Sunday, November 23, 2014

The Great Appalachian Valley

The Great Appalachian Valley of North America, a series of topographic valleys separated by low divides, stretches for more than 1200 miles, from the Richelieu Valley of Quebec (which drains Lake Champlain) to the Coosa River Valley of northeastern Alabama.  While rivers have eroded (and continue to mold) the component valleys, geologic downwarping also shaped the terrain as adjacent mountains rose.

The eastern wall of the Valley is composed (from northeast to southwest) by the Green Mountains of Vermont, the Taconic Highlands of southern New England and the Blue Ridge Mountains, from south-central Pennsylvania through Virginia, North Carolina, Tennessee and northern Georgia.  The west wall consists of the Adirondacks and Catskills of New York and the easternmost ridge of the Ridge & Valley Province, from Pennsylvania to Alabama.  Some of America's most famous rivers course through sections of the Valley (including the Hudson, the Susquehanna, the Shenandoah and the Upper Tennessee) while others, such as the Mohawk, Potomac, Delaware and James Rivers, enter or cut across the Valley.  Cities within the Valley include Burlington, Albany, Harrisburg, Hagerstown, Winchester, Harrisonburg, Bristol and Maryville, among others.

Indeed, the Great Appalachian Valley is not a closed basin and its walls are not continuous.  Rather, rivers enter and leave the Valley through "water gaps" that formed as the mountains rose beneath the entrenched streams.  Nevertheless, the "Great Valley," with its rich soil, diverse ecosystems and scenic vistas, has long provided a natural highway through mountainous terrain for wildlife, Native Americas and modern travelers alike.

Saturday, November 22, 2014

Two Cities, Two Owls

Great horned owls are the nocturnal avian predators along the Colorado Front Range, feasting on prey as large as skunks, geese and raccoons.  Not often heard during the warmer months of the year, their gruff hoots begin to echo across our Littleton farm by mid November, continuing through their mid winter breeding season and trailing off by early spring.  Utilizing abandoned hawk or magpie nests (or drum nests placed by humans), these powerful raptors are perhaps best observed in late winter, when mom and her downy youngsters stare down from their roost in a cottonwood grove.

In Columbia, Missouri, our neighborhood is amidst a network of wooded stream valleys and barred owls are far more common than their larger cousins; delivered throughout the seasons, their mellow, questioning calls may be heard day or night.  Barred owls lack the "ear tufts" of great horned owls, have dark eyes and often tolerate close approach, peering down from a trailside tree as hikers pass below.  Their diet, consisting primarily of mice, voles and rabbits, may also include reptiles, amphibians and songbirds; tree cavities are generally used for nesting and, in my experience, mother and young are far less conspicuous than the families of great horned owls.

In either of my home towns, I relish the sight and sound of owls, a natural highlight of the fall and winter months.  Hardy yet mysterious, these efficient hunters rule the night, the hours when we humans are ill equipped to function; it is perhaps that sense of inadequacy that fuels our admiration for these nocturnal raptors.

Thursday, November 20, 2014

Snow Disaster in Buffalo

The poster child for lake-effect snow events struck South Buffalo, New York, this week, dropping up to six feet of snow.  According to local weather officials, this is the greatest one-day snowfall in at least 40 years; given the fact that the Great Lakes have existed for about 12,000 years, it's anyone's guess where this crippling storm falls on the spectrum of past lake-effect snow events.

Frigid air, moving west to east over the relatively warm waters of Lake Erie, produced the spectacular accumulation of snow.  Once the wind shifted from a more southerly direction, the skies cleared and the snow machine was shut down; unfortunately, that wind shift is expected to be brief and lake-effect snows are forecast to resume in the Buffalo area, perhaps dropping another two feet or more.

Lake-effect snow bands, like snow-guns used at ski areas, can produce dramatic snow accumulation in one linear region with little or no snowfall to either side of that band; though South Buffalo was buried under six feet of snow, the city's airport, to the north, received only six inches.  Those caught within the band may be trapped in their homes or vehicles and face the threat of falling limbs or collapsed roofs; worse yet, subsequent rainfall, which is expected in the region, is absorbed by the snow, increasing its weight before spawning destructive floods.

Wednesday, November 19, 2014

Pipeline to Oblivion

Political, corporate and public support for the Keystone Pipeline is a direct repudiation of efforts to reduce fossil fuel consumption across the globe.  Touting the economic and societal benefits of the project, supporters voice little concern for its environmental impacts, including our continued reliance on a product that threatens the welfare of our planet.

The tar sands of northeastern Alberta, Canada, lie within Cretaceous sediments of the Athabasca River Valley.  Extraction of their heavy crude has involved both open pit mining and in situ techniques (which require large volumes of water, diverted from the river).  Both forms of extraction threaten the regional environment, either via direct destruction of boreal bogs and forest or by pollution of the river and its tributaries.  Of course, transportation of the heavy crude in a pipeline that crosses the American Heartland raises the possibility of spills in rivers, prairies, wetlands or vital agricultural areas along the way.

But the primary threat of the Keystone Pipeline is its reinforcement of our dependence on fossil fuel.  A shift toward natural gas utilization and clean, renewable energy production have gained significant traction over the past decade, fueled by the threat of global warming, recurring incidents of pollution (such as the BP disaster in the Gulf of Mexico) and the political ramifications of the international oil market.  Support for the Keystone Pipeline demonstrates an unwillingness to address the ongoing, man-induced degradation of Planet Earth and our accelerating march toward oblivion.

Tuesday, November 18, 2014

A Tribute to Stephen Hawking

Yesterday, my wife and I saw The Theory of Everything, the story of Steven Hawking's rise from a socially awkward graduate student to an international celebrity and pioneering genius in the field of theoretical physics.  His accomplishments, of course, unfolded despite the ravages of ALS that eventually confined him to a wheelchair and necessitated the use of a computerized voice machine; though initially advised that he had two years to live, Steven Hawking continues to lend his intellect and insight at the age of seventy-two.

While some reviewers have criticized the movie for its simplified treatment of Hawking's theories on time, black holes and the origin of the Universe, I thoroughly enjoyed and highly recommend the film; it effectively blended the roles that love, intelligence and perseverance played in his development as a physicist and as a human being.  It also highlighted Hawking's view that mysticism has no place in science while relating his conviction that the search for truth in the Universe does not diminish the value and potential contribution of each human life.

Though few are blessed with Hawking's intellect, we can all insist on intellectual honesty as we face the challenges of our lives and the mysteries of our vast Universe.  Mysticism need not taint the purity of love nor derail our science-based search for truth.

Monday, November 17, 2014

Harlan's Hawk

Harlan's hawk is a large, dark-plumaged buteo that breeds across Alaska and Northwest Canada.  Once considered a distinct species, this powerful raptor is now classified as a subspecies of the red-tailed hawk, which ranges across most of North America.

Come autumn, Harlan's hawks head primarily for the Southern Plains, from the base of the Front Range to Arkansas and Texas, though individuals have been observed throughout much of the U.S., especially west of the Mississippi River; fortunately, one of these northern predators has been wintering on or near our Littleton, Colorado, farm over the past few years.  His bulky form is often observed on a phone pole or in a large tree, searching the fields and pastures for mice, voles or cottontails.  Oblivious of the frigid air and snow, he is an impressive representative of the vast northern wilderness that is his home.

Indeed, one of the benefits of birding is the opportunity to enjoy the seasonal presence of wild creatures that spend the majority of their lives in distant lands.  More importantly, we come to appreciate that Earth's varied ecosystems are interdependent and that the welfare of these avian travelers is directly related to the health of those widely spaced ecosystems, some of which are heavily impacted by human activity.

Sunday, November 16, 2014

Mount Pavlov Eruption

Mount Pavlov, 8560 feet, is a stratovolcano on the Alaskan Peninsula, some 600 miles southwest of Anchorage.  It formed within the last 10,000 years, on the northeast edge of the Emmons Lake Caldera (the remnants of an ancient volcanic explosion); like all of the Aleutian Volcanoes, it is the product of subduction, as the Pacific Plate dips beneath the North American Plate, causing its edge to melt and fuel volcanism.

The most active volcano in Alaska, Mount Pavlov has experienced numerous eruptions, most of which have been relatively benign due to both the volcano's structure and its remote location.  The current eruption began earlier this week with little fanfare; however, over the past 24 hours, Mt. Pavlov's ash plume has intensified, rising 30,000 feet above sea level and threatening air traffic in the region.

Such is the nature of "natural disasters" across the globe.  While the physical evolution of Planet Earth continues, just as it has for 4.6 billion years, we humans ignore (if not dismiss) that evidence until it directly threatens our personal welfare.  As a consequence, we construct cities within subduction zones and along major fault lines, convinced that we are the endpoint of God's master plan, not just another species, subject to the natural forces that mold this planet.

Saturday, November 15, 2014

A Wintry Waterfowl Count

For the first monthly waterfowl count of the winter season, wintry conditions enveloped South Platte Park in Littleton, Colorado.  Following a one day respite from this week's frigid weather, a second phase of the Polar Express is pushing across the State and light snow developed along the Front Range early this morning.

Needless to say, the cold air, blowing snow and steam-shrouded lakes made the counting difficult at times.  Nevertheless, our group encountered a large number and variety of species on the South Platte and its floodplain lakes; Canada geese, gadwalls, northern shovelers and American widgeon were most abundant, joined by mallards, lesser scaup, buffleheads, common goldeneyes, hooded mergansers, northern pintails and green-winged teal.  Other sightings included pied-billed grebes, a lone western grebe, a muskrat and a rough-legged hawk.

As the lakes freeze over during the winter months, some of the waterfowl will head further south but most will simply move to the the river channel, where the flowing water remains open.  Due to our recent Arctic outbreak, that relocation may be well ahead of schedule.

Thursday, November 13, 2014

A Frigid Morning at Red Rocks

Red Rocks Park, in the foothills west of Denver, is best known for its outdoor, rock-walled amphitheater, which, over the years, has hosted a wide variety of concerts and other forms of entertainment.  To birders and naturalists, the Park is also known as an excellent place to explore the flora and fauna of the Front Range shrub zone.

Today, my friend and I arrived at the snow-laden landscape of Red Rocks Park by mid morning; the air was calm but the temperature was 8 degrees F.  Since he is a wildlife photographer, we headed straight for the feeder area behind the Trading Post, well known as a magnet for resident birds, migrants, wintering species and rare vagrants.  Though recent reports indicated sightings of golden-crowned sparrows at the Park, we failed to observe them today; neither did we see rosy finches, which often invade Red Rocks after winter storms rake the mountains.  At the feeders, four races of dark-eyed juncos were the most numerous visitors, followed by black-capped chickadees, house finches, scrub jays, black-billed magpies, song sparrows and spotted towhees.  Throughout the remainder of the Park, birds were rather sparse, represented primarily by magpies and red-tailed hawks; despite expectations, no Townsend's solitaires were found.  Mule deer, on the other hand, were abundant, prancing through the snow or foraging on the yucca-studded meadows.

Wildlife observation in frigid weather is always a challenge but it gives one a better appreciation for the hardiness and adaptability of our wild neighbors.  Of course, handouts are welcomed by many species of wildlife and concentrate their activity for the benefit of human observers; then again, they concentrate victims for predators as well!


Wednesday, November 12, 2014

The Rosetta Mission & Climate Change

Today, ten years after its launch and at the end of a 4 billion mile journey, the Rosetta spacecraft successfully landed its Philae probe on a comet.  The latter was traveling at 85,000 miles per hour and the rendezvous occurred 311 million miles from Planet Earth.  Scientists hope to learn more about the birth of our solar system from data collected on the comet's surface.

This stunning achievement is the culmination of a project that began long before liftoff and, of course, owes its success to the knowledge that we humans have accumulated over more than five centuries.  Few would deny that this feat is just the latest in a long history of monumental scientific achievements, all of which have drawn from our understanding of the laws of nature.

Yet, many who applaud the success of the Rosetta mission remain unwilling to accept the scientific evidence of global warming.  Whether motivated by religion, politics or personal interests, they choose to ignore (if not ridicule) science when it threatens their belief system or their economic welfare.  While the new knowledge gained from the surface of a comet will help to clarify the nature of our planet's origin, opposition to the science of climate change will undermine efforts to understand its future.

Tuesday, November 11, 2014

Escape from the Frigid Upslope

Facing a cold, cloudy day with intermittent flurries (courtesy of this week's Polar Express), we and our guests escaped to the Western Slope of the Continental Divide.  Climbing through the frigid fog along Interstate 70, we left the upslope clouds just beyond Georgetown, Colorado, which sits at 8500 feet.  From there westward, we enjoyed sunny skies and relatively mild November conditions.

We ended up in Vail for lunch and an afternoon of hiking and birding; highlights of the latter included flocks of cedar waxwings and pine grosbeaks, in town to feast on the varied crops of berries.  We looked in vain for common dippers along Gore Creek but did encounter a ruby-crowned kinglet, seemingly a bit tardy for his journey to the south.

Following our pleasant afternoon west of the Divide, we returned to Metro Denver, re-entering the upslope fog at Georgetown and eventually crawling from the foothills and through the city, where late day snow and temperatures in the teens (F) created icy roads and snarled traffic.  Due to other plans, we won't be able to escape the Arctic blast for the next two days but it's nice to know that topographic relief is just an hour's drive away!

Monday, November 10, 2014

Watching Winter Arrive

This morning dawned clear, sunny and mild along the Colorado Front Range.  Knowing that a potent cold front was on its way, we introduced our visitors to several State Parks, hoping to complete our tour before the Arctic blast arrived.

A quick drive through Chatfield State Park was followed by a hike at Roxborough State Park; enjoying the wildlife and scenic rock formations at Roxborough, we could see a wall of clouds building to our north.  Though it was too warm to hike in a heavy sweatshirt or jacket, we knew that the warm sunshine (64 degrees F by mid morning) would soon give way to wintry conditions.

As the clouds pushed southward, gusty winds produced dust storms across Metro Denver and we headed for the hills, climbing through Deer Creek Canyon and then angling southwestward on U.S. 285.  We were headed for Staunton State Park, on the south side of the Mt. Evans massif and west of a high ridge that cuts across Conifer, Colorado.  There, protected from high winds and the rapidly developing upslope, we enjoyed a loop hike through the montane forest, encountering red crossbills, Abert's squirrels and mule deer, among other common wildlife species.  By the time we returned to our Littleton farm, fog and snow showers enveloped the urban corridor and the temperature had fallen 40 degrees in less than 2 hours (to 24 degrees F).

Saturday, November 8, 2014

Return of the Bark Birds

A pair of brown creepers returned to our central Missouri neighborhood this week and will be observed on occasion throughout the colder months.  After nesting in the Northwoods of Canada, southern Alaska and the Great Lakes region and southward through the Appalachians and Western mountains, these small, slender birds leave their coniferous homeland to winter in mixed woods throughout much of the U.S.

Commonly encountered in parks and suburban areas, brown creepers favor areas with large trees where they circle up the trunk, searching for hibernating insects and spiders.  Nearing the top of the trunk or one of its major branches, they fly to the base of another tree and begin to climb and search once again, picking through the bark with their curved bill.  During their winter visit, creepers may also turn up at suet feeders and frequently join mixed flocks of chickadees, titmice and downy woodpeckers in the barren woods.

Resembling pieces of bark themselves, brown creepers are monogamous during the breeding season and often suspend their nest behind a piece of loose bark; both parents take part in raising the young.  Come autumn, the family members go their separate ways, some remaining in their summer range while others travel hundreds of miles across the lowlands of North America.  Known to winter in flocks on occasion, creepers are (in my experience) most often seen alone or in pairs.

Friday, November 7, 2014

Water: Sculptor of the Earth

While plate tectonics rearranges the Continents, lifts mountain ranges and ignites volcanism, water sculpts the surface of Planet Earth.  Falling as rain, snow or ice pellets and lashing the coastlines as waves, this vital substance erodes and shapes our landscapes.

Whether moving as liquid water in rivers and streams or as solid ice in glaciers, water sculpts the mountains, plateaus and mesas of our planet, carving cirques, canyons and valleys and then spreading that debris across the lowlands or delivering it to lakes and oceans.  Along the margins of the Continents, wind-driven waves mold the shorelines, producing cliffs, sea stacks and barrier islands.

Of course, vegetation modifies this erosion in many regions, stabilizing soil and dunes, slowing and filtering the flow of streams and absorbing excess precipitation.  Unfortunately, we humans have a history of destroying that protection by draining wetlands, clearing forests and plowing prairies, augmenting the risk of destructive floods.

Thursday, November 6, 2014

Africa's Aquatic Dinosaur

Last evening, NOVA, on PBS, focused on the discovery and evaluation of Spinosaurus fossils, the largest carnivorous dinosaur yet unearthed and the only one known to have been semi-aquatic.  Larger than Tyrannosaurus rex, Spinosaurus lived in the Saharan Desert region of North Africa, some 95 million years ago.  Its fossils have been found in a layer of late Cretaceous sandstone which also contains the fossils of numerous marine creatures, indicating that a shallow sea covered much of the region during that period.

Characterized by a long, crocodilian snout, relatively large forelimbs and a large, boney fin on its back, Spinosaurus would have been too top-heavy to walk upright like T. rex; indeed, paleontologists have concluded that it was primarily aquatic (scouring the shallows for large fish, sharks and other marine life) and only came ashore to sleep, nest or perhaps to feast on small terrestrial vertebrates.  Its conical teeth and flat feet (both seen in crocodilians) favor this hypothesis.

One of the most interesting aspects of the Spinosaurus story is that fossils of this giant predator were first discovered in Egypt by Ernst Stromer, German paleontologist, but were unfortunately destroyed by a bombing raid during WWII; almost 100 years later, other fossils were dug up in Morocco and sold to a museum in Milan, Italy, setting the stage for the high-tech investigation reported on NOVA.  A full skeleton of Spinosaurus has yet to be found but many surely lie beneath the vast sands of the Saharan Desert.

Wednesday, November 5, 2014

The Anti-Science Coalition

Back when foresighted individuals such as Galileo and Copernicus led humanity toward scientific enlightenment, the Church condemned their theories and attempted to quash their influence.  Over time, as science fueled the industrial and technologic revolutions, religious organizations were forced to acknowledge that the theories of those intellectual pioneers had been valid; nevertheless, where scientific evidence directly undermines the basic doctrines of religion (e.g. evolution), the Church, in its varied forms, continues to reject the message.

Over the past few decades, political forces have joined the anti-science coalition, specifically in the area of global warming.  Protecting industries that fund their livelihood (i.e. the oil, gas and coal companies), conservative politicians ridicule the scientific evidence put forth by climatologists.  In doing so, they further diminish the value of science in the collective mind of an uneducated public.

Since the days of Galileo and Copernicus, science has strived to uncover truths pertaining to the laws of nature and the evolution of our Universe.  When powerful religious and political leaders undermine that effort with mysticism and rhetoric, the welfare of our planet (and, of course, of humanity itself) is placed at risk.  Truth cannot prevail in a climate of fear, deception and ignorance.

Monday, November 3, 2014

Anticipation on the Eastern Plain

Driving to Cincinnati today, I crossed the eastern portion of North America's Glaciated Plain, which stretches from western Illinois to central Ohio.  It is a relatively flat landscape of crop fields and hay pastures (once a tallgrass prairie), laced with streamside woodlands.

On this calm, mild November day, the region and its wildlife seemed to be laying low, awaiting the turmoil of the coming season.  The spectacular October colors were fading toward brown and the trees had undergone a variable degree of defoliation.  Red-tailed hawks perched in trees along the highway or lazily soared above the drying fields while flocks of turkey vultures tilted in the gentle southerly breeze.  Migrant waterfowl speckled the numerous farm ponds and groups of crows strutted through the corn stubble, picking at waste grain and sluggish grasshoppers.

As a traveler through that rural landscape, I sensed anticipation in its wild residents.  They may enjoy another week or two of mild conditions but winter is on the doorstep, ready to coat the trees and fields with ice or send frigid blasts of snow across the flat terrain.  Indeed, another jolt of cold air is expected by mid week and memories of last year's severe winter linger in the minds of Midwesterners; fortunately, the wild residents are not subject to such rumination and the culling season actually favors the raptors and scavengers that patrol this unforgiving landscape.

Sunday, November 2, 2014

Migratory Woodpeckers

Mention migrant birds and most of us think of waterfowl, shorebirds, seabirds and a wide variety of songbirds; few would think to include woodpeckers in that mix.  Indeed, most woodpeckers are permanent residents of their home territory, perhaps descending from higher elevations or moving among seasonal habitats but not leaving for more southern climes as winter approaches.

The primary exceptions are the sapsuckers, which prefer to feast on insects and sap.  Yellow-bellied sapsuckers breed across Canada, the Great Lakes region and New England but winter in the Southeastern States and Mexico.  Red-naped and Williamson's sapsuckers summer in the Rockies and Intermountain West but winter from the southern Colorado Plateau and Desert Southwest into Mexico; some Williamson's sapsuckers are permanent residents of the Sierra Nevada range.  Finally, red-breasted sapsuckers breed in British Columbia, southeastern Alaska, the Pacific Northwest States and the Sierra Nevada; most leave more northern latitudes and higher elevations during the colder months.

Lewis' woodpeckers, often seen in flocks, are summer residents of the Rockies, Pacific Northwest and Great Basin, permanent residents of California, the Colorado Plateau and Southern Rockies foothills and winter residents of the Desert Southwest.  Even some of our more common and widespread woodpeckers demonstrate a limited degree of migration; northern flickers leave their Canadian and Alaskan breeding grounds during winter, red-bellied woodpeckers move south from the Great Lakes and southern New England and red-headed woodpeckers abandon the Great Plains and the northern tier of the U.S.    

Saturday, November 1, 2014

Football Weather

As we move deeper into autumn, the term "football weather" is frequently heard.  In many cases, it is used to define unpleasant conditions that devoted fans must endure, including torrential rains in the Deep South, frigid temperatures across the Northern Plains or blowing snow in the Mountain States.  More often, however, it refers to crisp, breezy days, the air faintly scented with barbecue fumes or wood smoke.

Today, it is the latter that envelops Columbia, Missouri, where the Tigers host the Kentucky Wildcats.  Not heading to the game, I'll catch parts of it and other contests on the TV but find it impossible to remain glued to the couch on such a beautiful autumn day, our first chilly afternoon of the season.  After all, there are leaves to rake, feeders to fill and fresh air to inhale.

Like many half-hearted fans, I enjoy football primarily due to the season in which its games take place. In the American Heartland, football weather is synonymous with the glorious days of autumn, with their invigorating air, colorful foliage, active wildlife and spectacular flocks of migrants.  Good for contests on the gridiron, the conditions are even better for outdoor exploration.

Friday, October 31, 2014

Conservatives are Scary Enough

Driving across Kansas yesterday, I was repeatedly schooled on the Conservative message that, they hope, will give them control of the Senate after next week's election.  In a nutshell: they will oppose every program or policy that the Obama Administration has ever enacted, proposed or considered.

Voicing a disdain for the Federal Government (with the obvious exception of the Department of Defense), Conservative Republicans still promise to repeal Obamacare and to eliminate other frivolous components of the Federal Bureaucracy (such as the Environmental Protection Agency and the Department of Education); no word on cutting the Farm Bill or the Agriculture budget.  While they abhor governmental regulations that "threaten" corporate profits and gun ownership, they are quick to promise legal action that will block, abolish or diminish the rights of women, gays and immigrants.  In effect, they hope to impose their Conservative "values" on the rest of American society.

Tonight, as witches, goblins and pirates invade our front porch, I will feign fright in the spirit of Halloween.  In reality, the words and policies of Conservative politicians are far more unsettling.

Wednesday, October 29, 2014

First Winter Ducks

Yesterday morning, after the potent Colorado sun had warmed the cold night air, I headed down to South Platte Park to see if the rather sluggish waterfowl migration had yet to begin.  The answer awaited on Eaglewatch Lake, where a flock of buffleheads had gathered on the calm, cool waters.  Based on my personal observations, these were the first winter ducks to arrive in the valley.

As expected, they were joined by a variety of summer and permanent residents, including double-crested cormorants, gadwalls, northern shovelers, mallards, pied-billed grebes and common and hooded mergansers.  Noisy flocks of Canada geese, still awaiting the arrival of their northern cousins, passed overhead and a pair of belted kingfishers chattered along the shoreline.  Other sightings included red-tailed hawks, ring-billed gulls, magpies and northern flickers.

No doubt, the buffleheads rode the northerly winds behind our recent cold front and other waterfowl will do the same in the coming weeks.  Depending on conditions up north, migrant geese generally appear along the Front Range in early November and most winter ducks have arrived by the middle of the month.  Contrary to what non-birders might expect, the number and variety of ducks in the South Platte Valley is greatest during the colder months of the year.