Thursday, September 3, 2015

Armadillos in Central Missouri

In my post The Armadillo Army, in 2012, I reported that nine-banded armadillos, native to Central America, had spread into southern Missouri and southern Kansas and were expanding northward across the Coastal Plain toward the mid Atlantic region.  While isolated sightings in mid Missouri have been reported since 2010, the armadillo population has increased significantly in recent years.

Over the past month, I have seen two dead armadillos along Interstate 70 (east and west of Columbia) and four others on roads within the city.  Mid summer is breeding season for nine-banded armadillos and this fact, combined with their nocturnal wanderings, may explain the recent spike in roadkills.

Not equipped to survive long periods of cold weather, armadillos along the I-70 corridor are surely pushing the northern limit of their range; indeed, we have had severe winter weather in recent years.  On the other hand, their continued northward expansion may be yet more evidence of our warming climate.  Perhaps another century of warming will take them into southern Canada!

Wednesday, September 2, 2015

Migration Season at Eagle Bluffs

Though summer heat still envelops Central Missouri, there are signs of a seasonal shift at Eagle Bluffs Conservation Area.  On my visit to the floodplain yesterday, summer songbirds were still evident in the woodlands and the greenery, though fading, was not yet tinged by the hues of autumn.  Across the northern half of the preserve, little change was evident and wildlife was rather sparse; turkey vultures soared above the grasslands, a few great blue herons stalked the shallows and a lone bald eagle perched atop a wood duck box.

However, near the southern tip of the refuge, meandering pools and channels, flanked by mudflats, had attracted large flocks of great egrets and migrant shorebirds, soon to depart for southern climes; green herons fished along the shorelines and a small group of double-crested cormorants lounged on a sandbar.  Joining these migrants and summer residents were numerous killdeer, a large number of great blue herons, Canada geese, a few wood duck families, small flocks of mallards and a pair of belted kingfishers.

This seasonal shift will intensify in the coming weeks as flocks of blue-winged teal arrive on the floodplain, joined by an increasing number of cormorants and American white pelicans.  Coot, duck and grebe migrations will build through October and, as autumn chill deepens in November, the spectacle of migrant snow geese will grace the Missouri Valley.


Monday, August 31, 2015

Morning Moon

As I walked through campus this morning, a full moon gleamed above the western horizon.  Its cream-colored disc, reflecting the glow of sunrise, was the only defect in a pale blue sky.

Unchanged for billions of years, our lone satellite lit midnight beaches as the first terrestrial creatures scrambled ashore and glowed behind smoky darkness after a massive asteroid ended the reign of dinosaurs.  So too has it witnessed the evolution of our species, passively illuminating both the achievements and atrocities that have marked our history.

We humans, focused on the routine of our daily lives, associate the moon with darkness, taking little notice when it traverses a sunlit sky.  But its steady presence is vital to our existence, stabilizing the Earth's axis and dousing the shores with nourishing tides.  Inspiring song and poetry since the dawn of man, the moon's tranquility belies its violent birth and bleak landscape but stirs the soul of all who gaze on its celestial beauty.

Friday, August 28, 2015

The Freedom of Naturalism

Naturalists, myself included, believe that humans are part of nature, no more important than other species and, compared to some like fungi and photosynthetic plants, far less vital to the health of natural ecosystems.

Unfortunately, our large brains have convinced most humans that we are superior to other life forms, created in the image of a deity and immune to the predator-prey relationships that govern the lives of plants and other animals; indeed, many religious individuals are loath to classify humans as animals and strongly oppose the "theory" that we evolved from other primates.  Our numerous similarities to other mammals, including anatomic, biochemical and behavioral traits, are overshadowed by the intelligence and imagination that our large brains afford.

Of course, those who believe that humans are unique among life forms, endowed with spirituality and intimately tied to their divine creator, must live with the guilt and fear that stem from that belief.  Naturalists, accepting the fact that morality, unrelated to religious doctrine, is ingrained through evolution to enhance social cooperation and survival, are free to live without the threats imposed by a vindictive and manipulative deity.  We cherish our time on Earth, knowing that death will come but soaking in the heavenly rewards of life while we can.

Thursday, August 27, 2015

Assisting Nature

As a volunteer at a local nature preserve, I generally participate in songbird or waterfowl counts; on occasion, I have assisted with garden maintenance, trail work or habitat restoration.  Yesterday, I agreed to take part in the collection of wildflower seeds that will be used in improve floral diversity in other areas of the preserve.

While I have no major objection to such projects, I am inclined to let nature control and mold her ecosystems.  As self-appointed stewards of the natural environment, we should focus on protecting wild areas, eliminating pollution and minimizing the impact of human "development" and activity.  The more we interfere with natural ecosystems the more we are likely to upset their balance and threaten their welfare.

Even the reintroduction of native plants and animals can have an adverse impact unless all other components of that ecosystem are in place and adequately represented.  For example, the release of native prey species (e.g. elk, moose) without reintroducing their natural predators (e.g. wolves) can lead to the destruction of habitat (due to overgrazing, tree damage, etc.).  The less we play this management game the better; in the end, if we protect natural ecosystems and otherwise leave them alone, the native inhabitants (plant and animal) will return.  

Tuesday, August 25, 2015

Headwaters of the Colorado

About 28 miles west of Metro Denver, U.S. 40 cuts northward from Interstate 70, climbing to Berthoud Pass on the Continental Divide.  North of that pass, the highway descends into the valley of the Fraser River, a tributary of the Upper Colorado; the rivers merge in Granby, where the Colorado River flows in from the east and continues on to the west.

From Granby, eastbound U.S. 34 leads eastward and then northward through the Upper Colorado Valley, passing a scenic trio of lakes (Lake Granby, Shadow Mountain Lake and Grand Lake), all backed by the high peaks of the Front Range; the Colorado actually flows through Shadow Mountain Lake and Lake Granby.  North of Grand Lake, U.S. 34 enters Rocky Mountain National Park and gradually climbs through the Kawuneeche Valley, the path of the Colorado's uppermost segment; tributaries from the Front Range (to the east) and the Never Summer Range (to the west) feed the main channel.  The Colorado River Trail, which leads to the river's headwaters on the Continental Divide, is accessed from a trailhead lot off Trail Ridge Road (U.S. 34), just before the latter begins its climb to the alpine tundra.

Visiting the Kawuneeche Valley today, I hiked part of the Colorado River Trail and took a few side trails that lead down to the stream or into the valley meadows.  By late summer, the Upper Colorado is but a small creek and it's difficult to associate this gentle, meandering stream with the river's raging torrent far to the southwest.  Of course, many large tributaries merge with the Colorado along its course and the river carved its spectacular canyons primarily during the Pleistocene, a time when a cool, wet climate enveloped North America and when mountain glaciers filled the Kawuneeche Valley.

Sunday, August 23, 2015

Denver from Above

My son, intent on getting his pilot's license, invited me along for his first lesson today.  Taking off from Centennial Airport, we curved to the southeast and then followed Cherry Creek NNW to downtown Denver.  From there we headed west to Golden, crossing Sloan's Lake and the Clear Creek Valley en route.

Flying southward above the edge of the foothills, we enjoyed fine views of South Table Mountain, Lookout Mountain, Red Rocks Park, Green Mountain and Bear Creek Reservoir.  At my urging, we angled ESE to pass above our Littleton farm; the lakes of South Platte Park shimmered to the south, backed by the large swath of Chatfield Reservoir and its State Park.  Continuing eastward above C-470, we made a final loop to the south before landing at Centennial.

Long a fan of air travel, which provides a unique perspective of Earth's varied landscapes, it is especially interesting in one's home territory, where the geography of our daily life unfolds below.  Though partially diminished by the smoke of distant wildfires, today's aerial survey was a fabulous experience.  My thanks to Zach for the invitation!

Saturday, August 22, 2015

More Lessers

Lesser goldfinches are summer residents along the Colorado Front Range, usually arriving in late April and departing by early October; those that summer in Colorado winter in the Desert Southwest, South Texas or Central America.

While they favor foothill canyons and shrublands, lesser goldfinches often visit our Littleton farm during the warmer months and have nested here on occasion.  However, it is in late summer that they are most numerous, usually appearing in large flocks and hanging around for several weeks.  Their breeding season has now ended and the small, vocal finches are feasting on the seeds of sunflowers, thistle and other grassland wildflowers before their fall migration.

The smallest finches in North America, lesser goldfinches are represented by several subspecies.  Males along the Front Range have black crowns and backs while those further west have black foreheads and green backs.  In all regions, it is their distinctive, high-pitched call (often delivered in flight) that usually brings them to our attention.


Friday, August 21, 2015

Wildfire Haze

A wet spring and early summer has, so far this year, protected Colorado from wildfires.  Nevertheless, some 95 wildfires are burning across the drought-plagued West (especially in the Pacific Northwest) and the smoke from those fires has invaded the Front Range of Colorado.

Reminiscent of the "brown cloud" inversions of past decades, the wildfire haze is obscuring visibility across the urban corridor, triggering respiratory symptoms in susceptible individuals, inducing eye irritation and almost eliminating views of the mountains to our west.  Light winds and overlying high pressure are limiting diffusion of the smoke and exacerbating the air pollution.

While we humans make efforts to improve air quality, we remain at the mercy of natural events, such as volcanic eruptions and wildfires, that inject particulates into the atmosphere.  In many cases, our only recourse is to remain indoors or, if medically indicated, wear protective masks until a weather front sweeps the polluted air out of our region.  In the meantime, we can enjoy spectacular sunrises and sunsets, colored by the smoky haze.

Thursday, August 20, 2015

New Colorado Wind Farms

Returning to Colorado after a one month absence, I was both surprised and delighted to encounter a new wind farm north of Interstate 70, between Burlington, Colorado and the Kansas border.  Named the Carousel Wind Farm, this complex is being built and operated by NextEra Energy; it will contain 88 wind turbines and produce 150 MW of clean energy.

Were it not for a weather-induced detour (see Detoured by Storms), I would not have discovered the Golden West Wind Farm on the southern flank of the Palmer Divide, east of Colorado Springs.  Also built and operated by NextEra, this facility will use 145 turbines to yield 250 MW of energy production.

Despite the continued expansion of wind and solar energy production across the country, some Conservatives oppose this transition and hope to eliminate Federal tax credits that support clean energy programs.  After all, these programs compete with the oil, gas and coal industries, long backed by conservative politicians, and derive federal and public support from their role in addressing global warming, a great conspiracy in the eyes of right-wing Republicans.  Of course, in objecting to Federal support for clean energy systems, these same Conservatives fail to acknowledge the massive amount of tax credits extended to fossil fuel industries over the past Century.

Wednesday, August 19, 2015

Jackson on the Rocks

Last evening, my daughter Sarah treated me to a Jackson Browne concert at Red Rocks Park, in the foothills west of Denver.  The Park's famous amphitheater, set between towering slabs of Pennsylvanian sandstone (300 million years old), offers both excellent acoustics and a spectacular view of Metro Denver.

Mother Nature was not overly cooperative early in the evening, as a chilly breeze and light drizzle moved in from the west.  But the April-like weather soon drifted off to the east and the lights of the city were temporarily obscured by the spreading mist; later still, thunderstorms developed above the distant Eastern Plains, adding nature's light show to the one on stage.

Meanwhile, back at the amphitheater,  Jackson and his group served up a mix of old and new songs; fortunately, two of my favorites (These Days and Fountain of Sorrow) were included.  Browne's poetic lyrics, laced with liberal philosophy and political activism, have long been a source of inspiration for myself and many fellow "Boomers."  As one might expect, the scent of pot drifted across the amphitheater at times, adding to the nostalgic effects of Jackson's songs.  Great music in a beautiful natural setting is hard to beat!  My sincere thanks to Sarah for a wonderful evening.

Tuesday, August 18, 2015

Detoured by Storms

Returning to Colorado yesterday, I headed west on Interstate 70, a ribbon of concrete that essentially divides the Northern and Southern Plains of the U.S.  As is typical during the summer months, there was little to attract my interest on the Plains; raptors were limited to a few hawks and vultures while mammals were represented solely by livestock and roadkill, the latter including deer, coyotes, badgers and raccoons.  Migrant shorebirds were observed in some of the shallow pools but were impossible to identify at 75 mph.

Nearing Limon, Colorado, my boredom suddenly gave way to concern as dark clouds stretched across the western horizon; intense lightning flashed from several areas and the radio broadcast was interrupted by warnings of severe thunderstorms with large hail and a few funnel clouds.  Taking refuge at a truck stop, I waited for the storms to pass; high winds, torrential rain and light hail pummeled the city.  Unfortunately, two trucks were flipped over by the winds, closing westbound I-70 north of town.

Once skies began to clear, I thus headed west on U.S. 24, traveling across the southern flank of the Palmer Divide toward Colorado Springs.  The massive storms now loomed to the southeast, adorned with a rainbow, and the scenic grasslands of the Divide captured the glow of a setting sun; upslope moisture still obscured the Front Range.  As I closed in on Colorado Springs, the Pike's Peak massif emerged from the haze, the Rampart Range stretched off to its north and the Wet Mountains and Spanish Peaks appeared to the southwest.  Northbound I-25 to Castle Rock and U.S. 85 to Littleton would complete the detour to our farm.

Friday, August 14, 2015

The Yellowstone River

The Yellowstone River, the largest tributary of the Upper Missouri, rises on the western flank of the Absaroka Range, southeast of Yellowstone National Park in northwest Wyoming.  Dropping to the Yellowstone Plateau, the river feeds and then drains Yellowstone Lake; north of the lake, the river cascades through its Upper and Lower Falls and passes through scenic canyons before continuing northward into Montana through Paradise Valley.

Leaving the Rockies at Livingston, the Yellowstone flows ENE across the High Plains of Montana, eventually merging with the Missouri River in western North Dakota, just east of the Montana border.  Along the way, major tributaries arrive from Wyoming, draining the east flank of the Absaroka and Wind River Ranges and both sides of the Bighorn Mountains; west to east, these are the Clarks Fork, Bighorn (see The Two-Basin River), Tongue and Powder Rivers (see Powder River Basin).

Just over 700 miles long (including its headwater forks), the Yellowstone is one of the most scenic rivers in the U.S., crossing and draining a spectacular mix of Western landscapes, home to a fabulous diversity of wildlife; among the latter are bison, elk, wolves, grizzlies, mountain lions, lynx, bighorn sheep, mule deer, pronghorn, river otters, prairie dogs, trumpeter swans, sandhill cranes and a host of western raptors and songbirds.

Thursday, August 13, 2015

Rose Mallow

More than 300 species of wild hibiscus are found across the globe.  While most of these colonize tropical and subtropical regions of our planet, a fair number are members of Temperate ecosystems.  Indeed, six species are found in wetlands of the eastern and central U.S.; among these, rose mallow is the most common and widespread.

Favoring rich, moist soil, rose mallow can be found along meandering streams, in floodplain wetlands or in freshwater marshes.  This perennial, deciduous shrub, like other species of hibiscus, is best known for its large, showy flowers, which, depending on latitude, bloom from late spring to early autumn; they currently adorn wetlands across Missouri and are especially abundant on the Missouri River floodplain. The flowers of rose mallow are generally white or pink with red or purple centers and bright yellow stamens.  Bees, butterflies and hummingbirds pollinate the flowers which, like daylilies, open for only a day.  Seed pods mature and dry out on the plant, eventually releasing seeds that are eaten by waterfowl, quail and a host of songbirds.

Humans have long been enamored with wild hibiscus, using the brightly colored flowers for decoration or to make tea; the latter is claimed to have a range of therapeutic benefits.  For most of us, however, the benefits of this plant derive from its natural beauty and its role in the health of wetland ecosystems.

Wednesday, August 12, 2015

September Preview

Yesterday was a gem of a day in central Missouri.  A cold front passed through our region during the early morning hours and, as I walked through campus just after dawn, a soft north breeze had pushed the hot, hazy summer off to the south.

Birdsong was noticeably more vibrant while the cicada chorus, not fueled by tropical air, was less intense.  Black walnuts are beginning to litter the lawns, the purple berries of pokeweed adorn their plastic pink stems and goldenrod has made its appearance at our local nature preserve.  One can almost hear the marching band and smell the tailgate grills.

While the pleasant September preview persists today, it won't last long.  Thick, humid air will soon return to the Heartland and oppressive heat will once again sap our energy.  But, almost two months after the summer solstice, the tide has turned.  Glorious autumn is just around the bend.

Tuesday, August 11, 2015

Disaster on the Animas River

The Animas River rises in the San Juan Mountains of southwest Colorado; flowing southward through Silverton and Durango, it merges with the San Juan River, a major tributary of the Colorado, in Farmington, New Mexico.  This past week, the Environmental Protection Agency, attempting to clean up debris at the Gold King Mine, accidentally released 3 million gallons of toxic, mustard-colored sludge into Cement Creek, a tributary of the Animas River.

Laced with heavy metals, including lead, arsenic and copper, the mine debris has now reached Utah (via the San Juan River) and will soon enter Lake Powell; meanwhile, the waters of the Animas have begun to clear though sludge has settled on the river's bottom.  Preliminary studies have shown no negative impact on fish and regional wildlife but the longterm effects of this accidental spill (which continues at a lower rate) are far from certain.

No doubt, toxic sludge has been seeping from Colorado's abandoned gold and silver mines since the 19th Century; similar pollution impacts streams throughout North America and across the globe.  While major spills such as this event and the recent coal ash disaster in West Virginia bring mining pollution to the attention of the general public, the slow, steady release of toxic chemicals from old mines is generally ignored.  Despite the accident at the Gold King Mine, the funding of mine cleanup programs must continue; of course, strict pollution control measures at active mines are the most effective way of preventing future disasters.

Monday, August 10, 2015

Dead Stick Walking

Yesterday afternoon, my wife spotted a walking stick on the ceiling of our back porch, a special treat for our two grandsons.  Not always so easy to find (due to their excellent camouflage) stick insects are primarily nocturnal and are best observed at dawn or dusk.

Found across the globe, especially in tropical regions, stick insects are represented by more than 3000 species; some exceed one foot in length (almost two feet with legs extended), among the longest insects on Earth.  Females are always significantly larger than the males and are far more common; indeed, in many species, female walking sticks are capable of parthenogenesis, producing identical female offspring without mating.  When mating does occur,  physical coupling may persist for days or even weeks.  Eggs are most often laid in loose soil or leaf litter and temperate zone species generally overwinter in that form.  Herbivorous, stick insects may cause extensive defoliation of trees and shrubs in some regions, a seemingly strange achievement for such a sluggish appearing insect.

Natural enemies of the walking stick include bullfrogs, snakes, lizards, toads, birds and bats.  They may also fall victim to human insect collectors who place these fascinating insects in terrariums.

Sunday, August 9, 2015

Southern Heat Dome

For the past few days (and perhaps quite a few more), a dome of high pressure has settled over the Southern Plains and lower Mississippi Valley.  Beneath that atmospheric dome, air is sinking and heating up, producing afternoon highs near or above 100 degrees F; since sinking air retards cloud formation, intense sunshine magnifies the discomfort.

Along the outer rim of the dome, cooler air is sliding beneath and lifting the hot air, igniting thunderstorms.  In concert, clockwise winds at the edge of the dome direct these storms in a broad arc; yesterday, these "riders" were moving from northeastern New Mexico and eastern Colorado across the Central Plains and then southeastward through the Tennessee Valley and down to the Gulf Coast.

While not always as widespread and intense, high pressure domes are common over the Southern Plains in August and play a major role in the development of the Southwestern Monsoon.  As Gulf moisture is drawn westward across Mexico, following the southern edge of the dome, it joins a moisture plume from the Sea of Cortez; the combined humid air masses flow northward along the western rim of the high pressure dome, feeding thunderstorms across the Desert Southwest and into Colorado (see also The Dome of August).

Saturday, August 8, 2015

Skink in a Basket

Moving a basket of seashells yesterday morning, I was startled when a five-lined skink scurried out and disappeared beneath the deck.  Its bright blue tail indicated that it was a juvenile, likely scouring the basket for insects.

Like other lizards, skinks may be observed basking on rocks, decks or bridges but are more often seen when they are startled by hikers or gardeners and race away for cover.  After all, much of their time is spent stalking prey (insects, earthworms and other invertebrates) amidst dense vegetation, their skin color (blue tail excepted) blending with the foliage.  On the other hand, opportunism may draw them to houses or outbuildings where various prey species (e.g. moths and beetles) often congregate.

Those of us who hope to observe such reclusive creatures must know their preferred habitat but must also count on a bit of luck.  Our encounter is often fleeting and identification may be difficult....unless, of course, it has a bright blue tail!

Friday, August 7, 2015

Killer in the Compost Bin

Dropping off last night's veggie scraps at our compost bin, I caught sight of a large centipede that scurried across the slatted wall as I opened the lid.  These carnivorous arthropods date back to the Silurian Period, some 440 million years ago, when they were among the first animals to colonize the land.

Today, more than 3000 species have been documented across the globe, inhabiting a wide range of ecosystems, from rocky seashores to deserts, from caves to alpine landscapes and from tropical rainforests to Arctic wetlands.  The varied species range in size from less than a quarter inch to a foot or more in length; the largest is the giant centipede of the Amazon basin, which is known to consume a variety of amphibians, lizards, songbirds and mice.  Most species feed on earthworms and other small invertebrates, using their foreleg pincers to grab prey and inject venom.

Despite their name, centipedes may have 30 to several hundred legs.  Since they do not have a waxy cuticle to prevent dehydration, centipedes must spend most of their time in dark, moist environments and are primarily active at night.  Of course, a shady, humid compost bin, filled with rotting vegetation, beetles and earthworms, offers an ideal hunting grounds for these fast-moving carnivores.

Thursday, August 6, 2015

A Local Expedition

After reading and writing about the journey of Lewis & Clark over the past few days, I decided to conduct an expedition of my own along the Missouri River.  So, this morning, I headed south from Columbia, dipping across Gans Creek at Rockbridge State Park, crossing wooded hills and rolling farmlands to its south and then dropping into the broad valley of Bonne Femme Creek.  Nearing the mouth of the latter stream, I parked my pickup and took a walk along the Katy Trail, a Missouri State Park that parallels the Missouri River for much of its course in the State.

Crossing the Bonne Femme bridge, I stopped to look for mink or otter along the creek's muddy banks; no success in that regard but I did spot a green heron hunting in the flotsam and a flock of red-headed woodpeckers in dead trees along the stream.  Woodlands along the trail were full of summer songbirds, including yellow warblers, yellow-breasted chats and blue-gray gnatcatchers.  Returning to my pickup, I drove out to the banks of the Missouri, just in time to see two bald eagles alight in the cottonwoods that line the river; red-tailed hawks, eastern kingbirds, great crested flycatchers and Baltimore orioles were also observed in those trees.  Cropfields and the brushy floodplain borders attracted a mix of sparrows, dickcissels, American goldfinches and indigo buntings while transient pools drew leopard frogs, snapping turtles, killdeer, spotted sandpipers, great blue herons and small flocks of migrant shorebirds.  Swallows (tree, barn and cliff) gathered on powerlines or strafed the fields and river, preparing for their journey to South America.

Gazing upriver, I realized that the landscape still looks very much like it did to Lewis & Clark in 1804; as if to strengthen that impression, a canoeist paddled down the river, his craft loaded with fishing and camping gear.  Though I did not encounter massive herds of bison, grizzlies or packs of wolves on my brief expedition, I did see at least forty species of birds on this bright summer morning, creatures that were all but ignored in the Journals of Lewis & Clark (at least in the edited version).  Sadly, most modern Americans are oblivious of this avian diversity as well.