intense and the brilliant wildflowers shimmer against a deep blue sky.

These harbingers of fall coincide with other changes on the grasslands. Red-winged blackbirds, mourning doves and eastern bluebirds are flocking once again and the shallow prairie ponds attract an increasing diversity of shorebirds. Within a few weeks, blue-winged teal will appear on the lakes and migrant songbirds will fill the woodlands. God's season is almost here.

Saturday, September 1, 2007

Following Summer

Just as the first wave of autumn air has moved into Missouri, the nighthawks are drifting southward, bound for a winter in the Tropics. Dependent on flying insects for nourishment, these nocturnal hunters will stay well ahead of the freeze line and won't return to the Midwest until early May. Their smaller cousins, the chimney swifts, are more adventurous, hanging around until mid October and returning by mid April.

Of course, the nighthawks do not know that winter is coming and have never experienced the frosty nights of October. They live in a perpetual summer and their urge to migrate is not a response to the cool, dry air that has now invaded Missouri. Rather, the waning daylight triggers their instinct to drift toward the south and they often do so in large, scattered flocks. Watch for them at dusk on calm evenings, flapping and gliding above the city; their relatively large size, halting flight, white wing patches and sharp "peents" distinguish them from the smaller, fast moving swifts.