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Showing posts from January, 2008

Belugas

Belugas are small, white, toothed whales that inhabit the Arctic and sub-Arctic waters of North America and Siberia. Gregarious, they prefer shallow, coastal regions and are usually found in pods of 10-25 individuals; at times (especially during migrations) they congregate by the hundreds or thousands in favored bays or estuaries. Though they can submerge for twenty minutes and dive to 2000 feet, belugas generally feed in shallow waters, consuming a variety of fish, crustaceans, squid and octopi; small pods have even been known to follow migrating salmon for hundreds of miles up large, Arctic Rivers. Closely related to narwhals, they often travel and feed with those aquatic unicorns.

Since they hunt along and beneath the Arctic pack ice, belugas are adept at finding cracks or open "polynyas" through which they surface to breath; such behavior may have led to their loss of a dorsal fin (through natural selection) which would impair their maneuverability among the pack ice. Bre…

From Spring to Winter

Today dawned like an April morning, with a clear sky, balmy air and a hint of moisture on the streets; it was 54 degrees F. By mid morning, clouds began to build, the wind shifted to the north and the temper-ature began to plunge. At noon, under gray skies, it was 32 in Columbia; at the same time, it was 19 in Kansas City and 68 in St. Louis.

The dramatic change was, of course, due to the passage of an Arctic cold front, ushered in by powerful, northwest winds. The center of the storm, moving across the northern Great Lakes region, is a "tightly wound" zone of low pressure; producing blizzard conditions in the Upper Midwest, the storm will also trigger severe thunder-storms ahead of its trailing cold front, from the Gulf Coast to the Ohio Valley. Here in central Missouri, a mix of "backside" snow and sleet is pelting the window at 2 PM and the temperature is down to 21 F; coupled with strong, northwest winds, the wind-chill sits at 7 degrees.

Such potent winter storm…

Country Sparrows

Of the common winter sparrows, two are not often found in urban or residential areas. Rather, they prefer more open habitat and those who want to see them will need to venture into the country.

The American tree sparrow is an attractive bird with a red cap, gray face and unstreaked chest with a central spot. This visitor is best found in wooded meadows or in border zones where woods and grassland meet. Often seen in sizable flocks, tree sparrows feed on the ground with juncos and other sparrows. They breed across northern Canada and winter throughout central latitudes of North America.

The white-crowned sparrow also favors open country and is best found in hedgerows or thickets along fields and pastures. Easily identified by his striped crown (black and white) and unstreaked, gray underparts, this sparrow may turn up at feeders during the spring migration (late March through April) but usually winters in farm country, from the mid Atlantic to the Southwest. White-crowned sparrows …

Smoky Hills Wind Farm

On my last few trips between our Missouri and Colorado homes, I have watched a large wind farm sprout from a broad ridge in central Kansas, just north of I-70. Located along the Ellsworth-Lincoln County line, about 25 miles west of Salina, the first phase of the Smoky Hills Wind Farm project is nearing completion. This phase will cover 12,000 acres and include 56 three-blade turbins, producing more than 100 megawatts of energy; that will provide enough electricity for 30,000 homes and offset 300,000 tons of CO2 production.

Phase two, to be completed by November, will cover another 12,000 acres and produce an additional 149 megawatts of energy, offsetting 450,000 tons of carbon dioxide. As one might expect, the project has been controversial, the benefits of clean energy production weighed against the visual pollution on the prairie landscape (the gleaming white turbins are 260 feet tall). Siding with the energy companies, the Sierra Club has supported the wind farm's development, n…

Late Day Visitors

Yesterday, as the sun was poised to drop behind the Front Range, a flock of sixty or more cedar waxwings descended on our farm. These nomads of the bird world typically move about in large flocks for most of the year, seeking berry-producing shrubs and trees. Our visitors settled in a few bare deciduous trees adjacent to a row of junipers.

Unlike many flocking species, waxwings are remarkably calm and cooperative; naturally gregarious, they are very tolerant of one another, rarely bickering or competing for food. Part of the flock will usually perch patiently in nearby trees while the rest of the group drops into the berry patch to feed. Also fond of flower petals (especially fruit blossoms), these attractive and amiable birds often pass a berry or petal down the line until one decides to eat it.

True to their nomadic lifestyle, waxwings may spend a day or two in the neighborhood and then move on. Adventurous, cooperative and friendly, they possess traits that we humans would do we…

Four Juncos

Dark-eyed juncos are small, hardy, attractive birds that winter throughout most of the U.S. Often called "snow birds," they are represented by four races which were once considered to be distinct species; the races themselves demonstrate regional variation in their plumage. All races are ground feeders (often foraging with sparrows) and are easily identified by their outer white tail margins when they fly off.

Slate-gray juncos are the common race of the eastern U.S., breeding in coniferous forests of Canada and the Appalachians. Oregon juncos are the most common race along the West Coast and gray-headed juncos represent the species in the foothills, mesas and mountain forests of the Rocky Mountains and Colorado Plateau. Finally, the white-winged junco, more restricted in range than the others, breeds in the Black Hills of South Dakota and winters through the southern Rockies.

All four races winter along the Colorado Front Range, three of which are regular visitors to our …

Winter on the Farm

Our small farm in Littleton, Colorado, sits on the west wall of the South Platte Valley. Each morning, we are treated to a spectacular sunrise and, during the winter months, to squadrons of Canada geese as they leave the river to feed on regional grasslands.

On the farm itself, only the junipers, spruce and pinyon pines add color to the brown fields and barren woods. We often spot our resident fox early or late in the day, making her rounds of the woodpiles and pastures in search of mice. Though common birds such as robins, crows, magpies, chickadees and house finches dominate the avian population, we usually have a Townsend solitaire or two during the colder months, down from the mountains to feast on our juniper berries. A red-tailed hawk, often harassed by the crows, winters on the property and sharp-shinned hawks are frequent visitors. Other than the fox and her quarry of mice and voles, our resident mammals are limited to raccoons, fox squirrels and skunks; on occasion, a coyote t…

Apishapa Canyon

Most visitors to Colorado head for the mountains or western canyonlands, often deriding the State's eastern plains as a dull, flat extension of Kansas. But naturalists know that there are many interesting areas across these High Plains, including two National Grasslands, the Palmer Divide, a number of large lakes, the South Platte and Arkansas Valleys and some unexpected topography; among the latter is Apishapa Canyon, in southern Colorado.

Rising on the east flank of the Culebra Range and on the south side of the Spanish Peaks, the Apishapa River flows eastward and then northeastward, joining the Arkansas east of Fowler.
Along the way, this stream and its tributaries have cut a deep, scenic canyon in the semiarid plains, a natural oasis for a wide variety of wildlife. Herds of pronghorn graze the adjacent grasslands while mule deer and bighorn sheep inhabit the rugged walls of the canyon; predators include coyotes, bobcats, swift fox and the occasional mountain lion. Resident birds…

Weather Wall

When polar air drops into the Northern Plains it is often rather shallow and its movement is frequently not governed by a fast-moving front. Under such conditions, the cold, dense air fans out across the Heartland, seeking lower elevations as water does on a tilted surface. As a result, this air mass tends to move primarily to the south and east, guided by the terrain of the region; the more frigid (more dense) air moves into the river valleys and lake basins.

If the layer of cold air is thick enough, some will move uphill (westward) across the High Plains, eventually reaching the Front Range of the Rockies. Like a giant dam, this lofty ridge prevents the polar air from spilling into the Intermountain West, producing remarkable weather variance on either side of the mountains. Furthermore, as the cold air "climbs" toward the Continental Divide, it cools further and drops its meager precipitation as light snow.

After a mild afternoon yesterday, a subtle wind shift (from the…

Winter Oasis

By mid winter, most lakes and ponds along the Colorado Front Range are frozen over and the South Platte River becomes a vital source of open water. Flowing northeastward through Metro Denver, the River attracts a wide variety of wildlife, a winding oasis in a dry, frozen landscape.

This morning, a walk along the South Platte offered a study in waterfowl. Hundreds of Canada geese rested in its shallows, soon to depart for a day of grazing on fields and grasslands. Joining the Canadas were mixed flocks of mallards, gadwall, common mergansers, common goldeneyes, buffleheads, ring-necked ducks, shovelers and hooded mergansers. A few coot, pied-billed grebes and great blue herons also fed near the banks.

The highlight of the morning was an adult bald eagle that moved ahead of us along the River. Perching in large cottonwoods that tower above the floodplain, the eagle would wait until we were within ten yards and then fly downstream for a quarter mile or so, repeating this pattern severa…

Day of the Raptors

On our trip back to Colorado today, the sun blazed in the southern sky but had little effect on the cold, Arctic air that enveloped the Great Plains. And while a blanket of snow softened the gray and brown landscape, there was no denying that this is the lean season, the season of survival.

As is usually the case in winter, raptors dominated the wildlife scene. We saw a hundred or more red-tailed hawks in Missouri and eastern Kansas, perched in barren trees along the highway; American kestrels were also common, hunting from power lines or hovering above the grassy medians. A lone shrike perched on a sapling in the Flint Hills of Kansas and a pair of bald eagles soared above the Smoky Hill Valley at Junction City.

Further west, where trees are limited to towns and stream channels, northern harriers were the primary raptors, flapping low above the crop fields in search of prey. Near Oakley, Kansas, several rough-legged hawks hunted on the grasslands, easily identified by their black t…

The Paleozoic Center

From the Appalachian Plateau to the Central Plains and from the Great Lakes to the north edge of the Gulf Coastal Plain, almost all of the exposed bedrock was deposited in the Paleozoic Era. This second major division of geologic history, 600 to 225 million years ago, stretches from the appearance of shelled marine life to the rise of mammal-like reptiles.

Though older, Precambrian rocks underlie these Paleozoic sediments, they are exposed only in the northernmost region of the Great Lakes (where the glaciers scraped off younger rocks) and in southeast Missouri, where an uplift of this ancient basement has been carved into the St. Francois Mountains. Throughout the Paleozoic Center of North America, younger rocks are primarily limited to poorly compacted sands, gravels and loess from the Pleistocene Epoch; these recent deposits are found along the major river channels, across the Coastal Plain and atop the Paleozoic bedrock in the northern Midwest, where a thick layer of glacial till…

The Fear of Science

This week, the Pope cancelled his visit to an Italian University due to the protests of that institution's professors and students. Their reason: in 1990, 21 years after man landed on the moon, the Pope, then a Cardinal, defended the Church's persecution of Galileo back in the 1600s. His defense: at the time, Galileo's contention that the planets revolved around the sun was unproven and counter to "rational belief."

Religion has always been threatened by scientific knowledge and has a long history of attempting to derail its progress. Even today, almost 400 years after Galileo, we have a State that wants to eliminate the teaching of evolution and a presidential candidate who believes in the literal interpretation of Scripture. The support for such positions comes primarily from a scientifically uneducated populace who, ingrained with strong religious beliefs, don't want academicians disrupting their simplistic view of the world (and their hope for immortality)…

Tumbling Highs

Three domes of high pressure will dominate the U.S. weather map over the next few days. The first, over the Great Basin, will keep the Interior West clear, cold and dry but will likely produce strong Santa Ana winds in Southern California. The second dome, now centered over the mid Atlantic States is helping to produce heavy rains along the Gulf Coast; as the high drifts to the northeast, this rain will follow, bringing much needed precipitation to Alabama, Georgia and the Carolinas. Unfortunately, cold air, injected southward by the high pressure, will likely produce significant icing in north Georgia and western North Carolina.

The third and final high pressure dome, now lurking in western Canada, will drop into the Northern Plains and Upper Midwest, bringing frigid, Arctic air and producing lake-effect snows.
The movement and interaction of these domes is governed by the jet stream, which curves between them like an engine belt between rotors; dips in the jet allow domes to drop f…

The Uniformity of Life

If you accept the Big Bang theory, the universal laws of physics and the uniformity of chemical processes, then it is reasonable to conclude that evolutionary patterns have been very similar throughout the Universe. There is no scientific reason to doubt the existence of life on millions (if not billions) of other planets and, based on the preceding theory, these life forms likely developed under similar circumstances and evolved in accordance with the universal laws of nature.

On the other hand, the progression of evolution has likely varied tremendously. In many cases, the planet's chemistry may have prevented development beyond the bacterial stage. On other planets, catastrophic events may have caused major setbacks in the evolutionary process, placing them well behind our time frame; or perhaps they are stuck in the Mesozoic, their dinosaurs never succumbing to an asteroid and their mammals never evolving beyond the small, rodent stage. Then again, life surely developed on some…

The Extreme Desert

A desert is generally defined as an area that averages less than ten inches of precipitation per year. None is more dry than the Atacama Desert of Northern Chile, parts of which have never received measurable precipitation (at least since man has been around to observe).

Covering 70,000 square miles, between the Pacific Coast and the Andes Mountain Range, the Atacama encompasses a variety of terrain, covered mostly by salt flats, sand dunes and lava flows. Any precipitation arriving from the east is cut off by the high wall of the Andes and what little drifts in from the ocean is wrung out by the Coastal Mountains; the inflow of moisture from the Pacific is further blocked by the Humboldt Current, an upwelling of cold sea water that flows northward along the west coast of South America. Some coastal regions of the Atacama receive minimal but regular moisture from a dense marine fog, which condenses on the few cacti and desert shrubs that manage to survive there. At higher, foothill ele…

Truculence in Blue

Winter is the season of the jay. Though birdsong is generally subdued, the harsh call of the blue jay rings through the neighbor-hood, announcing his intention to remain in charge. And while his plumage is attractive, especially against a background of snow, this avian general is despised by some backyard birders; chasing smaller birds from the feeder, he indulges himself at will, ingesting more than his share of sunflower seed.

Omnivorous and aggressive, blue jays feed on a variety of seeds, fruits, acorns and insects; they are also known to feast on the eggs and nestlings of other birds, hardly endearing them to the casual naturalist. And, despite their fierce independence, jays frequently cooperate to harass larger predators, noisily shrieking at hawks, owls or domestic cats until they leave their territory.

While we may not be fond of their personality and behavior, blue jays, like all native species of wildlife, play an important role in the natural ecosystem. Among other beneficia…

Aransas

By 1941, only 15 wild whooping cranes remained in North America. Since that time, thanks to habitat protection, pollution control, public education and a captive breeding program, the wild flock has grown to more than 230 birds, which summer and breed at Wood Buffalo National Park, in Canada's Northwest Territories. Migrating 2500 miles across the Great Plains, almost all of these majestic birds winter at the Aransas National Wildlife Refuge, on the Texas Gulf Coast.

Established in 1937, this Refuge consists of six units, totalling more than 115,000 acres. The main section lies along San Antonio Bay, northeast of Rockport, and is a mosaic of tidal marshes, grasslands, sloughs, redbay thickets and woodlands; stands of live oak dominate the latter. In addition to the whooping cranes, winter visitors have a chance to see American alligators, armadillos, javelina, ringtails, swamp rabbits and bobcats. Birding can be spectacular at Aransas; highlights include American white pelica…

The Grassland Owl

Breeding throughout Canada and across the northern U.S., short-eared owls are common winter visitors in the Heartland. These mid-sized owls favor grasslands, abandoned farm fields and open marsh, where they hunt for mice and voles. Staying out of the woods and close to the ground, they usually roost on fence posts, low structures or muskrat mounds.

Up close, the short-eared owl is identified by his golden-brown, heavily streaked plumage, his long wings with black wrist marks and his yellow eyes, each set in a patch of black; his small ear tufts are often not evident. Usually viewed from a distance, this open country owl is recognized by his halting flight and tendency to hover; he is often mistaken for a female northern harrier, which has similar plumage, favors the same habitat and has a similar hunting style.

One of the few owls active during the day, short-ears are best observed in the early morning and late afternoon, when they patrol for mice. Somewhat gregarious during the win…

Hominids and the Pliocene

The Pliocene Epoch, a relatively short period in geologic history (10-2 million years ago), covers a very important phase in early human evolution. Early in the Pliocene, as the Rio Grande Rift was developing, the Tetons were rising and the Galapagos Islands were forming, gorillas diverged from the common ancestor of chimps and humans.

By the middle of the Epoch, coincident with the development of the San Francisco Volcanic Field in northern Arizona and the docking of the Salinia Terrain to form Southern California, chimps diverged from the human ancestral line. Then, about 4.5 million years ago, as Kauai's formation gave way to Oahu's development and the Baja of California began to rift from the Mexican mainland, Australopithecus appeared in East Africa; the males of this earliest known hominid weighed 100 lbs., twice the size of females.

Near the end of the Pliocene, as the Sierra Batholith was rising, Panama was drifting in to connect the Americas and Easter Island was develo…

Ice and Human Dispersal

Most anthropologists believe that modern man evolved in East Africa, about 125,000 years ago; this coincides with the last, warm interglacial period of the Pleistocene and precedes the Wisconsin Glaciation. Likely confined to Africa for 50,000 years or more, humans began to spread beyond their home Continent as the climate cooled, precipitation increased and the vast Sahara Desert began to retreat. The gradual formation of the Wisconsin Ice Sheets, beginning about 75,000 years ago, tied up an increasing supply of Earth's water and sea levels started to fall; at the peak of this glacial period, about 25,000 years ago, sea level was 400 feet lower than it is today.

As sea level fell, the exposed Continental margins spread outward, archipelagos became long peninsulas and offshore islands were attached to the mainland; eventually, the broad Bering land bridge connected Asia with North America. DNA studies suggest that man first spread along the southern edge of Asia, reaching Southeast…

The Western Appalachians

The Southern Appalachians, which stretch from New York to Alabama, formed as the North American and African Plates collided, about 250 million years ago. Folding, faulting and uplift along this swath created a broad chain of highlands, characterized today (west to east) by the Appalachian Plateau, the Ridge and Valley Province and the Smoky-Blue Ridge Mountains.

The above collision occurred during the assembly of Pangea, the Permian mega-continent that formed as the Continental Plates merged. During this process, pressure was also exerted along the southern edge of the North American Plate, extending the Appalachian Orogeny westward from what is now northern Alabama. At that time, much of Mississippi, eastern Arkansas and southeastern Missouri did not exist; the Ozark Plateau was a westward extension of the Appalachian Plateau and the Ouachita Mountains of Arkansas-Oklahoma were continuous with the southern end of the folded Appalachian chain. Then, as Pangea broke apart, the Gulf …

January Thaw

High pressure to our east and a deep low pressure system to our west have combined to produce strong, southerly winds across the Heart-land over the past two days. Warm, Gulf air has been streaming northward, bringing record high temperatures to the Central Plains and Great Lakes region. Yesterday, we topped out at 72 degrees F in Columbia and this morning's low was 59!

Such warm winter episodes may trigger spring growth in bulb plants, bring chipmunks from their dens and rouse a host of insects from their months of suspended animation. But birds and mammals will not be fooled by this respite from the cold; their breeding behavior and migratory urges are tied to the light cycle, not to the daily temperature. And, while they no doubt enjoy the pleasant weather as much as we do, their activities, vital to their survival, go on as usual.

Today, the cold front of the recent Pacific Coast storm is bearing down on our warm, moist air mass and should trigger thunderstorms by late afternoon…

Wintering Woolly Bears

Most insects of the Temperate Zone winter as eggs or pupae, providing nutritious snacks for mice and birds. Some, including ladybird beetles and honey bees, overwinter as adults, massing in sheltered areas to conserve heat. Though aquatic larvae are common, relatively few terrestrial insects overwinter in the larval form.

One of the more common and well known wintering caterpillars is the woolly bear, the larvae of Isabella tiger moths. These fuzzy, red-brown and black caterpillars have long been rumored to have weather-forecasting skills, the thickness or color of their coat indicating the severity of the coming winter. While this is purely folklore, woolly bears are often encountered during the winter months, seemingly out of place in the snowy landscape; in fact, my wife and I saw one yesterday, crawling across a muddy trail.

Woolly bear caterpillars spend the winter in sheltered areas, beneath log piles, leaf litter or dense vegetation. Periods of warm weather or a disruption of the…

Pacific Wind Machine

Yesterday afternoon, a massive winter storm was centered off the coast of Washington State; its central pressure was equivalent to a Category 3 Hurricane and its counterclockwise wind field extended as far south as central California. Energized by the jet stream, the storm raked the entire Pacific Coast with high winds and heavy precipitation.

Waves along the Northwest Coast rose as high as 40 feet and winds of 60-80 miles per hour swept across Washington, Oregon and Northern California. Coastal mountains were drenched by a foot of rain and snow levels were dropping across the Sierra Nevada. The worst of the storm was reserved for the central Sierra Mountains, where winds over 160 miles per hour scoured the summits and up to 12 feet of snow was expected.

While the center of the storm has drifted into southwest Canada this morning, the jet stream trough is diving along the Pacific Coast and impulses of low pressure will move along its track, bringing more precipitation to the Northwes…

Colorado Lynx

Apparently extirpated from the State by 1973, lynx would not be seen in Colorado for more than 25 years. Then, in 1999, the Division of Wildlife began a reintroduction program, relocating lynx from their homes in western Canada to the rugged terrain of the San Juan Mountains.

Initially plagued by setbacks, this ambitious program finally achieved success in 2003 when the first litter was produced by transplanted adults; an even more significant milestone was reached in 2006, when a female, born in Colorado, gave birth to a litter of kits. As of 2007, more than 215 lynx had been reintroduced to the State and over 115 births had been documented; however, losses to predation, disease, malnutrition and accidents have kept the current Colorado population near 200 individuals.

Lynx are medium-sized felines, distinguished from the more common bobcat by their long legs, black ear tufts and large, furred paws. Adults, which average 20 lbs., are secretive, solitary hunters, often roaming widely in…

Missouri's Great Lakes

Three large reservoirs span the upper watershed of the Osage River in southwest Missouri. These lakes (Truman, Pomme de Terre and Stockton) are deep enough that they remain partly open throughout the winter, attracting a wide variety of diving ducks and other fish-eating birds.

Rafts of scaup, ring-necks and redheads appear on the open waters, joined by smaller flocks of buffleheads, common mergansers and common goldeneyes. Bald eagles and a variety of gulls gather along the margins of the ice while peregrine falcons patrol the lake from nearby trees.
These Missouri lakes also attract a number of rare visitors, which may arrive anytime from November through March; these include Pacific, yellow-billed and red-throated loons, white-winged, surf and black scoters and pomarine or parasitic jaegers.

All three reservoirs are west of U.S. 65 and the deeper waters near the dams tend to be most productive. Truman Lake is just west of Warsaw, Pomme de Terre Lake is south of Hermitage (via Misso…

Deep Freeze

Even most of us who prefer winter to the hot, humid summer are not especially fond of temperatures in the single digits. Arctic air has now settled over the Midwest and it was 7 degrees F as I walked to work this morning. But, with little wind, dry air and both Venus and a crescent moon hanging in the southeastern sky, it was a pleasant, invigorating stroll.

While humans are not naturally equipped for cold weather, most people who despise winter do not dress properly to enjoy it and spend too much time staring at thermometers or listening to dire weather forecasts. Those who venture out (with warm, layered clothing and common sense precautions) are rewarded with solitude, broad vistas and active wildlife. Besides, a taste of the Arctic deepens our appreciation for those plants, animals and humans that live and thrive under such conditions.

Our current deep freeze should resolve quickly as the frigid air mass moves off to the east and southwesterly winds begin to moderate our tempera…

Resolutions for Wildlife

As Americans across the country make their New Year's commitments to lose weight, give up tobacco or stop drinking certain beverages, I suggest that we include a few resolutions to benefit the wild creatures that share this planet:

First, let's resolve to leave the remaining wilderness intact. We should be able to manage living on the land that we have already plowed, cemented or otherwise "developed." In the meantime, we can begin protecting and restoring those open spaces that are vital to migrant and resident wildlife.

Second, let's commit ourselves to minimize our impact on natural ecosystems by reducing toxic emissions, eliminating pollution, recycling what we use and getting maximum longevity from the products that we consume.

Third, let's support efforts to control the human population. If we are unable to do this, all other conservation programs will be in vain.

Finally, let's provide financial and/or active support for the local, regional and inte…