Posts

Showing posts from March, 2016

Morning Sunshine, Afternoon Snow

Following thunderstorms last evening, we awoke to bright sunshine in Metro Denver this morning.  Radio broadcasters, responding to a forecast of rain and snow showers and presumably looking out their small studio windows, scoffed at the predictions of local meteorologists.

Had their window offered a broader view, however, they might have been less dubious.  While sunshine bathed the city, the peaks of the Continental Divide had disappeared within a dense band of clouds that extended eastward across the northern horizon.  By noon, the front was closing in on Denver but the warm sunshine had sent many locals to parks and outdoor cafes for their lunch.  But within another hour, the cold front swept through the Metro area, unleashing cold northerly winds and scattered snow showers.

As I write this post, the storm is centered over southern Nebraska, too far north for a classic upslope snowstorm in Denver; nevertheless, periods of snow are expected to persist through the evening hours.  As …

Highway through Early Spring

Returning to our Littleton, Colorado, farm, I headed west on Interstate 70 (my usual and most efficient route).  Redbud trees adorned the woodlands of Missouri and eastern Kansas while turkey vultures and red-tailed hawks sailed in the clear blue sky.  All across the Great Plains, newborn calves frolicked near their placid mothers, oblivious of events to come.

In the Flint Hills of Kansas, a proscribed burn had escaped control in the strong, southerly winds; flames licked along the highway and water trucks raced toward the leeward side of the charred grassland.  Just south of Russell, cormorants and white pelicans crowded a small lake; near Oakley, a bevy of female turkeys gathered to watch their suitors display and, farther west, at Goodland, ring-necked pheasants foraged along the Interstate.  Despite afternoon highs in the lower 70s F, residual pockets of snow graced the High Plains, increasing as I approached the Front Range; great-tailed grackles argued at a rest stop in Arriba, …

Joining eBird

An avid birder for 40 years, I have generally shunned the traditional habit of creating life or regional lists to document my success; rather, I simply record the date and site of "first sightings" in my field guides; of course, various posts in this blog also document many of my encounters.  And though I regularly participate in seasonal songbird and waterfall counts, sponsored by local nature centers or national conservation organizations, I have not personally contributed to the collection of data on avian populations.

Having become familiar with eBird, based at Cornell University, I have decided to join their effort to compile information on bird populations across the globe.  Taking in data from birding groups and individual birders, they are monitoring the health and range of each species, thereby documenting the effects of human activity and helping to determine what conservation policies might be most effective.

My plan is to focus on three birding hotspots that I vi…

Pelicans at Sunrise

Arriving at Eagle Bluffs Conservation Area just before sunrise, my friend and I encountered a large flock of American white pelicans, lounging on a sandbar and illuminated by the glow of a nearly full moon.  As the sun crept above the river hills to our east, the pelicans began to stir, leaving in groups to flap and glide above the refuge pools.

During our two hour visit, more pelicans were encountered (at least 300) and flocks of these magnificent birds continuously moved above the floodplain, their wings reflecting the bright morning sun.  Joined by bald eagles, double-crested cormorants, Canada geese, various ducks, pied-billed grebes, great blue herons and a mix of shorebirds, the pelicans were certainly the highlight of our visit.

On their way up the Missouri River, American white pelicans attract birders to Eagle Bluffs every spring; they generally stop at the refuge from mid February through April though non-breeding birds may be encountered throughout the warmer months.  Heade…

After Humans

Our sun ignited about 5 billion years ago (8.7 billion years after the Big Bang) and our home planet had formed by 4.6 billion years ago.  Life first evolved in the primordial seas of Earth about 3.6 billion years ago and, through the process of natural selection, has since diversified into the millions of plant and animal species that we find today; we humans did not appear until 150,000 year ago, at the earliest.

Since life appeared and began to diversify, the great majority of species have become extinct, some as "failed" dead-end species while others morphed into more viable species before they died out; the volcanic and sedimentary rocks of our planet are replete with fossils and preserved impressions of extinct species, most of which we have yet to discover.  We humans, endowed with a large brain, imagine that we are a chosen species, the endpoint of evolution on Earth, destined to rule the planet until our God comes to whisk us from our animal life.  Unfortunately, th…

Changing Seasons

While the calendar and waxing daylight indicate that we have just passed from winter into spring, the weather suggests otherwise.  Following two warm days, with afternoon highs in the 70s (F), a cold front approached last evening, igniting thunderstorms in central Missouri just before 11 PM.

Behind the front, temperatures have cooled dramatically; today, the afternoon high is forecast to be in the forties.  Though we escaped the snow that fell in a swath from Colorado to Ontario, we can expect a gray overcast with scattered showers and gusty winds as the storm pushes off to the northeast.  From a weather point of view, we have gone from late spring to late winter.

Of course, such episodes are not unusual in the course of a Midwestern spring.  A restless jet stream keeps weather patterns unsettled and the higher sun fuels powerful storms, especially as we move into April.  This rapid cool off will be followed by a less abrupt but steady warm up; tomorrow's high is expected to reach…

American Golden Plovers

Six American golden plovers fed on a mudflat at Eagle Bluffs Conservation Area this morning, having stopped to rest and feed on the Missouri River floodplain as they head for the Arctic tundra of Alaska and Canada.  These long-distance migrants leave their Arctic breeding grounds by late summer, traveling to grasslands of Patagonia (in southern South America) for the northern winter; this journey is achieved without rest stops as the plovers travel off the East Coast of the Americas.

Come spring, American golden plovers migrate northward through the heart of North America; it is then (primarily in late March or early April) that they may be encountered on fields or mudflats, often in large flocks.  After feeding on invertebrates and seeds, they continue their journey to the north and will be nesting on the tundra by late spring.

This morning's visitors had not yet molted to their summer plumage but they were nevertheless attractive birds.  Of course, their beauty is magnified by o…

Engagement & Influence

As I write this post, President Obama is in Cuba, meeting with Raul Castro.  Many Americans, including many Cuban immigrants, oppose this political and cultural engagement, arguing that it lends support to a dictatorship, stifles dissent and gives credence to a corrupt system of government.

Many of us, however, applaud the President's initiative, believing that engagement is vital to fostering change in Cuba.  A prolonged course of sanctions has produced no effect; hopefully, increasing commerce will offer opportunities for the Cuban people (without destroying their culture) and, most importantly, shine a light on the oppression and corruption that will surely persist.  Over time, open communication and economic pressure will fuel a transition to democracy.

One hopes that a similar approach might be utilized in dealing with other oppressive regimes across the globe, including some (e.g. North Korea) that currently seem unreachable.  Simply put, our choice is political and economi…

March Loners

While many birds gather in flocks during March, preparing for or engaging in migration, and others begin to congregate at favored nesting sites, a few species usually turn up alone as they move through the American Heartland.  In my experience, horned grebes and fox sparrows are among these March loners.

Visit lakes and wetlands in March and you are likely to see sizable flocks of geese and ducks; one might also encounter large congregations of American white pelicans, various shorebirds, coot and double-crested cormorants.  Pied-billed grebes often appear in pairs or small groups and even uncommon migrants, such as scoters, tend to migrate in flocks.  Horned grebes, on the other hand, are usually found alone, diving from the calm surface of a lake for hours at a time; on their way between southern lakes and coastal bays to breeding grounds across Alaska and the western half of Canada, their stopovers in the American Heartland tend to be brief.

In suburban areas, sparrows and juncos a…

Cormorant Caravan

As I drove across the Glaciated Plain of Illinois this morning, a linear flock of double-crested cormorants passed overhead, on their way to breeding grounds farther north.  After wintering on southern lakes or along the Gulf Coast, the inland cormorants of North America head for reservoirs and freshwater lakes from the Great Lakes Region to the Intermountain West; most breed across the Northern Plains of the U.S. and Canada, east of the Rockies.

Colonial nesters, double-crested cormorants often choose wooded backwaters where they build their bulky nests in drowned trees; others opt for barren islands where nests are placed directly on the ground.  Heavy-boned and harboring less oil in their plumage, cormorants are excellent divers, feeding on a wide variety of fish; when not hunting, they often rest on tree limbs, channel posts or other man-made structures with wings spread to dry.

Today's flock was a welcome sight in the clear blue sky, just another sign that spring is gaining m…

New Arrivals at Eagle Bluffs

Greeted by brilliant sunshine, warm air and the purple haze of henbit on many of the barren fields, I made a quick trip through Eagle Bluffs Conservation Area this morning.  Bird sightings were generally unremarkable, including the usual mix of bald eagles, red-tailed hawks, northern harriers and common species of waterfowl; red-winged blackbirds, killdeer and upland chorus frogs provided a steady background chorus.

A flock of female buffleheads was a bit unusual for mid March and a pair of pied-billed grebes fed with the ducks and Canada geese.  New to the crowd were a few double-crested cormorants, the first that I have encountered in Missouri this season; some will be seen at Eagle Bluffs throughout the warmer months but most will move on to more northern breeding grounds.  The other new arrival was an eastern phoebe, hunting in woodlands near the Missouri River; always the first flycatchers to arrive from the south, eastern phoebes favor riparian habitats where their prey is espec…

The Vosges Massif

Though I have been more interested in the evolution and dispersal of our species than in my own family's genealogy, I decided to investigate the Alsace-Lorraine region along the France-Germany border, an area from which my paternal grandfather's family had immigrated.  Looking at the map, my attention was immediately drawn to the Vosges Massif, west of the Rhine Valley.

Back in the Carboniferous Period, some 300 million years ago (MYA), a mountain range towered above what is now the France-Germany border region.  Throughout the Mesozoic, natural forces decimated these mountains, covering them with erosional and volcanic debris.  Then, late in the Cretaceous (about 70 MYA), the Alps began to crumple skyward; in concert, the roots of the above ancient range bowed upward, forming a geologic anticline, oriented SSW to NNE across the current border of France and Germany.  In the late Eocene and early Oligocene (some 40 MYA), faulting through this uplift, in addition to east-west st…

First Tide of Blue Wings

On this cool, misty morning in central Missouri, the first tide of blue-winged teal had arrived at Eagle Bluffs Conservation Area, on the Missouri River floodplain.  Common summer residents across much of North America, these small, attractive ducks winter along the Gulf Coast, in Central America and in northern South America.

Since most migrate long distances, blue wings are among the last species of waterfowl to arrive in the spring and among the first to depart in autumn; their numbers generally peak at Eagle Bluffs in late September and mid April.  The great majority breed in the prairie pothole region of the Northern Plains (from the Dakotas into Canada) but smaller numbers nest throughout Temperate latitudes of the Continent, favoring shallow lakes and riverine wetlands.

Their appearance at Eagle Bluffs this morning is just the latest sign that spring is unfolding across the American Heartland, an erratic and uneven process that will take two months to complete.  By then, these …

A Promise Seldom Kept

After a week of mild, sunny weather and a single episode of heavy rain, color has returned to the landscape of central Missouri.  The grays and browns of winter are giving way to greening lawns and flowering plants.  Among the early spring bloomers are red maples, wild cherries, forsythias and several species of magnolia; the flowers of periwinkle, crocuses, daffodils and hyacinths adorn the flower beds and, much to the chagrin of lawn masters, the first crop of dandelions glow from every patch of grass.

This burst of spring seems to promise that winter has retreated to the north, not to return until the waning daylight of November, and that our path to the balmy days of May will be a steady, carefree climb.  Time to get out the gardening tools and mothball the winter coats!

Of course, nature makes no such promise; she is fickle and erratic, especially in March and April.  The conviction that spring weather is here to stay is a human fabrication, the product of hope and denial; while …

Humboldt the Ecologist

In the course of reading The Invention of Nature, by Andrea Wulf (see Getting to know Humboldt), I have come to learn the important role that Alexander von Humboldt played in the field of ecology, theretofore an unacknowledged science.  Famous for his intrepid exploration of the tropics in Venezuela and the Andes of Colombia and Peru, Humboldt's major gift to humanity may have been his insights regarding the unity of nature, the interdependence of ecosystems and the effects of human civilization on the health of our natural environment.

Energetic, enthusiastic and inquisitive, he made detailed records of his discoveries and, in the course of that process, took note of similar ecosystems across the globe, related by latitude and/or elevation.  Indeed, to my knowledge, he was the first explorer to develop the concept of life zones, thereby emphasizing the effects of climate on the resident plants and animals.  He also observed and reported on the negative effects that human societie…

The Political Animal

Immersed as we are in the current Presidential race (or simply binge-watching House of Cards), most of us develop a negative image of career politicians (see The Nature of Politics).  Unfortunately, as much as we are loathe to admit it, there is a bit of a politician in each of us.

Consciously and subconsciously focused on our personal welfare and survival, we are selective in our comments, protective of our image and manipulative in our efforts to influence others.  We want to be liked and admired.  We hope to be hired, advanced and rewarded for our work.  And, of course, we strive to be loved.

Fortunately, most of us devote ourselves to the challenges of relationships, parenting and our chosen career, achieving satisfaction without the personal need for power and celebrity.  We choose to relegate those perks to politicians; though we might prefer statesmen (or stateswomen), we accept the fact that democracies cannot function without these elected representatives.  In the course of t…

The Octopus Family

Members of the Class Cephalopoda within the Phyla Mollusca, about 300 species of octopus are found in Temperate and Tropical seas across the globe.  Having first evolved during the Carboniferous Period (some 300 million years ago), they now inhabit a wide range of ocean habitats, favoring coral reefs and rocky areas near islands, shelfs or seamounts.

While some grow to 5 feet in length and weigh up to 25 pounds, most species are much smaller; on the other hand, the Giant Pacific octopus may reach 30 feet in length and weigh up to 600 pounds.  All feed primarily on a host of marine crustaceans and mollusks and evade predation themselves by the use of camouflage, by swiftly retreating to a protective crevice within rock or coral and by releasing a cloud of ink that temporarily blinds and confuses the predator; should one of its eight arms be snared by an enemy, the octopus is able to regrow another.  Venomous saliva, employed to stun prey, is seldom used for self-protection; however, th…

Prelude to Storms

As the storm system that brought rain and mountain snows to California dips southeastward, a deep atmospheric trough and upper level low are developing across the Western U.S.  Ahead of this system, warm, moist air is moving northward from the Gulf of Mexico, priming the Southern Plains and lower Mississippi Valley for thunderstorms and flooding rains.

Here in Missouri, we expect an afternoon high of 70 degrees F under cloudy skies.  Thunderstorms are forecast to arrive overnight though severe weather will likely remain to our south; indeed, a tornado watch has been posted for much of Texas and States to its north and east.

In addition to the severe weather, copious rainfall is expected in the south-central U.S. over the next few days as the upper level low stalls over Texas, directing a plume of Gulf moisture and imbedded thunderstorms across the region.  Up to a foot of rain is forecast for Louisiana and Arkansas before the system breaks down and moves off to the east.  Flood season

First Spring Shorebirds

Here in Missouri, killdeer are permanent residents, upland sandpipers, spotted sandpipers and American woodcocks are summer residents and common snipe are winter residents.  Other shorebirds are migrants, passing through the State on their way between northern (often Arctic) breeding grounds and wintering grounds on southern beaches, on Caribbean islands or in Central or South America.

This morning, at Eagle Bluffs Conservation Area on the Missouri River floodplain, I encountered flocks of short-billed dowitchers, the first migrant shorebirds that I have observed this season and among the earliest that I have ever encountered in Missouri; indeed, the spring shorebird migration generally begins in late March in our region, peaks during April and tapers off through the first half of May.  Of course, there are always exceptions and these dowitchers, headed for taiga lakes and wetlands across Alaska and Canada, may have to endure some nasty March weather.

Then again, birds that breed acro…

Carolinas on my Mind

Attempting to read outside yesterday morning, my efforts failed once again.  While the sunny, cool weather had coaxed me onto the deck, it also invigorated our local avian residents.  Most conspicuous were the Carolina wrens.

As if dueling for attention, several of these vocal birds repeatedly called from various corners of the property.  Two others intermittently hopped across the deck, disappearing into the adjacent shrubbery.  Needless to say, my adventures with Alexander Humboldt were placed on hold.

Though not well known to non-birders, Carolina wrens provide much of the background noise in suburbs of the Eastern U.S.  Their loud, ringing calls and melodies, heard in all seasons, become intense in early spring as their breeding season approaches.  Easily identified by their white-eye stripe, thin, curved bill and raised tail, these small reddish-brown and buff-breasted birds are aggressive for their stature and especially noisy for their size.  When they are about, outside readin…

The Nature of Invertebrates

Defined as multicellular animals that do not possess a vertebral column, an internal skeleton or a cranium, invertebrates represent 95% of all multicellular animal species on Earth; though unicellular life first evolved in primordial seas about 3.6 billion years ago, marine invertebrates did not appear until 800 million years ago (near the end of the Precambrian Era).  Vertebrates are grouped within one phyla (Chordata) and are represented by about 66,000 species; by contrast, invertebrates are classified within 33 phyla and are represented by more than 1.3 million species.

The largest invertebrate phylum is Arthropoda, which includes more than 1.1 million species of insects, spiders and crustaceans.  However, 14 invertebrate phyla are represented by various types of worms; the largest of these is Nematoda, which includes more than 25,000 species of roundworms.  Among the other invertebrate phyla are Porifera (sponges), Cnidaria (anemones, jellyfish, corals), Mollusca (slugs, snails, …

The Damp Chill of March

Here in the Midwest, the crisp, dry air of autumn is welcome after a long, hot summer and we take the frigid blasts of winter in stride, relishing the beautiful, snowy landscapes that they often produce.  But the damp chill of March, contrasting with periods of mild, spring weather, is perhaps the least appealing weather of the year.

Children of the Tropics, we humans love warm, sunny weather and welcome the rains of late spring and summer.  And we adapt well to invasions of cold, dry air, layering on clothes or retreating to our heated shelters.  But the cold rain and icy mist of early spring cut to the bone, discouraging outdoor activity.

Of course, it's our impatience for the colors, fragrance and mild conditions of late spring that most taints our image of March and its fickle weather.  Those of us who enjoy the waterfowl migrations of early spring more easily tolerate this sloppy period with its flooded landscapes and swollen streams; others take solace in March Madness, an e…

Getting to know Humboldt

As an enthusiastic naturalist for more than forty years, I have long been familiar with Alexander von Humboldt, a famous German naturalist (1769-1859) who is best known for his exploration of South America.  I have also been aware that a number of natural features, landscapes and species have been named in his honor; the cold Humboldt Current sweeps northward along the coasts of Chile and Peru, Humboldt penguins and Humboldt squid inhabit these rich ocean waters and, in my own country, Humboldt Peak, the Humboldt Range, the Humboldt River and the Humboldt Sink occupy northern Nevada.

My cursory knowledge of this renowned explorer and scientist will be greatly expanded over the next week or so as I read The Invention of Nature, by Andrea Wulf, a biography of Humboldt's life, travels, discoveries and philosophy.  Having read several positive reviews of this book, I purchased a copy with a gift card from my daughter and I look forward to the adventure ahead.

Indeed, fueled by our per…