Wednesday, January 31, 2018

Four Valleys in New Mexico

Yesterday morning, I left Roswell (in the Pecos River Valley) and drove west on Highway 380.  Climbing toward the Sacramento Mountains, I left the desert and soon reached grass-covered hills, passing Capitan Peak (10,083 feet) to my north.  The highway then entered steep-wall canyons before offering a spectacular view of Sierra Blanca (11,973 feet), the crest of the Sacramento Range.

At the Indian Divide, I left the Pecos River watershed and dropped into the Tularosa Basin, famous for White Sands National Monument and the massive Carrizozo basalt flow (5000 years old).  Highway 380 crosses the latter and several pull-offs are provided for close observation of this interesting volcanic landscape.  After climbing the Oscura Mountains, the road then drops into the Jornada del Muerto (Day of Death) which I hastened to cross.  A long, slow climb from there took me to the east wall of the Rio Grande Rift, lined with fault-block ranges, laccoliths and volcanic domes.

After descending to the valley floor and crossing the Rio Grande River, I took the opportunity to visit Bosque del Apache NWR, a renowned birding site, 8 miles south of San Antonio, New Mexico.  There I saw large flocks of snow geese, a fabulous diversity of waterfowl, bald eagles and, yes indeed, thousands of sandhill cranes! (See the last few posts).

Tuesday, January 30, 2018

Bitter Lake National Wildlife Refuge

Named for its large alkaline lake, Bitter Lake National Wildlife Refuge, in the Pecos River Valley, was established in 1937 to protect a vital desert oasis for migratory birds and resident wildlife.  As the Pleistocene gave way to the Holocene, some 10,000 years ago, the climate gradually warmed and flow through the Pecos River has gradually declined.  Fed by artesian springs from the Roswell Aquifer, the lakes, ponds and wetlands of the refuge have been managed by the use of levees and canals to ensure a range of salinity that provides diverse natural habitat.

Renowned for its large variety of dragonflies, Bitter Lake NWR also provides vital breeding habitat for least terns and snowy plovers.  A wide variety of shorebirds stop here to rest and feed during their spring and summer migrations while wintering sandhill cranes, geese (including Ross's geese), ducks, coot, bitterns and wading birds utilize the preserve from mid autumn to early spring.  Among other birds that breed here are greater roadrunners, northern harriers, American avocets, ladder-backed woodpeckers, Chihuahuan ravens, scaled quail, loggerhead shrikes, black phoebes, vermillion flycatchers and rock wrens.  Mammalian residents include six species of bat, kangaroo rats, porcupines, nutria, kit fox, black-footed ferrets, ringtails, bobcats and pronghorn, among others.

The refuge is best reached via Pine Lodge Road near the north edge of Roswell, New Mexico.  Drive east for 7 miles to the entrance and proceed to the Visitor Center (open Monday-Saturday, 8-4) for an overview of the landscape and its wildlife.  An auto tour loop, 6.5 miles long, is open everyday from dawn to dusk. 

Monday, January 29, 2018

Into the Land of Enchantment

South of Raton Pass, Interstate 25 drops onto the broad grasslands of northeastern New Mexico which are broken by volcanic hills, drained by the Canadian River and grazed by cattle and pronghorns.  Off to the west looms the southern portion of the Sangre de Cristo Range, its higher snow-capped peaks mostly hidden by mesas and foothills.  Today, ravens patrolled the highway, joined on occasion by a red-tailed hawk or kestrel.

A few miles beyond Las Vegas, I cut south on Route 84 which hugs the east wall of the Pecos River Valley before dipping to cross the river and then climbing back onto the High Plains; mountain bluebirds adorned this scenic route and a golden eagle scanned the valley from a roadside cliff .  Crossing Interstate 40, the road continues south as Route 219, undulating across rocky mesas and dry washes, covered with junipers and cholla cacti.  After angling southwestward to Vaughn, I drove the final 90 miles to Roswell on US 285, crossing some of the bleakest landscape on our Continent.

To renew my enthusiasm, I headed straight for Bitter Lake National Wildlife Refuge, about 7 miles east of town.  There I made two loops on the auto tour road, encountering thousands of snow and Ross's geese, a fabulous variety of ducks, a few white-faced ibis, two American bitterns, at least six northern harriers and a host of open-country songbirds.  Hanging around until dusk, hoping to match Teale's experience (see yesterday's post), I did observe at least a dozen flocks of sandhill cranes as they returned to the refuge; not exactly a spectacle but inspiring nonetheless.  More on the Refuge itself tomorrow.

Sunday, January 28, 2018

South to Bitter Lake

About 40 years ago, I read Edwin Way Teale's fourth book in his American Seasons collection.  Titled Wandering through Winter, it was researched in the winter of 1961-1962 and published in 1965.  On his journey across the country, accompanied by his wife, Teale stopped at Bitter Lake National Wildlife Refuge, just northeast of Roswell, New Mexico, in the Pecos River Valley.  The highlight of that visit proved to be massive flocks of sandhill cranes, returning to the refuge at dusk after feeding in nearby fields.

Teale's description of that spectacle has stayed with me over the years and I have long intended to visit Bitter Lake myself; that intention will finally be realized over the next two days.  Early tomorrow morning, I plan to drive south on Interstate 25, cross Raton Pass at the New Mexico border and proceed to Las Vegas, New Mexico, before cutting off on smaller highways that will offer a more direct route to Roswell.

As always, the anticipation of that road trip, including the new landscapes and interesting wildlife that I will encounter, lends a sense of excitement to the journey.  In the course of our brief lives, we best seek adventure whenever possible!  More on my travels and the refuge in the next few days.

Saturday, January 27, 2018

Love & Compatibility II

As a followup to yesterdays post on Marriage, I thought I might express my thoughts on love and compatibility, which play into the theme of marital discord and divorce.  Romantic love, it seems to me, is nature's way of stoking relationships and assuring the procreation of our species.  Strongly tied to sexual attraction, its intensity fades as relationships mature but persists when relationships fail to develop (see The Power of Love Denied).

In the case of ongoing relationships (marriage included), love evolves from the initial intensity of romance to a more subdued "loving partnership."  Love, however, does not ensure compatibility and it is the lack of the latter that most often ends relationships (even as love persists).  Love, if true, does not die but we may conclude that we cannot live together.

This goes back to my thoughts on marriage, which is generally fueled by intense romantic love.  Before we heed nature's call and start to produce children, we best take the time to decide if we are truly compatible.  Otherwise, the pain of divorce must be endured by innocents as well.  See also Love & Compatibility.

Thursday, January 25, 2018

Why Marriages Fail

Marriage, an Unnatural Union, is a social contract based on the commitment of two individuals.  Whether it is sanctioned in a church, on a beach or on the Vegas Strip, it is the mutual commitment that counts, not the ritual or the legal papers.  Unfortunately, this commitment is often made between two individuals who barely know one another and, as we all know, a large percentage of marriages fail.

In my opinion, couples should live together for at least two-three years before deciding to marry and certainly before choosing to adopt or conceive children.  Cohabitation uncovers traits in one another that might otherwise go unnoticed and forces us to face issues that are vital to the success of a marriage: compromise, mutual respect and the need for personal space, among others.

Of course, some might argue that we never truly know one another but a few years of living together should shake out most of the skeletons in our closets.  Religious persons will surely oppose this approach but anyone who follows this blog knows how I feel about religions; besides, faith does not protect couples from divorce.  Others might suggest that marriage itself is unnecessary, that the mutual commitment to one another is sufficient; to that point of view, I have no objection.

Wednesday, January 24, 2018

The Scourge of Mange

On this cloudy, cold, breezy morning, I was walking through South Platte Park when a pair of coyotes bolted from the riverside shrubs and loped across a snow-covered meadow.  One, endowed with a thick winter coat, was oblivious of the chilly wind, while the other was nearly hairless, sporting only a few tufts of fur along its back.  The latter animal was suffering from a severe case of sarcoptic mange.

Caused by a highly contagious, parasitic mite that burrows into the skin and causes intense itching, sarcoptic mange is a common disease of wild canines that can also develop in livestock and domestic pets; indeed, human scabies is essentially the same type of infestation.  Since wild canines usually live in packs, they are especially susceptible to sarcoptic mange which is generally fatal; death usually results from hypothermia and/or starvation.  Often shunned by their pack, severely infected coyotes cannot effectively hunt (due to their weakened condition and eventual blindness) and may turn up in residential areas to consume dog food, bird seed or garbage.

When we consider nature's beauty, we do not think of mangey coyotes.  But life in the wild can be cruel and nature is neither sentimental nor empathetic.  This morning's encounter was unsettling but also a reminder that the circle of life is not always pretty to behold.

Tuesday, January 23, 2018

Reliving History

This afternoon, I watched The Post, a superb film about the Nixon Administration's attempt to suppress publication of the Pentagon Papers by the New York Times and the Washington Post in 1971.  Of course, the Supreme Court ended up siding with the press and efforts to discredit Daniel Ellsberg, the source of the Papers, eventually led to the Watergate scandal and Nixon's resignation.

Back in 1971, I was applying to medical school and, given my low draft lottery number, was sure to be drafted if I did not succeed; fortunately, I was accepted to medical school and was spared a tour of duty (or worse) in Vietnam.  As a staunch opponent of the war, I may have ended up in Canada, at least until President Carter pardoned those who escaped to the north.

Now, 47 years later, we have another Nixonian President, suspicious of the Judicial Branch, contemptuous of the press and reckless with his foreign policy.  Hopefully, those who did not live through the late 60s and early 70s will watch this film and understand both the importance of a free press and the power of democracy.  The collective wisdom of the American people, which brought an end to the Vietnam War, must now be directed against an incompetent and dangerous President.

Sunday, January 21, 2018

Glorious Snow

After a nearly snowless winter so far, we are finally receiving a good dose of precipitation with this latest Pacific storm.  Starting overnight, the snowfall has reached about 4 inches on our Littleton farm and another 2-3 inches are expected before the system pushes off to the northeast.

The mountain snowpack, well below normal to date, is vital to our water supply and to the health of our regional semi-arid ecosystems; of course, the ski areas have been under-supplied as well and the less snow they receive the more snow they make, pulling water from the mountain streams.  The same scenario develops on the heavily populated Colorado Piedmont; the less rain and snow we receive through the winter and spring, the more precious water is used for irrigation.

The current storm will certainly not correct our deficit but we can hope that the atmospheric pattern has changed and that more beneficial storm systems will follow in the coming months.  Indeed, down here along the urban corridor, our heaviest snowfall tends to occur in March and April when moisture-rich upslope storms develop across the east slope of the Front Range.  For now, we'll enjoy the splendid scenery that this storm has produced, knowing that, beneath the surface snow, our drought persists.

Saturday, January 20, 2018

A Ruddy Morning

Participating in the January waterfowl count at South Platte Park this morning, I was fortunate to be placed in the Reservoir group, offering me another opportunity to observe the yellow-billed loon that has been wintering in Littleton.  While the temperature was mild, a strong south wind produced a choppy surface across the partly-frozen reservoir and an uncomfortable wind-chill on the levee.

A host of diving ducks joined the celebrity loon, including lesser scaup, buffleheads and common goldeneyes.  But the highlight of our count was a large number of ruddy ducks, small, stiff-tailed divers that are primarily winter residents along the Front Range.  After breeding in the prairie pothole country of the northern Great Plains and Western Canada, ruddies head for large rivers, lakes reservoirs and coastal estuaries across the southern U.S. and the Pacific Northwest.  There they are often seen in large rafts, bobbing in the waves and waiting for dawn or dusk when they tend to be most active.

Ruddy ducks dive to feed on both aquatic invertebrates and aquatic plants.  Despite their small size and comical appearance, they are aggressive and territorial during the breeding season and produce rather precocious youngsters that are independent within a couple weeks.  Though abundant in some coastal regions during the winter months, ruddies are always a welcome sight when they join more common waterfowl species on inland lakes and reservoirs.

Friday, January 19, 2018

Heat before the Snow

As Pacific storm systems move west to east across the U.S., a southerly flow develops ahead of the cold front.  In the central and eastern States, this flow draws warm, humid air up from the Gulf of Mexico, fueling rain and/or snow as the storm arrives.

Here along the Colorado Front Range, well west of the Gulf of Mexico, the southerly winds bring warm, dry air up from the Desert Southwest; downsloping winds east of the Continental Divide further heat and dry the air, often producing summer-like warmth in the middle of winter.  Today, we reached a near-record high of 67 degrees F as the front approaches from the Great Basin.

Once the cold front crosses our region, expected to occur by tomorrow afternoon, the winds shift from the north and the temperature plummets.  Depending upon the latitude of the central low, we may receive upsloping northeast winds, pulling in moisture from the Great Plains and leading to significant snow accumulation.  For Metro Denver, such an upslope snowstorm is most likely to develop when the central low moves long the Colorado-New Mexico line; currently, the forecast indicates that the storm will follow that pattern and snow is expected to develop by the early morning hours on Sunday.  Since the storm system is forecast to move rapidly to the northeast, our snow accumulation will likely be modest (though we could use a foot or more).

Thursday, January 18, 2018

The Taiga Shrike

This morning, while wandering through South Platte Park, I encountered a northern shrike, hunting from a barren tree in a lakeside meadow.  A native of the taiga across Alaska and Northern Canada, this species spreads south to the northern and western U.S. during the winter months when its smaller cousin (the loggerhead shrike) has moved on to warmer, more southern climes.

Generally solitary in winter, northern shrikes hunt from an exposed perch in a tree or tall shrub, dropping to snare songbirds or small mammals with its hooked beak and talons.  Its habit of storing excess prey by impaling it on thorns or barbed wire has earned it (and other shrikes) the nickname of "butcher birds."

By mid spring, northern shrikes return to their breeding grounds, favoring the open woodlands where boreal forest meets the Arctic tundra.  There they nest in stunted conifers, adding large insects to their diet and that of their growing youngsters; in a landscape of ephemeral pools and perpetual summer daylight, that prey is especially abundant.

Friday, January 12, 2018

Nature in Winter

We humans, native to the Tropics, tend to prefer warm, sunny weather.  Indeed, a significant portion of our population shuns winter altogether, venturing outdoors only to get the mail, walk the dog or fill the bird feeders.

Such disdain for winter is unfortunate since nature has much to offer during the colder months; if prepared with warm, layered clothing and appropriate footwear, one can take advantage of her gifts.  Those who brave the elements to visit nature preserves will find that non-hibernating mammals, invigorated by the chill and driven by the need for sustenance, are especially active and conspicuous.  Vistas are broader, trails are firmer and those pesky insects have either died off or escaped to their wintering sites.  Birders know that many avian species can only be observed during the colder months and that rare visitors (especially irruptive species) are most often encountered at this time of year.

Finally, for those of us who treasure solitude, the winter season offers abandoned trails, uncluttered parks and the opportunity to explore nature's ecosystems in quiet mode. We may have evolved in the Tropics but our adventurous spirit has taken us across the globe and into winter's realm.

Wednesday, January 10, 2018

Yellow-billed Loon visits Littleton

A yellow-billed loon is visiting South Platte Reservoir, in Littleton, attracting flocks of Front Range birders to the site.  Present for a week or so, the loon may hang around as long as it finds enough food or until spring arrives.

Natives of Arctic Canada and Alaska, yellow-billed loons are the largest members of their family.  After breeding on tundra lakes during the endless sunshine of the Arctic summer, they head for coastal waters of southern Alaska and British Columbia for the winter months.  There they ride out the season on coastal bays, diving for fish.

Some may winter farther down the Pacific Coast but yellow-billed loons rarely head for inland lakes.  Our current visitor is thus creating a great deal of excitement in Colorado and reminding us all that you never know what you'll find until you get out there and look!

Monday, January 8, 2018

Killers on the Highway

Heading back to Colorado, I drove from Columbia, Missouri, to Hays, Kansas, today.  The weather on the Great Plains was sunny and mild, a welcome change from the recent Arctic plunge.  Raptors seemed to appreciate the change as well, perching along the highway or soaring overhead.

Though I did not make an official count, I'm sure I saw more than 200 red-tailed hawks on today's journey, at least 20 of which were in pairs.  American kestrels were also common, though not as numerous, and several red-shouldered hawks were observed in Missouri.  Two bald eagles flew across the highway, one in west-central Missouri and the other above the Kansas River in Kansas City.  Six northern harriers (all male) were observed on the trip and a lone rough-legged hawk was encountered near Russell, Kansas (many more rough-legs will likely be seen tomorrow as I cross the High Plains of western Kansas and eastern Colorado).

Joining these hunters was a mystery raptor in eastern Kansas.  A light-colored falcon with a distinct yellow bill swooped across the Interstate and curved back to the east before I could get a close look.  My initial impression was that this bird was a gyrfalcon, an Arctic species that may be observed across the northern Plains in winter but would be extremely rare as far south as Kansas.  The other (and more likely) possibility is that it was a light-colored prairie falcon.

Sunday, January 7, 2018

Evolution of Male Baldness

While male baldness has become stylish in recent decades, it has long been a source of anxiety in men, especially when it develops at a young age.  Just look at the trouble our President goes to in order to hide his balding pate.

The evolutionary benefit (if any) of male pattern baldness has long been the subject of debate.  It is known that genetics play a major role; an X-linked gene (inherited from the mother) is clearly involved in many cases while inheritance from the father also occurs but is less well understood.  We also know that male baldness occurs in chimps, a species that shares more than 98% of our genes.

The question remains, however, why these genes have been retained throughout human history.  Some have suggested that male baldness is just the next stage in our evolution as the "naked ape" while others surmise that balding is sexually selected as a sign of maturity.  Since we evolved in the tropics, it is possible that hair loss from the scalp (which is highly vascular) may have been beneficial in the dissipation of heat during strenuous hunting activity.  In the end, baldness may just be genetically linked to other metabolic traits (e.g. higher testosterone levels) that somehow benefit survival. 

Saturday, January 6, 2018

Trump and our Natural Heritage

Many Americans could offer a variety of reasons why President Trump should be removed from office but those of us who care about the health and welfare of Earth's natural ecosystems are especially alarmed by the actions of his Administration.  Slashing environmental regulations and ridiculing the science of climate change, they have favored economic development at every turn.

Having opened up National Monuments and Wilderness Areas for oil and mineral extraction, the Trump Administration has now indicated their intention to permit offshore oil drilling along all coastal areas of the U.S., including the Arctic Ocean.  Seemingly blind to the potential complications of such a policy (do they not recall the Deepwater Horizon disaster?), these right-wing zealots are proceeding with reckless disregard for our natural environment.

No doubt, their conservative political convictions are tied to religious beliefs that grant them dominion over the planet (in Trump's case, it's just pure narcissism).  Were they to accept the fact that we humans are part of nature, just another species on the vast tree of life, they would surely be less sanguine about their policies.  Our natural heritage is at risk and a change in national leadership cannot come soon enough. 

Wednesday, January 3, 2018

The Ancestry Craze

One can hardly watch television, surf the internet or peruse a magazine without encountering ads for companies that want to research your ancestry.  Since DNA analysis has become less expensive and more widely available, it is only natural that entrepreneurs have found ways to make money with that technology.

While most humans are interested in their "recent" ancestry (i.e. where their great grandparents were born), relatively few of us care to know that we are, for example, 20% Somalian, 30% Irish, 15% Russian and 35% Polynesian.  We understand that human cultures have been mixing (sexually) for thousands of years and that we are all genetic mosaics.  On the other hand, one can hope that such data might put a lid on racial supremacy and zealous nationalism.

At no charge, I offer the following ancestral revelations.  Wherever we may have been born, we are all Africans from the perspective of our genetic heritage; indeed, we share more than 98% of our genome with chimpanzees from which our ancestors diverged 7 million years ago.  In addition, those humans of European or West Asian descent are 5% Neandertal (genetically speaking) while those of East Asian or Australian descent harbor Denisovan genes (4-5% of their genome); anthropologists also suspect that early humans interbred with Homo erectus, the immediate predecessor of Homo sapiens.  See also Human Hybridism.

Tuesday, January 2, 2018

North to a Frozen Landscape

Leaving Longboat Key early on New Years Day, we were enveloped in relatively cool pre-dawn air (61 degrees F) as we headed north.  By the time we reached Tampa, light mist was coating the windshield and bands of showers continued to fall throughout northern Florida; this precipitation marked the leading edge of the cold front that had placed most of the central and eastern U.S. in a deep freeze.  Sunshine broke through the clouds as we crossed into southern Georgia but the temperature was a humid 39 degrees F.  The cooling progressed as we travelled northward through Georgia and, when we reached Chattanooga for our overnight stay, it was 12 degrees in the Tennessee River Valley. 

This morning, we crossed the Cumberland Plateau before dawn, the winter landscape lit by a bright super-moon, and we were greeted by a 5 degree air mass in the Cumberland River Valley at Nashville.  Neither the Tennessee nor the Cumberland River had ice floes but, farther north, all lakes, ponds and small rivers were frozen over and a dusting of snow coated most of the farmlands; ice floes clogged both the Mississippi and Missouri Rivers at St. Louis.

We finally reached Columbia by mid afternoon where, despite the bright sunshine, it was 15 degrees (having climbed from an overnight low of minus one).  As the massive dome of frigid air moves eastward, we'll slowly warm up here in the Heartland; above freezing temperatures are expected by this weekend.  After almost two weeks in the warm, Subtropics, it may take us that long to adjust.

Monday, January 1, 2018

Aesthetic Evolution: Not Convinced

Since I have been a birder for more than forty years and have long had an interest in natural history, my son gave me a copy of The Evolution of Beauty, How Darwin's Forgotten Theory of Mate Choice Shapes the Animal World--and Us, by Richard O. Prum.  An ornithologist himself, Prum devotes most of his book to the discussion of exotic mating rituals in birds and the last couple chapters to the evolution of human sexual behavior.  In my opinion, the ties between the two are a bit of a stretch.

Mr. Prum points out that Darwin's first book, On the Origin of Species, is renowned for presenting his theory of natural selection but that his second book, The Descent of Man, makes a case for the role of sexual selection in evolution, a theory that has received a cool reception among most evolutionary biologists.  Prum's book, by his own account, is an effort to defend and expand upon Darwin's theory that sexual selection (i.e. mate choice) has long played a significant role in the evolution of animals.  While his data is very thorough and interesting, I fall into the category of what Prum calls neo-Wallacians (those who are inclined to accept the unvarnished adaptive evolution model proposed by Alfred Russell Wallace, Darwin's colleague).

First of all, I think the phrase "Evolution of Beauty" is misleading and actually works against his argument.  While most of us accept the fact that sexual selection has played a major role in the evolution of intelligent hominids (i.e. humans), physical appearance is but one of many factors in the selection of a mate (a point that Mr. Prum thoroughly discusses himself).  To suggest that female birds choose mates based solely on the beauty and complexity of the males' mating displays is to imply that they are capable of subjective choice and that other factors are not involved.  In the end, the concept of aesthetic evolution seems to simplify a very complex process that, most naturalists believe, is devoted solely to the propagation of one's genome.  Nevertheless, I recommend that you read Prum's book and decide for yourself.