Wednesday, October 31, 2018

Winter Tries Again

Just over two weeks ago, the first snowstorm and the first hard freeze of the season descended on the Colorado Front Range, putting an end to autumn for 48 hours.  Though many of the colorful leaves were taken down by the wind and snow, the temperature rapidly rebounded, the snow melted and we have enjoyed summer-like warmth ever since.  Of course, the longer nights produce chilly mornings but afternoon highs have been in the mid 60s to mid 70s (F).

Yesterday, another cold front pushed southward across Colorado, bringing a raw day with intermittent showers.  Overnight, that rain changed to snow and it continues this morning, with minimal accumulation; by this afternoon, the sun will return and the snow will disappear.  Mild conditions are expected for the next week, though temperatures will be more autumn-like.

Once again, winter will retreat northward but it will continue making incursions into the Heartland.  While its grip will likely solidify across the Midwest and Northeast by December, those of us along the Front Range will enjoy mild (if not warm) interludes, thanks to the intense sunshine, dry air and downsloping "chinook" winds.

Tuesday, October 30, 2018

Table Mountain, South Africa

Watching a film set in Cape Town, South Africa, today, I wondered about the geology of Table Mountain, which looms above the city.  As is often the case, the natural history of that famous massif is complex.

About 500 million years ago, during the Cambrian Period, a rift valley developed in the southern portion of a continental plate that included today's Continents of South America, Antarctica and Africa.  Initially flooded by a shallow sea, the rift accumulated sediments over the next 100 million years.  Throughout the late Paleozoic and early Mesozoic Eras, this region was folded, lifted and eroded by tectonic forces as Earth's Continents merged into Pangea and then rifted apart.

Among the sedimentary rocks that formed within the ancient rift valley was a thick layer of hard quartzite sandstone; resistant to erosion, this Table Mountain Sandstone now outcrops as the steep cliffs of Table Mountain and the Cape Fold Ranges of western South Africa.  Of note, the western end of this sandstone formation is now found in Argentina, separated from its South African segment as the Atlantic Ocean opened, some 150 million years ago.

Sunday, October 28, 2018

First Goldeneye, Last Osprey?

On this cool, sunny morning along the Colorado Front Range, I visited South Platte Park.  There I encountered a good variety of waterfowl, including the first common goldeneye of the season; the attractive male was fishing by himself on the clear waters of Eaglewatch Lake.  I was also fortunate to observe a lone osprey, perhaps the last one I will see at the Park this year.

Common goldeneyes breed across Alaska and Canada and winter primarily in coastal areas of the Pacific Northwest, the Canadian Maritimes, New England and the mid Atlantic Region.  Though less common, others winter on lakes across most of the U.S. and at least a few dozen spend the colder months at South Platte Park, feasting on a wide variety of aquatic creatures, from invertebrates to crustaceans and small fish.

Ospreys, on the other hand, are summer residents here and a pair have been nesting at the Park in recent years.  More common along the North American coasts, in the Pacific Northwest and in the Great Lakes Region, these "fish hawks" head for southern shores during the colder months and I suspect that this morning's visitor was on his way.

Friday, October 26, 2018

The Therapeutic Nature of Writing

Those who write, especially those who compose fiction, essays or poetry, know that it is a difficult task; indeed, finding the right words or selecting content that is both interesting and inspiring can be frustrating.  However, I have found that writing is a therapeutic process, forcing the author to confront their own experience, beliefs and biases.

Telling a story or persuading readers is more than an intellectual endeavor, it is an emotional one.  While all humans, consciously or subconsciously, attempt to bury life events that were especially painful, embarrassing or emotionally-charged, writers must actually draw on such experiences to make their content "real" for those who consume it.  Though their work may not be autobiographical, it is always infused with their own thoughts, emotions, convictions and insecurities.

Writers certainly understand these points and most would admit that the writing process is essential to their sense of well-being.  Many psychologists and psychiatrists use writing as a form of therapy and non-writers might want to personally investigate the therapeutic benefits of this human endeavor; it is, after all, a low risk and potentially enjoyable form of self-discovery.

Wednesday, October 24, 2018

The Autumn Crier

A great horned owl was hooting outside our bedroom window last night, the first calls I have heard this season.  Like a town crier with an important message, he seemed to be warning the locals that, despite our current mild weather, winter is on the doorstep.

Of course, this vocal fellow was merely responding to his own hormones, unleashed by the waning period of daylight; the long, chilly nights are good for hunting and his mating season is fast approaching.  At this point, in mid autumn, he is just announcing his presence and his target is not the human ear.

No doubt, his hooting (and that of his eventual mate) will increase in the coming months.  Unfazed by frigid nights and heavy snow, he will relish the dark, quiet season of nature's year.

Tuesday, October 23, 2018

The Nature of Regret

When I hear someone say that they have no regrets in their life, I tend to be skeptical.  After all, regret, whether major or minor, is part of human nature, a product of our large, complex brains.  Prone to ruminate, we often regret past decisions, actions or comments, whether justified or not.

This tendency to live in our past often makes us less happy in the present.  Judging ourself through the prism of hindsight, we are not always fair-minded, having buried the context in which past choices were made; neither do we always acknowledge the benefits that arose from those actions.  It's one thing to regret having made an insensitive remark and quite another to regret major life decisions.

Unfortunately, we are not always honest or reasonable when we review our past; whether we admit it or not, we all harbor regrets.  The real issue, it seems to me, is whether we let those regrets impact our current happiness and relationships.

Monday, October 22, 2018

Leaf Armies

Here on our Littleton, Colorado, farm, I do not bother raking the leaves.  While we have a large number of deciduous trees and shrubs, I'm inclined to let nature handle their autumn debris.  Besides, it can be entertaining, watching the leaf armies race across our driveway and "lawns."

In this semiarid climate, the leaves rarely get bogged down by precipitation; they may be stabilized by a snowfall for a day or two but the intense Colorado sun rapidly frees them to rustle across the landscape once again.  Eventually, the armies settle down beneath the shrub lines and wood borders, providing fertilizer for next spring's growth.

It's a win-win situation.  Entertainment and no work for me and natural nutrients for our trees and shrubs.  The mounded leaves also offer winter protection for many invertebrates, at least until they are discovered by the birds, mice, raccoons and skunks that visit the farm.

Sunday, October 21, 2018

Tourism and our National Parks

Anyone who has visited our National Parks in recent years has certainly noticed a dramatic increase in the tourist population.  The massive crowds detract from the serenity and, more importantly, have a significant impact on the natural ecology.  As a result, some Parks have begun to limit access and others will surely be forced to do the same.

Some might argue that tax-paying citizens own these natural preserves and that any limits placed on access is inappropriate if not un-Constitutional.  Of course, other citizens resent the protection of Federal lands altogether, favoring access for grazing, mining, drilling and "development."  In the end, we Americans will have to decide what should be protected for the benefit of future generations and for the welfare of our planet and its ecosystems.

Those seeking natural retreats without the tourist throngs should consider visiting our National Wildlife Refuges.  Relatively unknown to the general public and often devoid of the "comfort facilities" that most tourists seek, they offer some of the greatest wildlife spectacles on the planet.  Some of the more popular refuges can get a bit congested during peak viewing seasons but it's nothing like the urbanization of our National Parks.

Friday, October 19, 2018

Colorado's Indian Summers

Following a snowstorm and a hard freeze, we are back in the warm, sunny days and crisp, cool nights of mid autumn, the classic "Indian Summer" that outdoor enthusiasts relish; here along the Front Range, we expect highs in the upper 60s and 70s (F) over the next few days.  Now that most pesky insects have been killed, hiking, birding and other outdoor activities are especially pleasant.

Defined as the warm period following the first hard freeze, Indian Summer sets the stage for at least six months of similar weather patterns along the Front Range urban corridor.  This undulating cycle of mild sunny days following a brief period of cold and snow tends to occur from October to early May; in essence, we experience a continuous series of Indian Summers.

Unlike most regions of the country, the Colorado Front Range climate is not characterized by four distinct seasons.  Rather, we have summer and winter, battling for dominance for much of the year; while plant life cycles, the changing angle of solar radiation, astronomical events, mammalian ruts and bird migrations offer some justification for identifying spring and fall in Colorado, the weather itself is usually summer-like or winter-like.  Indeed, layered clothing is a must for outdoor adventure here since we often experience both summer and winter in the same day!

Wednesday, October 17, 2018

Mountain Bluebirds off to the Desert

Mountain bluebirds, among the most attractive songbirds in North America, breed throughout the Intermountain West, from Northern Canada to Northern Arizona and New Mexico.  During those warmer months, they favor open areas with scattered trees and may be observed on meadows of the foothills and mountains, in pinyon-juniper woodlands or on the alpine tundra near timberline.

Come fall, they descend to lower elevations, heading for the Desert Southwest or the Southern High Plains.  On their journey, they often travel in large flocks, adding color to the drying autumn landscape of the Colorado Piedmont and the volcanic terrain to our south.

Following the first major snowstorm of the season, flocks of mountain bluebirds have been spotted all across Metro Denver and I was fortunate to observe ten of those beautiful migrants at South Platte Park.  By March, when snowstorms still lash the Front Range, they will return, fueling what little spring fever may arise during that fickle season here in Colorado. 

Sunday, October 14, 2018

First Snowstorm of the Season

As predicted, a potent cold front dropped southward through the Rockies and Northern Plains last night.  Following yesterday's warm, sunny weather, snow developed overnight and continues along the Front Range this morning; up to six inches of accumulation is expected.

While our spring, upslope storms are usually triggered by Pacific storms that move eastward along the Colorado-New Mexico line, autumn and winter snowstorms most often result from cold fronts that plunge down from Canada.  Driven by cold high pressure, clockwise winds along the leading edge of this dome sweep moisture in from the Great Plains, producing the snowstorms.  As the dome moves eastward or southward, the Front Range upslope breaks down, the snow subsides and clear, cold high pressure grips the region.  Eventually, on the backside of the dome, southerly winds sweep warmer air across the Front Range urban corridor and mild conditions persist until the next cold front arrives.

Such undulating weather is common here throughout the colder months, as warm, sunny periods alternate with snowstorms.  It is an invigorating climate and those who live here welcome the snow; after all, it is primarily responsible for keeping our semiarid environment from becoming a desert.

Saturday, October 13, 2018

Natural Solutions to Climate Change

While our President and his Administration reject the evidence and ramifications of global warming, we must do what we can to protect our home planet for future generations and for all life that shares Earth's ecosystems.

Though we are all aware of efforts to wean mankind from fossil fuel, it is also important to understand that nature can play a major role in reducing atmospheric carbon dioxide.  For an overview of this concept and how you might participate, visit the websites of Nature4Climate and The Forgotten Solution, sponsored in part by The Nature Conservancy.

Of course, we can also make a difference by reducing our personal energy consumption, by planting trees, by supporting conservation groups and, most importantly, by voting Trump and other climate change deniers out of office.

Friday, October 12, 2018

The Other Autumn Warbler

Birders who reside across central latitudes of the U.S. are never surprised to see yellow-rumped warblers in October; indeed, these hardy insectivores even stay for the winter in some parts of the Midwest.  But there is another warbler that is also slow to head for southern climes and may still be encountered in mid autumn: the orange-crowned warbler.

Breeding in open woodlands or in the deciduous understory of coniferous forest, orange-crowned warblers summer across Alaska and Canada and southward through the Western mountain ranges.  Come fall, they head for coastal areas of California and the Southeast or farther south to Mexico and the Caribbean.  En route they generally appear alone, scouring shrubs, thickets and the lower branches of trees for a wide variety of insects; like many insectivores, they occasionally visit suet feeders and may consume berries if their insect prey is scarce.

A lone orange-crowned warbler has been visiting our Littleton farm the past few days, feeding with chickadees and yellow-rumped warblers.  I doubt he'll stay much longer but, unlike most warblers that are well south of the freeze line by now, our visitor has already shrugged off several frigid nights and a few periods of snow.

Thursday, October 11, 2018

Harriman Lake Park

Harriman Lake is a 67 acre water storage reservoir in southwest Metro Denver, fed by an irrigation canal; a 1.7 mile graveled trail leads around the lake and past several wetland areas, offering broad views of the open water and of the Front Range foothills to the west.  Access to the Park is via a parking lot on the north side of Kipling Parkway, a short distance south of West Quincy Ave.

Though modest in size, Harriman Lake is a magnet for resident and migrant waterfowl and is one of the region's best locations for viewing and photographing those species.  Last week, as a cold front loomed to the northwest, my wife and I visited this Park; on our walk around the lake we saw an excellent variety of waterfowl, including the first American coot, ruddy ducks and redheads that I had observed this season.  A lone American white pelican lounged on the shore, double-crested cormorants fished on the lake and pied-billed grebes dove with the coot in the marshy shallows.

While naturalists and birders usually prefer more secluded nature preserves, far from the trappings of human civilization, wild creatures are often content to utilize less pristine habitat; as long as they feel safe and their preferred food is abundant, they will stick around.  Harriman Lake, just southwest of a busy intersection, offers an excellent example; it certainly appeals to waterfowl.

Wednesday, October 10, 2018

The Surge Coast

The entire Gulf Coast of Florida, from the Keys to Pensacola, is especially vulnerable to storm surge as hurricanes and tropical storms come ashore.  Counterclockwise winds push water toward the coast on the "right" side of storm's eye, forcing it across the low country and up the coastal rivers.

This process is accentuated along the Florida Gulf Coast due to the topography of the Gulf itself.  A broad shallow area, representing the west portion of the Florida Platform, parallels the State's Gulf Coast; as ocean water is swept in by the storm, it cannot displace downward and builds to destructive depths across the barrier islands and coastal lowlands, leveling structures and flooding the landscape.

Hurricane Michael, now a Category 4 storm, is poised to come ashore near Panama City this morning.  Storm surge is expected to reach 13 feet or more in some parts of the Great Bend before the hurricane and its remnants cut a swath of destruction across the eastern Panhandle, south Georgia and the Carolinas.

Tuesday, October 9, 2018

Tropical Kingbird in Colorado

Several days ago, a tropical kingbird was sighted in southwest Metro Denver, just west of South Platte Reservoir.  As one might expect, it has since attracted birders from throughout the region and I made my pilgrimage yesterday afternoon (after all, the location is just a few miles south of our Littleton farm).

Though the weather was far from tropical (cloudy, cold and misty), the large, attractive flycatcher was gleaning insects from the side of a building, stopping to rest on a barbed wire fence.  Joined by a Say's phoebe and a small flock of house finches, the rare vagrant seemed unfazed by the raw, autumn weather.

Permanent residents of Mexico, Central America, northern South America and extreme South Texas, tropical kingbirds also breed in southeastern Arizona.  While most birds withdraw toward the Tropics in winter, some have long traveled northward along the Pacific Coast; most stop in California but some have been sighted in the Pacific Northwest, as far north as southeast Alaska.  Other vagrants have turned up in valleys of the Intermountain West, along the Atlantic and Gulf Coasts and even in the Great Lakes region.  Most of the far-flung vagrants have been encountered during the spring or fall; controversy remains as to whether some of the sightings (especially those in the East) were of Couch's Kingbird.

Monday, October 8, 2018

A Hermit visits the Farm

Yesterday, while wandering through our Littleton farm, I noticed movement behind a row of shrubs.  Standing my ground, I waited several minutes before the stranger emerged and, though he remained in the shadows, I knew at once that he was a hermit thrush.

Summer residents across Canada and southward through the mountains of North America, this hardy thrush is slow to migrate southward or to the coasts, feeding on berries once the insects disappear.  Like his cousins, he prefers to feed on or near the ground, running into the cover of shrubs or thickets if disturbed.

While most hermit thrushes end up wintering across the southern U.S. or along the coasts, some linger in colder regions if adequate food is available.  Yesterday's visitor was the first I have seen on our farm and, if we have another mild winter, he may just stay for the season.

Sunday, October 7, 2018

Snowbirds Drift In

On this cloudy and chilly afternoon, the first dark-eyed juncos of the season appeared on our Littleton, Colorado, farm.  They were members of the Oregon subspecies and had arrived just in time.

Commonly known as snowbirds, juncos are small, hardy songbirds that summer up in Canada or in the mountain ranges of North America.  Fond of cool weather, they winter primarily across the northern half of the U.S. and often arrive with the first snows of autumn.  The latter fact is especially true here in Metro Denver and, within the next few weeks, our farm will host dozens of these winter residents.  Gray-headed juncos descend from the Front Range and the slate-colored and Oregon subspecies arrive from more northern latitudes; on occasion, white-winged juncos also visit from the Black Hills region of western South Dakota.

All four subspecies are classified as dark-eyed juncos and are often observed in suburbs and along country roads, their white outer tail feathers obvious as they scatter toward cover.  I am pleased to have them back on our farm and I appreciate the weather warning that they bring....snow flurries are expected tonight or tomorrow. 

Friday, October 5, 2018

Cormorant Exodus

Yesterday morning, beneath a clear blue sky and enveloped in cool autumn air, I visited South Platte Park.  A steady, southeast wind kept many of the songbirds under cover and the waterfowl numbers remained well below par for early October.  Fortunately, a massive parade of double-crested cormorants made the visit especially memorable.

Beginning about 8 AM, small flocks of cormorants appeared overhead, flying southward through the South Platte Valley.  They were followed by a steady line of cohorts, numbering 87 birds in all.  I can only assume that these "fish crows" are beginning their exodus to southern lakes or the Gulf Coast, perhaps stopping by Chatfield Reservoir for a day or two of fishing before moving on.

Their exodus is surely triggered by the waning sunlight hours but they might also sense a change in the atmospheric pressure as a cold front gradually approaches from the northwest.  We expect cooler, rainy weather in the coming days and possible snow showers by early next week.  While that would not threaten the welfare of these hardy fishermen, their lives are governed by instinct and they "know" it's time to travel south.

Thursday, October 4, 2018

Great Black Wasps

Yesterday afternoon, while sitting outdoors, my wife and I noticed a large black wasp that was scurrying across the driveway.  It soon became evident that it was dragging a dead or paralyzed cricket toward a mulched area next to the pavement.

This was a great black wasp, found across North America, from southeastern Canada to Mexico; it is a resident of all of the Lower 48 States except Washington and Oregon.  Females dig a hole in the soil in which they lay a single, fertilized egg; they then capture a grasshopper, cricket or katydid, paralyze it and place it in the nest cavity, repeating the process multiple times throughout the warmer months.  Once the egg hatches, the larval grub feeds on the hapless victim until it is mature enough to pupate.  Adults emerge from the pupae and spend much of the summer feasting on nectar; in the process, they pollinate a variety of flowers.

Of course, most of this life cycle is unnoticed by humans.  Gardeners may encounter great black wasps as they move among flower beds but yesterday's encounter was pure luck on our part.  Unaggressive, these wasps rarely sting humans (unless threatened) and play an important role in controlling grasshopper and cricket populations.  Their means of feeding larvae may seem cruel but nature's web of life is not always pretty to behold.

Wednesday, October 3, 2018

Milkweed Bugs

Walking through South Platte Park the other day, I looked ahead and saw bright red masses on the side of the trail.  Initially thought to be some type of fungus or slime mold, I found that they were large clusters of small bugs.....milkweed bug nymphs to be exact.

Found throughout North America, from southern Canada to Mexico, these true bugs feed exclusively on milkweed plants.  Eggs are repeatedly laid on the plants by the adult female; during her month of adulthood, she will lay thousands of eggs.  Upon hatching, the nymphs molt five times before reaching the adult stage; each nymph phase is about 6 days in length.  While the elongated adults have a striking black and orange pattern on their dorsal surface, the younger nymphs are bright orange-red.  Both adults and nymphs may cluster where milkweed seed pods are abundant and their bright coloration warns potential predators that they are toxic (due to compounds ingested from milkweed sap).

Unlike most insects, milkweed bugs overwinter as adults; those that mature in northern latitudes must migrate to southern climes or find a protected site in which to wait our the season.  Considering the date, most of the nymphs that I encountered will likely not reach the adult stage before cold autumn weather envelops the Front Range. 

Tuesday, October 2, 2018

A Forty Degree Swing

Autumn is the season when those of us along the Colorado Front Range often experience a 40 degree (F) temperature swing in the course of a day, awakening to a temperature in the upper thirties and basking in warmth near 80 degrees by mid afternoon.  Such broad temperature ranges are common in arid and semiarid regions across the globe, especially those that lie at relatively high elevation in the Temperate Zone.

By October, the longer nights, high elevation and dry air augment heat radiation, permitting overnight temperatures to fall near freezing.  During the day, intense sunshine, dry (dense) air and, on some days, a downsloping wind push afternoon highs into the seventies or eighties.

Of course, potent cold fronts or a persistent upslope flow may disrupt this cycle, as is forecast to develop later this week.  By early next week, daytime highs may be within 10 degrees of the overnight low and the first snow showers of the season are expected to dust the urban corridor. 

Monday, October 1, 2018

Truth and Politics

Almost every human endeavor relies on truth (at least as defined by the latest scientific evidence) in order to offer products and services that are safe, reliable and competitive.  A few careers (fiction writing comes to mind) may be independent of truth while some, especially those that peddle mysticism (e.g. organized religion), are threatened by science-based truth.

Politicians, on the other hand, maintain a fuzzy relationship with truth.  Focused on the demands of their constituents and on their own re-election, they pick and choose what truths they publicly believe.  Those who represent regions with coal, gas and oil production play down evidence of global warming while those who hail from agricultural areas are loathe to acknowledge the environmental pollution that results from farming and ranching activity; many other examples could be offered.

Worse yet, some politicians seem willing to lie or to dismiss the truth in order to further their political or personal agenda.  Our President offers an extreme example and the ongoing efforts to elect Brett Kavanaugh to the Supreme Court reveal that Conservatives (including Evangelicals) are willing to overlook false testimony in order to achieve their ultimate goals.  Of course, truth will eventually prevail but damage (perhaps irreversible) to our government, to our environment and to our society may occur beforehand.