Entering Eagle Bluffs Conservation Area this morning, the windows down on my pickup, it looked like January but felt like April. The brown vegetation and barren trees evoked an image of winter but the mild air, scented with the fragrance of moist soil, spoke of early spring. A rosy dawn backlit the hills to the east, augmenting the feel of an April morning.
Mallards were abundant on the ponds and wet fields, joined by sizable flocks of coot, gadwall, pied-billed grebes and Canada geese; small flocks of shovelers, lesser scaup and ring-necked ducks also graced the scene. As is typical for mid winter, ring-billed gulls swirled above the wetlands, northern harriers strafed the crop fields, red-tailed hawks patrolled the grasslands and an immature bald eagle circled overhead, spooking the ducks. Great blue herons stalked the shallows, sharp-shinned hawks darted through the woodlands and, surprisingly, a quartet of American white pelicans gathered along a marshy shoreline, satisfied to stay up north for this mild winter season.
Parking in a remote lot, I got out to enjoy the spring-like conditions; since the waterfowl hunters have departed and the spring birding crowd has not yet arrived, I was treated to the peaceful solitude of the winter season, minus the blowing snow and frigid air. Though a freight train rumbled west of the Missouri, all other sounds were natural, including the raucous call of crows, the muted chatter of waterfowl, the rustling of sparrows in the dry grass and the drumming of woodpeckers in the riverside forest. A special treat was the distant howl of a coyote, yet another sign that the season of renewal will soon invade the floodplain; I could almost see the purple haze of henbit on the barren fields.
Tuesday, January 31, 2012
Monday, January 30, 2012
Dividing Humanity
We have long become familiar with Christian colleges, Christian bookstores and, more recently, Christian dating services. Now, as advertised on TV last evening, there is a Christian insurance company that, according to their ad, only welcomes nonsmoking Christians. One wonders if they are willing to insure morbidly obese Christians; how about Christians who abuse alcohol or use injectable street drugs? Why not take a chance with Jewish tri-atheletes or Muslim vegetarians?
While they publicly espouse tolerance, religious organizations, zealously self-righteous, are among the most divisive forces in human society. If businesses can restrict access to members of one religion, why not discriminate based on race, ethnicity, sexual orientation, gender or socioeconomic status?
Perhaps this company is just testing the waters, trying to determine how sensitive America might be to such policies. Perhaps they are blind to the sectarian strife that pervades many other nations across this globe. Or perhaps they are just simple-minded zealots who place their narrow-minded views above any concern for the welfare of human society. Regardless of their motivation, their message of intolerance must be challenged if our country is to uphold the freedoms that we so vigorously defend.
While they publicly espouse tolerance, religious organizations, zealously self-righteous, are among the most divisive forces in human society. If businesses can restrict access to members of one religion, why not discriminate based on race, ethnicity, sexual orientation, gender or socioeconomic status?
Perhaps this company is just testing the waters, trying to determine how sensitive America might be to such policies. Perhaps they are blind to the sectarian strife that pervades many other nations across this globe. Or perhaps they are just simple-minded zealots who place their narrow-minded views above any concern for the welfare of human society. Regardless of their motivation, their message of intolerance must be challenged if our country is to uphold the freedoms that we so vigorously defend.
Sunday, January 29, 2012
White-throat Serenade
Every winter evening, as the sun begins to set behind a woodland to our west, a flock of white-throated sparrows returns to our backyard feeder. Filtering in as pairs or small groups, they scour the ground for fallen seed; often joined by northern cardinals, they are polite birds, not inclined to squabble over the handouts.
After a period of silence through early winter, they have begun to sing during the past week, a response to the lengthening daylight. Their distinctive, homesick tune will increase in intensity over the next several months and, by mid April, they will depart for Canada to breed in the vast Northwoods.
Accustomed to chilly, gray conditions, white-throats are also among the first birds to become active on winter mornings and their song is a welcome serenade on my walk to work. More importantly, it offers reassurance that winter is loosing its grip and that the mild, fragrant days of early spring are on the horizon.
After a period of silence through early winter, they have begun to sing during the past week, a response to the lengthening daylight. Their distinctive, homesick tune will increase in intensity over the next several months and, by mid April, they will depart for Canada to breed in the vast Northwoods.
Accustomed to chilly, gray conditions, white-throats are also among the first birds to become active on winter mornings and their song is a welcome serenade on my walk to work. More importantly, it offers reassurance that winter is loosing its grip and that the mild, fragrant days of early spring are on the horizon.
Saturday, January 28, 2012
The Purpose of Life
Throughout human history, man has pondered the purpose and meaning of life. Endowed with a large brain, we have convinced ourselves that the ecosystems of planet Earth were created for our benefit and human cultures have imagined a wide range of gods that facilitate and govern that process. The fact that life evolved almost 3.6 billion years before our own species appeared is ignored or rejected by most religious persons; after all, they believe that this earth-bound life is preparation for a more significant, eternal existence.
If we strip away the cloud of human mysticism, we find that life has the single purpose of sustaining itself and has "learned" that diversification is the best means to accomplish that goal. In the words of that thoughtful scientist in the film Jurassic Park, "life will find a way."
Unfortunately, the mysticism of human society often impedes the purpose of life, as religious and sectarian wars decimate populations and as the culture of human superiority encourages the exploitation of our natural resources. If we truly support the purpose of life, we humans need to end our futile conflicts, devote ourselves to protecting the natural diversity of this planet and ensure that our own unbridled population growth does not threaten the sustainability of Earth's ecosystems.
If we strip away the cloud of human mysticism, we find that life has the single purpose of sustaining itself and has "learned" that diversification is the best means to accomplish that goal. In the words of that thoughtful scientist in the film Jurassic Park, "life will find a way."
Unfortunately, the mysticism of human society often impedes the purpose of life, as religious and sectarian wars decimate populations and as the culture of human superiority encourages the exploitation of our natural resources. If we truly support the purpose of life, we humans need to end our futile conflicts, devote ourselves to protecting the natural diversity of this planet and ensure that our own unbridled population growth does not threaten the sustainability of Earth's ecosystems.
Friday, January 27, 2012
American Gators
Crocodilians, now represented by crocodiles, alligators and caimans, split from other reptiles and early dinosaurs back in the Triassic Period, some 200 million years ago. Modern alligators are limited to two species: the American alligator and its smaller cousin in southern China; our gator, the largest reptile in North America, inhabits the Southeast Coastal Plain, from North Carolina to Texas.
Up to 15 feet long and weighing as much as 800 pounds, adult males bellow in mid spring to attract a mate. Once impregnated, the female builds a nest mound of rotting vegetation and deposits 20-50 eggs before covering them with more vegetation. Staying close by until they hatch (usually in August), the mother protects her young, digging them out and carrying them to open water in her mouth; she will continue to watch over her offspring for their first year of life. Those eggs that incubate at temperatures above 90 degrees F produce males while those below 86 degrees produce females; nest temperatures in between these parameters yield a mix of genders.
Young alligators may fall victim to a variety of predators, including snakes, large fish, snapping turtles, raccoons, bobcats, bald eagles and other alligators; once fully grown, however, American gators are threatened only by human hunters and habitat loss and may live 50 years or more in the wild. Nearly driven to extinction by overhunting and swamp drainage during the first half of the 20th Century, these large reptiles are now common in freshwater marshlands (and some brackish areas) of the Coastal Plain; they are especially numerous in Florida and Louisiana. Adults feed on a wide variety of fish, reptiles, birds and mammals and can pose a threat to humans if harassed or startled; they have been known to grab pets or even young children on rare occasions. American gators are also raised in captivity for their meat and leathery hide and, unfortunately, are victims of the tourist carnival industry across the Deep South.
Up to 15 feet long and weighing as much as 800 pounds, adult males bellow in mid spring to attract a mate. Once impregnated, the female builds a nest mound of rotting vegetation and deposits 20-50 eggs before covering them with more vegetation. Staying close by until they hatch (usually in August), the mother protects her young, digging them out and carrying them to open water in her mouth; she will continue to watch over her offspring for their first year of life. Those eggs that incubate at temperatures above 90 degrees F produce males while those below 86 degrees produce females; nest temperatures in between these parameters yield a mix of genders.
Young alligators may fall victim to a variety of predators, including snakes, large fish, snapping turtles, raccoons, bobcats, bald eagles and other alligators; once fully grown, however, American gators are threatened only by human hunters and habitat loss and may live 50 years or more in the wild. Nearly driven to extinction by overhunting and swamp drainage during the first half of the 20th Century, these large reptiles are now common in freshwater marshlands (and some brackish areas) of the Coastal Plain; they are especially numerous in Florida and Louisiana. Adults feed on a wide variety of fish, reptiles, birds and mammals and can pose a threat to humans if harassed or startled; they have been known to grab pets or even young children on rare occasions. American gators are also raised in captivity for their meat and leathery hide and, unfortunately, are victims of the tourist carnival industry across the Deep South.
Thursday, January 26, 2012
Mixing Oil & Wetlands
Since I drive a car and heat my home, it would be hypocritical of me to renounce oil production in the U.S. or elsewhere across the globe. Nevertheless, the oil industry has a tendency to minimize its potential impact on wetlands, the most productive ecosystems on our planet.
Sabine National Wildlife Refuge, in extreme southwest Louisiana, is the largest wetland preserve along the Gulf Coast, renowned for its large flocks of wintering waterfowl, its wide variety of wading birds and its resident population of American alligators and wetland mammals. Yet, oil production continues on this preserve despite a significant spill during the winter of 2002-2003 and the devastation of Hurricane Rita, in September, 2005, which spread more than 1400 barrels of toxic chemicals across the refuge. More recently, shortcuts in the startup of BP's Deepwater Horizon inundated coastal marshlands with crude oil, the worst man-made disaster in the history of the Gulf of Mexico. Now, despite concerns for potential damage to wetlands and groundwater across the unique sandhills ecosystem of western Nebraska, conservative politicians and their oil company supporters are attempting to push through the Keystone Pipeline Project before appropriate environmental studies are complete. And, of course, conservationists have been battling proposals to drill in the Arctic National Wildlife Refuge for decades.
While we cannot replace fossil fuels with "green" sources of energy overnight, it is equally short-sighted for the oil industry to minimize its impact on fragile and vital ecosystems across our planet. Oil and wetlands will not mix and we destroy those crucibles of life at our own peril.
Sabine National Wildlife Refuge, in extreme southwest Louisiana, is the largest wetland preserve along the Gulf Coast, renowned for its large flocks of wintering waterfowl, its wide variety of wading birds and its resident population of American alligators and wetland mammals. Yet, oil production continues on this preserve despite a significant spill during the winter of 2002-2003 and the devastation of Hurricane Rita, in September, 2005, which spread more than 1400 barrels of toxic chemicals across the refuge. More recently, shortcuts in the startup of BP's Deepwater Horizon inundated coastal marshlands with crude oil, the worst man-made disaster in the history of the Gulf of Mexico. Now, despite concerns for potential damage to wetlands and groundwater across the unique sandhills ecosystem of western Nebraska, conservative politicians and their oil company supporters are attempting to push through the Keystone Pipeline Project before appropriate environmental studies are complete. And, of course, conservationists have been battling proposals to drill in the Arctic National Wildlife Refuge for decades.
While we cannot replace fossil fuels with "green" sources of energy overnight, it is equally short-sighted for the oil industry to minimize its impact on fragile and vital ecosystems across our planet. Oil and wetlands will not mix and we destroy those crucibles of life at our own peril.
Wednesday, January 25, 2012
Harney Basin
Harney Basin is a geologic and topographic basin in southeast Oregon; while it sits adjacent to the northwest corner of the Great Basin, it is separated from that province by the massive fault-block of the Steens Mountain ridge. On its north side, the Harney Basin is bordered by the southern edge of the Blue Mountains while a high lava plain separates the basin from the watersheds of the John Day and Klamath Rivers to the northwest and southwest, respectively.
During warm interglacial periods of the Pleistocene, glacial meltwater from the adjacent highlands filled the Harney Basin, spilling northeastward into the Malheur River, a tributary of the Snake River. Today, as the climate has warmed through the Holocene, the floor of Harney Basin has become a high desert, receiving only 6 inches of precipitation each year; a low divide along the basin's northeast edge, formerly a spillway, now completes the basin topography and all streams flow inward toward Harney and Malheur Lakes, on the basin's floor. Burns, Oregon, is the only sizable town in this remote, high desert basin.
While most of the basin floor is high and dry, with elevations between 4000 and 5200 feet, Malheur Lake, fed by the Silvies River from the Blue Mountains and the Blitzen River from Steens Mountain, provides a rich and welcome oasis for migrant waterfowl, shorebirds, white pelicans and sandhill cranes. Home to many other species as well, the lake and its wetlands are protected as the Malheur National Wildlife Refuge; during seasons with heavy precipitation or snowmelt, Malheur Lake spills west toward Harney Lake, an ephemeral, salt pan lake that is the topographic sink of Harney Basin.
During warm interglacial periods of the Pleistocene, glacial meltwater from the adjacent highlands filled the Harney Basin, spilling northeastward into the Malheur River, a tributary of the Snake River. Today, as the climate has warmed through the Holocene, the floor of Harney Basin has become a high desert, receiving only 6 inches of precipitation each year; a low divide along the basin's northeast edge, formerly a spillway, now completes the basin topography and all streams flow inward toward Harney and Malheur Lakes, on the basin's floor. Burns, Oregon, is the only sizable town in this remote, high desert basin.
While most of the basin floor is high and dry, with elevations between 4000 and 5200 feet, Malheur Lake, fed by the Silvies River from the Blue Mountains and the Blitzen River from Steens Mountain, provides a rich and welcome oasis for migrant waterfowl, shorebirds, white pelicans and sandhill cranes. Home to many other species as well, the lake and its wetlands are protected as the Malheur National Wildlife Refuge; during seasons with heavy precipitation or snowmelt, Malheur Lake spills west toward Harney Lake, an ephemeral, salt pan lake that is the topographic sink of Harney Basin.
Tuesday, January 24, 2012
Mt. Shasta
Towering above the landscape of Northern California, at the southern end of the Cascade Range, Mt. Shasta is a composite of four volcanic cones, the first of which began to form just 600,000 years ago; with a summit elevation of 14,179 feet, it is second only to Mt. Ranier among the Cascade volcanoes.
The current summit crater of Mt. Shasta, 600 feet across, tops the Hotlum Cone, which formed about 8000 years ago and has been erupting every 600-800 years; the last significant eruption was 200 years ago. Mt. Shastina, topping out at 12,330 feet, is an older cone that now appears as a prominant satellite peak to the west of Shasta's primary summit; the Whitney Glacier, one of five glaciers that grace Mt. Shasta, lies between the two peaks. Tributaries arising from Shasta's ice sheets feed the Klamath River to the north (primarily via the Shasta River) and the Sacramento River, to the south.
Since Mt. Shasta rises almost 10,000 feet above its immediate surroundings, this magnificent massif can be seen from up to 150 miles away. Though classified as a dormant volcano, Shasta is not extinct, as indicated by active fumeroles along its flanks. Another explosive eruption is expected within a few hundred years....if not next month!
The current summit crater of Mt. Shasta, 600 feet across, tops the Hotlum Cone, which formed about 8000 years ago and has been erupting every 600-800 years; the last significant eruption was 200 years ago. Mt. Shastina, topping out at 12,330 feet, is an older cone that now appears as a prominant satellite peak to the west of Shasta's primary summit; the Whitney Glacier, one of five glaciers that grace Mt. Shasta, lies between the two peaks. Tributaries arising from Shasta's ice sheets feed the Klamath River to the north (primarily via the Shasta River) and the Sacramento River, to the south.
Since Mt. Shasta rises almost 10,000 feet above its immediate surroundings, this magnificent massif can be seen from up to 150 miles away. Though classified as a dormant volcano, Shasta is not extinct, as indicated by active fumeroles along its flanks. Another explosive eruption is expected within a few hundred years....if not next month!
Sunday, January 22, 2012
Return to Winter
Ah, the wonders of modern travel. Strolling on a sun-drenched beach one day and trudging through an icy fog the next. No roseate spoonbills to brighten our morning, just the bulky form of a red-tailed hawk, hunched on a roadside limb. No noisy chatter from those carefree gulls and terns, just the raucous, indignant calls of our jays and crows.
Many humans, true to our tropical heritage, would love to spend their lives in the balmy climate of South Florida. But some of us, including most naturalists, I suspect, favor life in the Temperate Zone, with its broad seasonal fluctuation; variety, as they say, is the spice of life and those of us at middle latitudes surely experience a great deal of variety (annual if not weekly). While nature has her cycle in the Subtropics as well, her patterns are more dramatic in northern climes; besides, those of us who endure the hardships of winter are more likely to appreciate the steady, if not even, advance of spring.
So, while our splendid respite was all too short, I welcome our return to winter, with its raw, somber days and clear, frigid nights. What we really need is a good snowstorm, an event often envied by those from the land of perpetual summer.
Many humans, true to our tropical heritage, would love to spend their lives in the balmy climate of South Florida. But some of us, including most naturalists, I suspect, favor life in the Temperate Zone, with its broad seasonal fluctuation; variety, as they say, is the spice of life and those of us at middle latitudes surely experience a great deal of variety (annual if not weekly). While nature has her cycle in the Subtropics as well, her patterns are more dramatic in northern climes; besides, those of us who endure the hardships of winter are more likely to appreciate the steady, if not even, advance of spring.
So, while our splendid respite was all too short, I welcome our return to winter, with its raw, somber days and clear, frigid nights. What we really need is a good snowstorm, an event often envied by those from the land of perpetual summer.
Saturday, January 21, 2012
Along the Myakka
The Myakka River, in southwest Florida, one of only two rivers designated "Wild & Scenic" by the Sunshine State, rises in northern Manatee County and flows southward for 60 miles to Charlotte Harbor. Along the way, it passes through the lakes and marshlands of Myakka River State Park, east of Sarasota, and encounters little human development for much of its course; indeed, Sarasota County has been especially committed to protecting its natural channel and three preserves offer access to southern portions of this ecosystem.
Having enjoyed a week along the Gulf Coast, we decided to head inland and explore the lower Myakka corridor. Jelks Preserve, about two miles south of I-75 on North River Road (via the North Port/Englewood Exit), provides an excellent overview of natural habitats along the river as well as scenic views of the Myakka itself; oak hammocks, festooned with Spanish moss, border slash pine flatwoods, marsh-lined ponds and scrub meadows. Armadillos were abundant along the sandy trails, black vultures and bald eagles soared overhead and American alligators, though unseen on our visit, haunt the shallow pools and wetlands. Myakka River State Forest, about 5 miles south of U.S. 41 via River Road, offers an extensive network of trail loops through these same habitats; it was there that we encountered a massive flock of wintering tree swallows, surely numbering in the thousands, and watched a trio of Florida sandhill cranes drift across the bright blue sky. Finally, Myakka Islands Point, a Sarasota County preserve west of North Port, provides access to pine flatwoods (dominated by slash pine, cabbage palm and saw palmetto) which overlook broad swaths of riverside marsh.
South of these preserves the Myakka becomes increasing brackish as it receives tidal inflow; in concert, the river leaves its meandering, tree-lined corridor and open marshlands stretch across its broad floodplain. Alligators that bask along the River's more northern shores avoid these salty waters but manatees, moving in from the bay, now inhabit the Myakka. As expected, wading birds are abundant across this vibrant tidal zone, roosting in tree islands that rise above the marsh.
Having enjoyed a week along the Gulf Coast, we decided to head inland and explore the lower Myakka corridor. Jelks Preserve, about two miles south of I-75 on North River Road (via the North Port/Englewood Exit), provides an excellent overview of natural habitats along the river as well as scenic views of the Myakka itself; oak hammocks, festooned with Spanish moss, border slash pine flatwoods, marsh-lined ponds and scrub meadows. Armadillos were abundant along the sandy trails, black vultures and bald eagles soared overhead and American alligators, though unseen on our visit, haunt the shallow pools and wetlands. Myakka River State Forest, about 5 miles south of U.S. 41 via River Road, offers an extensive network of trail loops through these same habitats; it was there that we encountered a massive flock of wintering tree swallows, surely numbering in the thousands, and watched a trio of Florida sandhill cranes drift across the bright blue sky. Finally, Myakka Islands Point, a Sarasota County preserve west of North Port, provides access to pine flatwoods (dominated by slash pine, cabbage palm and saw palmetto) which overlook broad swaths of riverside marsh.
South of these preserves the Myakka becomes increasing brackish as it receives tidal inflow; in concert, the river leaves its meandering, tree-lined corridor and open marshlands stretch across its broad floodplain. Alligators that bask along the River's more northern shores avoid these salty waters but manatees, moving in from the bay, now inhabit the Myakka. As expected, wading birds are abundant across this vibrant tidal zone, roosting in tree islands that rise above the marsh.
Friday, January 20, 2012
A Free Dolphin Show
Never a fan of Disney-esque human-wildlife bonding films and personally concerned about the new wave of ecotourism that baits wild creatures for close human encounters, I favor granting our wild neighbors their space, satisfied to observe them at a safe and non-threatening distance. But yesterday afternoon, as I sat on our seawall along Sarasota Bay, a dolphin chose to pay a visit.
Racing along the wall, he repeatedly turned his head to glance at me as he chased a school of fish. Catching one in his mouth, he tossed it into the air several times before ingesting the meal. At one point, he stretched out on the surface, looked in my direction and then sped toward the wall, performing a flip turn just before impact. The show continued for about ten minutes before he tired of the performance and swam off to the south. I have no doubt that his antics were a means of communication, perhaps an attempt to encourage my participation.
Most of all, this delightful experience reinforced my conviction that whales and dolphins are too intelligent to be held in captivity. No amount of tasty fish or audience appreciation can justify their loss of freedom.
Racing along the wall, he repeatedly turned his head to glance at me as he chased a school of fish. Catching one in his mouth, he tossed it into the air several times before ingesting the meal. At one point, he stretched out on the surface, looked in my direction and then sped toward the wall, performing a flip turn just before impact. The show continued for about ten minutes before he tired of the performance and swam off to the south. I have no doubt that his antics were a means of communication, perhaps an attempt to encourage my participation.
Most of all, this delightful experience reinforced my conviction that whales and dolphins are too intelligent to be held in captivity. No amount of tasty fish or audience appreciation can justify their loss of freedom.
Thursday, January 19, 2012
Smart Phone Stress
Always behind the curve when it comes to technology, I use a flip-top cell phone that I bought in 2004. It still provides clear voice communication and texting (which I rarely use) but, of course, does not have GPS, internet service or the numerous applications available on the modern smart phones.
Then again, I check my email twice a day (on my laptop) and can speak with friends, family or emergency services whenever necessary. I don't need GPS to explore the countryside and can't imagine watching movies, sporting events or other programming on the tiny screen of a cell phone. Of course, I'm not on Facebook, have never tweeted, despise computer games and prefer old fashion paperback books.
Most importantly, though, I enjoy a reasonable degree of solitude and am not tempted to instantly review every email that comes my way. While others may scoff at my antiquated concept of modern communication, I suggest that they are being unnecessarily stressed by a bombardment of messages from friends, business associates and spam producers. For the younger generation, who have grown up staring at various forms of computer screens, this lifestyle may be perfectly comfortable but the use of smart phones by older adults likely comes with a price that they do not recognize.
Then again, I check my email twice a day (on my laptop) and can speak with friends, family or emergency services whenever necessary. I don't need GPS to explore the countryside and can't imagine watching movies, sporting events or other programming on the tiny screen of a cell phone. Of course, I'm not on Facebook, have never tweeted, despise computer games and prefer old fashion paperback books.
Most importantly, though, I enjoy a reasonable degree of solitude and am not tempted to instantly review every email that comes my way. While others may scoff at my antiquated concept of modern communication, I suggest that they are being unnecessarily stressed by a bombardment of messages from friends, business associates and spam producers. For the younger generation, who have grown up staring at various forms of computer screens, this lifestyle may be perfectly comfortable but the use of smart phones by older adults likely comes with a price that they do not recognize.
Wednesday, January 18, 2012
Comb Jellies
On our regular trips to Longboat Key, Florida, we encounter a spectacular diversity of wildlife, including dolphins, manatees, stingrays, ghost crabs and a wide variety of coastal birds. But yesterday afternoon, while sitting on a seawall along Sarasota Bay, I observed a flotilla of comb jellies for the first time. Drifting in the calm bay waters, they looked like miniature Goodyear Blimps, complete with neon messages, flashing along their transparent hides.
Members of the phyllum Ctenophora, these marine invertebrates consist of an ovoid mass of gelatinous tissue, enveloped in a thin ectoderm and pierced from front to back by a primitive gastrointestinal tract. On its outer surface are eight lines of cilia, which beat in a coordinated fashion to propel the jelly through the seawater; nevertheless, most of their movement is subject to currents and tides. Carnivores, comb jellies are devoid of stinging tentacles but are ravenous in their consumption of microscopic plankton. Like many other marine invertebrates, these jellyfish are hermaphrodites, producing both eggs and sperm; fertilization usually occurs in the open water but, in some species, takes place within the gut and the offspring are not released until their early development has begun.
My research turned up some disagreement on the source of the iridescent green and orange that flashed along their otherwise transparent bodies. Some attribute these bright colors to sunlight refraction by the beating cilia while others mention the presence of bioluminescence, originating in gastrovascular tubes beneath the lines of cilia. Based on my personal observations, I would favor the latter since the linear displays occurred in shaded waters, adjacent to the seawall. Whatever the source of their colorful light shows, the chance observation of these fascinating creatures was a unique and rewarding experience.
Members of the phyllum Ctenophora, these marine invertebrates consist of an ovoid mass of gelatinous tissue, enveloped in a thin ectoderm and pierced from front to back by a primitive gastrointestinal tract. On its outer surface are eight lines of cilia, which beat in a coordinated fashion to propel the jelly through the seawater; nevertheless, most of their movement is subject to currents and tides. Carnivores, comb jellies are devoid of stinging tentacles but are ravenous in their consumption of microscopic plankton. Like many other marine invertebrates, these jellyfish are hermaphrodites, producing both eggs and sperm; fertilization usually occurs in the open water but, in some species, takes place within the gut and the offspring are not released until their early development has begun.
My research turned up some disagreement on the source of the iridescent green and orange that flashed along their otherwise transparent bodies. Some attribute these bright colors to sunlight refraction by the beating cilia while others mention the presence of bioluminescence, originating in gastrovascular tubes beneath the lines of cilia. Based on my personal observations, I would favor the latter since the linear displays occurred in shaded waters, adjacent to the seawall. Whatever the source of their colorful light shows, the chance observation of these fascinating creatures was a unique and rewarding experience.
Tuesday, January 17, 2012
Lonesome Loon
Among the many seabirds that have graced Sarasota Bay this week has been a solitary common loon. Staying close to the seawall behind our condo, this winter resident has remained in the area for the past several days and does not appear to be joining his fellow loons at night.
Breeding across Alaska, Canada, New England and the Upper Great Lakes region, common loons winter primarily on coastal bays and estuaries of North America; some may spend the winter on large inland lakes and reservoirs. While they often gather in loose flocks to roost on the open water, wintering loons usually feed alone and are often solitary when encountered. Diving repeatedly to catch small fish, invertebrates and aquatic larvae, they are rapid and agile swimmers, propelling themselves with their webbed feet; our visitor has often stayed below the surface for a minute or more but common loons are capable of remaining underwater for 5 minutes. As I have noted this week, they seldom return to the surface with prey in their bill, preferring to consume their victims while still underwater.
Built for an aquatic lifestyle, common loons have solid bones to aid diving and their feet are placed far back on their streamlined body; indeed, they find it difficult to maneuver on land and come ashore only to nest. Converting from their striking summer plumage to a duller, two-tone outfit in winter, common loons molt their flight feathers in mid winter and are unable to fly for a month or so; this may explain why our lonesome loon has not moved on to join his fellow migrants. For now, we'll enjoy watching his aquatic skills but, unfortunately, will not be treated to his yodeling or eerie wail; those calls, reminiscent of northern lake country, are rarely delivered on the loon's wintering grounds.
Breeding across Alaska, Canada, New England and the Upper Great Lakes region, common loons winter primarily on coastal bays and estuaries of North America; some may spend the winter on large inland lakes and reservoirs. While they often gather in loose flocks to roost on the open water, wintering loons usually feed alone and are often solitary when encountered. Diving repeatedly to catch small fish, invertebrates and aquatic larvae, they are rapid and agile swimmers, propelling themselves with their webbed feet; our visitor has often stayed below the surface for a minute or more but common loons are capable of remaining underwater for 5 minutes. As I have noted this week, they seldom return to the surface with prey in their bill, preferring to consume their victims while still underwater.
Built for an aquatic lifestyle, common loons have solid bones to aid diving and their feet are placed far back on their streamlined body; indeed, they find it difficult to maneuver on land and come ashore only to nest. Converting from their striking summer plumage to a duller, two-tone outfit in winter, common loons molt their flight feathers in mid winter and are unable to fly for a month or so; this may explain why our lonesome loon has not moved on to join his fellow migrants. For now, we'll enjoy watching his aquatic skills but, unfortunately, will not be treated to his yodeling or eerie wail; those calls, reminiscent of northern lake country, are rarely delivered on the loon's wintering grounds.
Monday, January 16, 2012
Subtle Racism
The courageous work of Martin Luther King and his colleagues drew our attention to the overt manifestations of racial discrimination in America and also uncovered the subtle, more insidious forms of racism that pervade our society. Having come of age in the 1960s, the images of vicious attacks on civil rights demonstrators are burned in my memory but so are the tempered reactions of many white adults to the words of Reverend King; in their eyes, he was a troublemaker, unwelcome in our non-racist, Midwestern city.
Today, while most Americans condemn the outward expression of racial discrimination and civil rights legislation has eliminated the more egregious forms of public intolerance, there remains a subtle undercurrent of racism in our country. This toxic attitude, expressed in private and revealed by the spontaneous comments of politicians, businessmen and other community leaders, is reflected by our tendency to define human society by its racial and ethnic groups. In doing so, we make assumptions about individuals based solely on their cultural heritage and convince ourselves that we cannot trust those from other segments of society. Indeed, it is clear to me that President Obama has faced racial headwinds throughout his first term in office and that the current field of Republican opponents are tapping into American racial bias whenever possible.
Present long before the Civil War, racism reflects an ingrained tribalism that has governed human civilization throughout our history. Intolerance of others, whether based on race, religion, ethnic background or socioeconomic status, has always characterized human society. Until we evolve beyond this primitive mindset, the prospects for true equality and justice are faint indeed.
Today, while most Americans condemn the outward expression of racial discrimination and civil rights legislation has eliminated the more egregious forms of public intolerance, there remains a subtle undercurrent of racism in our country. This toxic attitude, expressed in private and revealed by the spontaneous comments of politicians, businessmen and other community leaders, is reflected by our tendency to define human society by its racial and ethnic groups. In doing so, we make assumptions about individuals based solely on their cultural heritage and convince ourselves that we cannot trust those from other segments of society. Indeed, it is clear to me that President Obama has faced racial headwinds throughout his first term in office and that the current field of Republican opponents are tapping into American racial bias whenever possible.
Present long before the Civil War, racism reflects an ingrained tribalism that has governed human civilization throughout our history. Intolerance of others, whether based on race, religion, ethnic background or socioeconomic status, has always characterized human society. Until we evolve beyond this primitive mindset, the prospects for true equality and justice are faint indeed.
Sunday, January 15, 2012
From Snow to Surf
Once again, we have escaped the Midwestern winter for a week in South Florida. Leaving the cold, snowy landscape of Missouri yesterday afternoon, we arrived at our condo on Longboat Key at sunset, under clear but cool skies. This morning, with the temperature in the upper 30s F, we awoke to low tide on Sarasota Bay.
Despite the chilly temperature, a great variety of waterbirds had gathered in the shallows. Great egrets dominated the scene, joined by smaller flocks of white pelicans, double-crested cormorants, snowy egrets, little blue herons, white ibis, pied billed grebes and red-breasted mergansers. A lone wood stork, several great blue herons and a handful of yellow-crowned night herons foraged along the mangrove islands while brown pelicans and royal terns dove for their morning meal.
Once the January sun had tempered the morning chill, we headed to the Gulf side of the Key for a walk along Longboat's uncrowded beach. Due to little wind over the past few days, the Gulf was flat and placid and only a low, gentle surf lapped the shoreline. Laughing gulls, royal terns and sandwich terns basked on the modest dunes while squadrons of brown pelicans undulated across the calm, blue sea. Walking barefoot on the cool sand, our memories of recent frigid nights and windblown snow quickly faded in the warm, morning sun.
Despite the chilly temperature, a great variety of waterbirds had gathered in the shallows. Great egrets dominated the scene, joined by smaller flocks of white pelicans, double-crested cormorants, snowy egrets, little blue herons, white ibis, pied billed grebes and red-breasted mergansers. A lone wood stork, several great blue herons and a handful of yellow-crowned night herons foraged along the mangrove islands while brown pelicans and royal terns dove for their morning meal.
Once the January sun had tempered the morning chill, we headed to the Gulf side of the Key for a walk along Longboat's uncrowded beach. Due to little wind over the past few days, the Gulf was flat and placid and only a low, gentle surf lapped the shoreline. Laughing gulls, royal terns and sandwich terns basked on the modest dunes while squadrons of brown pelicans undulated across the calm, blue sea. Walking barefoot on the cool sand, our memories of recent frigid nights and windblown snow quickly faded in the warm, morning sun.
Friday, January 13, 2012
Raptor Hunt
The farmlands of the American West attract a wide variety of raptors and winter is perhaps the best season to observe them. Buteos and large owls are easier to spot in the barren woodlands and the demands of this harsh season ensure that both prey and hunters are especially active. In addition, the songbird flocks of winter provide tempting targets for accipiters and falcons.
Having convinced myself of these facts, I set out on this bright, frigid day on a circuit through the farmlands that surround Columbia. Red-tailed hawks, as expected, were common and American kestrels were spaced along the rural power lines but other raptors did not cooperate with my well-conceived plan; only a lone red-shouldered hawk, hunched on a creekside limb, made an appearance. Though I scoured the grasslands east of town for a short-eared owl and searched the Missouri River floodplain for a bald eagle, my efforts were in vain. Were it not for the beautiful countryside and a wealth of rural songbirds, I might have been disappointed.
As any experienced birder can attest, when it comes to finding their quarry, the expected does not always occur and the unexpected often ends up providing the highlight of the day. On this trip, neither the expected nor the unexpected materialized. Then again, it's the adventure of the hunt that counts and, as they proclaim on those ads for miraculous potions, results may vary.
Having convinced myself of these facts, I set out on this bright, frigid day on a circuit through the farmlands that surround Columbia. Red-tailed hawks, as expected, were common and American kestrels were spaced along the rural power lines but other raptors did not cooperate with my well-conceived plan; only a lone red-shouldered hawk, hunched on a creekside limb, made an appearance. Though I scoured the grasslands east of town for a short-eared owl and searched the Missouri River floodplain for a bald eagle, my efforts were in vain. Were it not for the beautiful countryside and a wealth of rural songbirds, I might have been disappointed.
As any experienced birder can attest, when it comes to finding their quarry, the expected does not always occur and the unexpected often ends up providing the highlight of the day. On this trip, neither the expected nor the unexpected materialized. Then again, it's the adventure of the hunt that counts and, as they proclaim on those ads for miraculous potions, results may vary.
Thursday, January 12, 2012
Winter Plunges South
After a week of spring-like weather across much of the country, winter has returned with a vengeance, plunging southward along the east slope of the Rockies and across the Great Plains. The leading edge of this Arctic front passed through Columbia late last evening, producing two inches of snow and dropping our temperature by 30 degrees F overnight. This morning, with residual flurries and a gusty northwest wind, it is 17 degrees in central Missouri.
To our northeast, low pressure is strengthening over the Great Lakes and is forecast to bring the first major snowstorm of the season to that region before heading toward New England. In concert, polar air will invade the northern U.S., temporarily erasing any memories of a mild winter season.
Once again, this storm front has dropped from Canada into the Heartland, bypassing areas west of the Continental Divide and providing no relief from the western snow drought. In fact, another atmospheric ridge will develop behind this winter storm, ushering warm, dry air across the Intermountain West and High Plains. Hopefully, the stagnant jet stream pattern will soon shift, directing Pacific moisture toward the Sierra Nevada, Wasatch Front and western slope of the Rockies. If not, the mild, dry winter across the West will come with a very steep price.
To our northeast, low pressure is strengthening over the Great Lakes and is forecast to bring the first major snowstorm of the season to that region before heading toward New England. In concert, polar air will invade the northern U.S., temporarily erasing any memories of a mild winter season.
Once again, this storm front has dropped from Canada into the Heartland, bypassing areas west of the Continental Divide and providing no relief from the western snow drought. In fact, another atmospheric ridge will develop behind this winter storm, ushering warm, dry air across the Intermountain West and High Plains. Hopefully, the stagnant jet stream pattern will soon shift, directing Pacific moisture toward the Sierra Nevada, Wasatch Front and western slope of the Rockies. If not, the mild, dry winter across the West will come with a very steep price.
Wednesday, January 11, 2012
The Winter Forest
The winter forest does not offer the attractive wildflowers of early spring, the fragrant humidity of a summer morning or the brilliant foliage of glorious October. Neither does it promise the explosion of life encountered during the warmer months: those colorful birds, agile lizards, slithering snakes and buzzing insects. But the winter forest harbors its own gifts.
First and foremost is the silence, broken only by the distant call of jays, the drumming of woodpeckers and the twittering of songbird groups as they roam through the woodland. Then there is that fresh, invigorating air, often scented by woodsmoke from a nearby farmhouse; unlike the shaded summer woods, the barren forest welcomes the sun and long shadows stretch across its leaf-covered floor. Hiking along its frozen trails or trudging through its crunchy snow, the naturalist hopes to spot an owl on its daytime roost; perhaps a saw-whet owl in the cedars or a screech owl peering from a tree cavity.
Above all else, the winter forest offers solitude, an escape from the turmoil of human society and a chance to meet nature on her own terms. If prepared with warm, layered clothing and good hiking boots, those who venture into the winter woods soon experience the many benefits to both body and soul.
First and foremost is the silence, broken only by the distant call of jays, the drumming of woodpeckers and the twittering of songbird groups as they roam through the woodland. Then there is that fresh, invigorating air, often scented by woodsmoke from a nearby farmhouse; unlike the shaded summer woods, the barren forest welcomes the sun and long shadows stretch across its leaf-covered floor. Hiking along its frozen trails or trudging through its crunchy snow, the naturalist hopes to spot an owl on its daytime roost; perhaps a saw-whet owl in the cedars or a screech owl peering from a tree cavity.
Above all else, the winter forest offers solitude, an escape from the turmoil of human society and a chance to meet nature on her own terms. If prepared with warm, layered clothing and good hiking boots, those who venture into the winter woods soon experience the many benefits to both body and soul.
Tuesday, January 10, 2012
Trumpeters at Riverlands
The Riverlands Migratory Bird Sanctuary, north of St. Louis, does not occupy pristine natural landscape; transmission lines, with their huge metal towers, stretch along the west boundary of the 1200 acre preserve, homes and buildings of Alton, Illinois, cover the ridge to the east, power plant chimneys rise in various directions and the massive, concrete bulk of the Melvin Price Locks and Dam looms at its southeast corner. Nevertheless, the fields, ponds, lakes and wetlands of this refuge are magnets for migratory waterfowl, shorebirds, waders and songbirds as they travel along the Mississippi River and provide winter habitat for a variety of species.
Over the past decade or so, trumpeter swans have joined those migrants as this species has been re-established across the Upper Midwest. Last winter, 500 trumpeters wintered at Riverlands, the largest seasonal flock to date; according to refuge personnel, approximately 700 of these swans were in the vicinity just before the Holidays but most have dispersed to other areas and some 200 remain on the refuge at present. Indeed, on my visit this morning, they were the most common bird at Riverlands, gathering in loose flocks on the shallow pools west of the roadway; they were joined by a small number of tundra swans, difficult to distinguish at a distance but betrayed by their high-pitched whoops, contrasting with the nasal honks of the trumpeters.
Among the other winter residents and visitors were two flocks of greater white-fronted geese, a dozen or so bald eagles, a large flock of ruddy ducks, numerous common goldeneyes and a fair number of canvasbacks. Northern harriers patrolled the grasslands and small flocks of Canada geese moved among the wetlands. Surprise visitors were three American white pelicans and a handful of double-crested cormorants, still up north due to our mild early winter. But the trumpeters had prompted my visit and I was not disappointed; as usual, their wild chatter and majestic flights were the highlight of my morning.
Over the past decade or so, trumpeter swans have joined those migrants as this species has been re-established across the Upper Midwest. Last winter, 500 trumpeters wintered at Riverlands, the largest seasonal flock to date; according to refuge personnel, approximately 700 of these swans were in the vicinity just before the Holidays but most have dispersed to other areas and some 200 remain on the refuge at present. Indeed, on my visit this morning, they were the most common bird at Riverlands, gathering in loose flocks on the shallow pools west of the roadway; they were joined by a small number of tundra swans, difficult to distinguish at a distance but betrayed by their high-pitched whoops, contrasting with the nasal honks of the trumpeters.
Among the other winter residents and visitors were two flocks of greater white-fronted geese, a dozen or so bald eagles, a large flock of ruddy ducks, numerous common goldeneyes and a fair number of canvasbacks. Northern harriers patrolled the grasslands and small flocks of Canada geese moved among the wetlands. Surprise visitors were three American white pelicans and a handful of double-crested cormorants, still up north due to our mild early winter. But the trumpeters had prompted my visit and I was not disappointed; as usual, their wild chatter and majestic flights were the highlight of my morning.
Monday, January 9, 2012
A Frosty Floodplain
As I entered Eagle Bluffs Conservation Area this morning, the sun was just clearing the wooded ridge along the east edge of the Missouri River floodplain. In concert, it illuminated a heavy frost that coated the fields, marshlands and barren woods of the refuge. Ice-covered shallows had flooded the crop stubble but, thanks to our mild winter, the ponds and lakes remained open.
Heading southward through the preserve, I noticed the bulky silhouettes of red-tailed and red-shouldered hawks, spaced along the wood margins, and saw a pair of bald eagles, perched in a large cottonwood. Northern harriers strafed the fields, squadrons of restless ducks and gulls wheeled overhead and stoic great blue herons waded through the icy pools. A belted kingfisher, noisy as ever, hunted above the primary channel while armadas of American coot docked on the east side of muskrat mounds to catch the morning sun. Winter sparrows and juncos flashed across the roadway, diving into thickets to evade the harriers, and a pair of downies picked their way through a grove of saplings.
Mallards and gadwall dominated the waterfowl population, joined by small flocks of lesser scaup, ring-necked ducks and wood ducks. Canada geese, already dispersed into their monogamous pairs, mingled with the ducks and, as noted above, coot were unusually common for this time of year, another reflection of our mild early winter. Though I hoped to encounter some of the trumpeter swans that are wintering in Missouri, none were evident at Eagle Bluffs this morning; that goal should be reached tomorrow, when I pay a mid winter visit to the Riverlands nature preserve, just north of St. Louis.
Heading southward through the preserve, I noticed the bulky silhouettes of red-tailed and red-shouldered hawks, spaced along the wood margins, and saw a pair of bald eagles, perched in a large cottonwood. Northern harriers strafed the fields, squadrons of restless ducks and gulls wheeled overhead and stoic great blue herons waded through the icy pools. A belted kingfisher, noisy as ever, hunted above the primary channel while armadas of American coot docked on the east side of muskrat mounds to catch the morning sun. Winter sparrows and juncos flashed across the roadway, diving into thickets to evade the harriers, and a pair of downies picked their way through a grove of saplings.
Mallards and gadwall dominated the waterfowl population, joined by small flocks of lesser scaup, ring-necked ducks and wood ducks. Canada geese, already dispersed into their monogamous pairs, mingled with the ducks and, as noted above, coot were unusually common for this time of year, another reflection of our mild early winter. Though I hoped to encounter some of the trumpeter swans that are wintering in Missouri, none were evident at Eagle Bluffs this morning; that goal should be reached tomorrow, when I pay a mid winter visit to the Riverlands nature preserve, just north of St. Louis.
Sunday, January 8, 2012
Trust & Doubt
As children, we humans trust everyone and everything. Of course, this reflects the fact that, at that age, we are entirely dependent on others for our basic needs and our worldly experience is extremely limited; indeed, if not closely supervised by adults, children would not survive their first years of life. Later in childhood, as we learn that certain cultural myths are fabrications, designed to mold our behavior, we begin to lose trust in our parents and other adults. By our teenage years, as the drive for independence intensifies, our tendency to doubt the wisdom of authority figures reaches its zenith.
Once unleashed, doubt will accompany us throughout our lives and trust will become its feeble stepsister. As we endure a variety of life changing events, from failed relationships to career setbacks, our ability to trust others is repeatedly tested. In concert with these personal experiences, we witness a litany of public scandals, reinforcing our distrust of political, religious and corporate leaders. Above all else, we come to appreciate the selfish nature of the human animal and exercise caution in our approach to personal, social and business relationships. Of course, love may trump doubt but then love blinds us in so many ways.
This general suppression of trust, accompanied by a willingness to express doubt, is actually healthy in a number of ways. Rather than going with the flow, we become more innovative and creative, feeding the advance of art, science and technology. The rise of entrepreneurism, vital to any dynamic economy, is, in part, driven by the choice to trust one's own knowledge, skills and business instincts. In a broader sense, our willingness to doubt the wisdom of certain governmental policies or cultural practices is the first step toward their eradication. While a certain degree of trust is essential to foster social, commercial and international cooperation, it is doubt that protects human rights and advances our civilization.
Once unleashed, doubt will accompany us throughout our lives and trust will become its feeble stepsister. As we endure a variety of life changing events, from failed relationships to career setbacks, our ability to trust others is repeatedly tested. In concert with these personal experiences, we witness a litany of public scandals, reinforcing our distrust of political, religious and corporate leaders. Above all else, we come to appreciate the selfish nature of the human animal and exercise caution in our approach to personal, social and business relationships. Of course, love may trump doubt but then love blinds us in so many ways.
This general suppression of trust, accompanied by a willingness to express doubt, is actually healthy in a number of ways. Rather than going with the flow, we become more innovative and creative, feeding the advance of art, science and technology. The rise of entrepreneurism, vital to any dynamic economy, is, in part, driven by the choice to trust one's own knowledge, skills and business instincts. In a broader sense, our willingness to doubt the wisdom of certain governmental policies or cultural practices is the first step toward their eradication. While a certain degree of trust is essential to foster social, commercial and international cooperation, it is doubt that protects human rights and advances our civilization.
Saturday, January 7, 2012
Snow Drought
So far, it's been a mild, snowless winter for much of the U.S. and many ski resorts, from California to Maine are desperate for a return to more typical conditions. But while the economic hardship imposed on these communities is of concern, a lack of sufficient snowpack to feed metropolitan reservoirs poses a more significant threat. This is especially true across the American West, where mountain snowfall is the primary source of water for public consumption, industry and agriculture; the dearth of snow in the Sierra Nevada is of particular concern in light of the massive population that resides across the semiarid landscape of Southern California.
The primary culprit for this snow drought appears to be the La Nina weather pattern, characterized by high pressure over the eastern Pacific. In such years, Pacific storms are shunted to the north and onshore moisture flow is shut off along the California coast; some of these storms end up dropping southward through the Rockies (as is occurring today) providing some relief to that region. Indeed, so far this winter, the few significant cold fronts that have invaded the U.S. have plunged from Canada into the Heartland, unaccompanied by Pacific moisture. Some of these atmospheric troughs have ignited snowstorms across the Southwest and Southern Plains as moisture streamed in from the Baja and Gulf of Mexico but the Northern Plains have remained high and dry.
Some climatologists also point to lower atmospheric pressures over the North Atlantic, favoring a mild, southwesterly flow across the Lower 48. Whatever the cause for our warm and snowless winter, it is not likely related to global climate change; one need only recall the severe cold and heavy snows of last winter to realize that our current dilemma does not necessarily represent a developing trend. In fact, current seasonal forecasts, to the extent that they are accurate, predict a return to more typical winter conditions for the remainder of the season. As always, time will tell.
The primary culprit for this snow drought appears to be the La Nina weather pattern, characterized by high pressure over the eastern Pacific. In such years, Pacific storms are shunted to the north and onshore moisture flow is shut off along the California coast; some of these storms end up dropping southward through the Rockies (as is occurring today) providing some relief to that region. Indeed, so far this winter, the few significant cold fronts that have invaded the U.S. have plunged from Canada into the Heartland, unaccompanied by Pacific moisture. Some of these atmospheric troughs have ignited snowstorms across the Southwest and Southern Plains as moisture streamed in from the Baja and Gulf of Mexico but the Northern Plains have remained high and dry.
Some climatologists also point to lower atmospheric pressures over the North Atlantic, favoring a mild, southwesterly flow across the Lower 48. Whatever the cause for our warm and snowless winter, it is not likely related to global climate change; one need only recall the severe cold and heavy snows of last winter to realize that our current dilemma does not necessarily represent a developing trend. In fact, current seasonal forecasts, to the extent that they are accurate, predict a return to more typical winter conditions for the remainder of the season. As always, time will tell.
Friday, January 6, 2012
The Raton Basin
Driving along I-25 between Walsenburg, Colorado, and Raton, New Mexico, one enjoys spectacular scenery, including lofty peaks, high mesas and rugged canyons. One would certainly not imagine that this area was once a basin!
Yet, back in the Cretaceous, some 100 million years ago, when Tyrannosaurus rex and his cohorts roamed the planet and a broad seaway stretched from Texas to western Canada, a geologic basin extended across this region, tilted upward to the west; marine shale, known as Pierre Shale, covered the floor of the basin, deposited by the Cretaceous Sea. As the Rockies began to rise and the sea retreated to the south and east, coastal sands settled on the shale and have since hardened into the sandstone of the Trinidad Formation. Then, toward the end of the Cretaceous, a delta ecosystem spread across the region, destined to yield the shales, siltstones, sandstones and coal seams of the Vermejo Formation; coal has been mined from this formation since the 1800s and methane has been retrieved since the 1980s. As the Cretaceous gave way to the Tertiary Period, alluvial debris from the rising mountains covered the area, the source of conglomerates that now comprise the Raton Formation; harboring pockets of coal, this Formation is famous for its exposure of the K-T boundary, within which a high level of iridium supports the theory that a catastrophic meteor impact ended the Cretaceous and wiped out the dinosaurs. Finally, during the Paleocene, alluvial sands and muds of what is now the Poison Canyon Formation covered any remaining evidence of the underlying geologic basin.
Since then, in concert with continued uplift along the Rocky Mountain corridor, granite intrusions pushed up into the sediments, later to be uncovered by erosion to reveal the spectacular Spanish Peaks of southern Colorado, complete with Eocene-Oligocene lava dikes that formed as these massive plutons rose. In the late Miocene, about 9 million years ago, the Raton-Clayton Volcanic Field developed across northeast New Mexico, spreading thick pools of basalt across what is now the Colorado-New Mexico line. This hard cap of basalt protected the underlying Tertiary and Cretaceous sediments, yielding a chain of high mesas that stretch from the base of the Rockies to the Oklahoma Panhandle, separating the watersheds of the Arkansas and Cimarron Rivers.
Yet, back in the Cretaceous, some 100 million years ago, when Tyrannosaurus rex and his cohorts roamed the planet and a broad seaway stretched from Texas to western Canada, a geologic basin extended across this region, tilted upward to the west; marine shale, known as Pierre Shale, covered the floor of the basin, deposited by the Cretaceous Sea. As the Rockies began to rise and the sea retreated to the south and east, coastal sands settled on the shale and have since hardened into the sandstone of the Trinidad Formation. Then, toward the end of the Cretaceous, a delta ecosystem spread across the region, destined to yield the shales, siltstones, sandstones and coal seams of the Vermejo Formation; coal has been mined from this formation since the 1800s and methane has been retrieved since the 1980s. As the Cretaceous gave way to the Tertiary Period, alluvial debris from the rising mountains covered the area, the source of conglomerates that now comprise the Raton Formation; harboring pockets of coal, this Formation is famous for its exposure of the K-T boundary, within which a high level of iridium supports the theory that a catastrophic meteor impact ended the Cretaceous and wiped out the dinosaurs. Finally, during the Paleocene, alluvial sands and muds of what is now the Poison Canyon Formation covered any remaining evidence of the underlying geologic basin.
Since then, in concert with continued uplift along the Rocky Mountain corridor, granite intrusions pushed up into the sediments, later to be uncovered by erosion to reveal the spectacular Spanish Peaks of southern Colorado, complete with Eocene-Oligocene lava dikes that formed as these massive plutons rose. In the late Miocene, about 9 million years ago, the Raton-Clayton Volcanic Field developed across northeast New Mexico, spreading thick pools of basalt across what is now the Colorado-New Mexico line. This hard cap of basalt protected the underlying Tertiary and Cretaceous sediments, yielding a chain of high mesas that stretch from the base of the Rockies to the Oklahoma Panhandle, separating the watersheds of the Arkansas and Cimarron Rivers.
Thursday, January 5, 2012
The Arctic Falcon
Gyrfalcons are the largest and most powerful falcons on our planet, inhabiting Arctic and Subarctic regions of the globe. Those that live near or above the Arctic Circle are white or pale gray in color while more southern subspecies have various degrees of gray or brown in their plumage.
Solitary for much of the year, adult males and females pair up in March and a clutch of eggs is laid by late April, usually on a bare rock ledge or perhaps in an abandoned raven nest. Both parents incubate the eggs and, within two weeks of hatching, the downy young are left to endure the harsh northern climate while the parents hunt for food; it is then that gyrfalcons are most vulnerable to predation, usually by ravens, skuas or Arctic fox. Those that survive to adulthood have little to fear from natural predators; swift, powerful and agile, they are imposing rivals and may live for 20 years or more.
Gyrfalcons feed primarily on ptarmigan but also attack geese, ducks, gulls and a variety of Arctic songbirds; tundra residents such as Arctic hares, ground squirrels and lemmings are also potential victims. These magnificent raptors, in the style of great white sharks, initially stun their prey with a traumatic collision or chase them to ground before making the kill. During the colder months, gyrfalcons are known to hunt along the pack ice, oblivious to the frigid conditions; though nonmigratory, a few may turn up across the northernmost U.S. in mid to late winter.
Solitary for much of the year, adult males and females pair up in March and a clutch of eggs is laid by late April, usually on a bare rock ledge or perhaps in an abandoned raven nest. Both parents incubate the eggs and, within two weeks of hatching, the downy young are left to endure the harsh northern climate while the parents hunt for food; it is then that gyrfalcons are most vulnerable to predation, usually by ravens, skuas or Arctic fox. Those that survive to adulthood have little to fear from natural predators; swift, powerful and agile, they are imposing rivals and may live for 20 years or more.
Gyrfalcons feed primarily on ptarmigan but also attack geese, ducks, gulls and a variety of Arctic songbirds; tundra residents such as Arctic hares, ground squirrels and lemmings are also potential victims. These magnificent raptors, in the style of great white sharks, initially stun their prey with a traumatic collision or chase them to ground before making the kill. During the colder months, gyrfalcons are known to hunt along the pack ice, oblivious to the frigid conditions; though nonmigratory, a few may turn up across the northernmost U.S. in mid to late winter.
Wednesday, January 4, 2012
Musk Hogs
Collared peccaries, otherwise known as javelinas or by their more colorful title of musk hogs, are native pig-like residents of the Sonoran and Chihuahuan Deserts of the Southwest U.S., from southern Arizona to southwest Texas. They and other peccary species are also found southward through Mexico, Central American and most of South America. All are descendents of a Eurasian ancestor that split from the common pig lineage back in the Eocene, some 50 million years ago.
Living in herds of up to 50 individuals (10-20 is typical), collared peccaries roam the canyons and arroyos of the Desert Southwest, under the control of a dominant male. He breeds with females in the group throughout the year and pregnant females temporarily leave the herd to deliver their young (usually 2) in a den or hollow log. Older sisters help to raise their new siblings and newborn females are sexually mature within a year.
Thinner and longer-legged than common pigs, collared peccaries have a coarse coat of gray-brown hair with a darker mane down their back and a lighter ring around their neck; while their eyesight is rather poor, these desert residents have a keen sense of smell. Short, sharp tusks offer some protection from predators (mountain lions, coyotes, bobcats) but their aggressive nature and group mentality provide their best defence. Omnivorous, peccaries feed on a variety of plant materials (prickly pear cactus and agaves are favored) but also consume eggs, reptiles and carrion; avoiding the heat of mid-day, they usually forage in the early morning and evening hours. The name "musk hog" is derived from the potent musk gland on their upper rump which they use to mark their territory and one another.
Living in herds of up to 50 individuals (10-20 is typical), collared peccaries roam the canyons and arroyos of the Desert Southwest, under the control of a dominant male. He breeds with females in the group throughout the year and pregnant females temporarily leave the herd to deliver their young (usually 2) in a den or hollow log. Older sisters help to raise their new siblings and newborn females are sexually mature within a year.
Thinner and longer-legged than common pigs, collared peccaries have a coarse coat of gray-brown hair with a darker mane down their back and a lighter ring around their neck; while their eyesight is rather poor, these desert residents have a keen sense of smell. Short, sharp tusks offer some protection from predators (mountain lions, coyotes, bobcats) but their aggressive nature and group mentality provide their best defence. Omnivorous, peccaries feed on a variety of plant materials (prickly pear cactus and agaves are favored) but also consume eggs, reptiles and carrion; avoiding the heat of mid-day, they usually forage in the early morning and evening hours. The name "musk hog" is derived from the potent musk gland on their upper rump which they use to mark their territory and one another.
Tuesday, January 3, 2012
Dam Birding
The contruction of dams across this country (and around the globe) has produced a variety of positive and negative effects. On the positive side, dams have been used to prevent flooding, provide a steady supply of water, produce electricity and create lakes for recreational activities such as fishing and boating. Negative effects have included the destruction of natural wetlands and swamp forests, the flooding of canyons and, though often unrecognized, the false security of placing residential and commercial developments on floodplains.
Here in the American Heartland, dams offer another advantage, especially during the winter months. By creating adjacent pools of deep and turbulent water, they yield open feeding areas for a wide variety of birds amidst a cold, frozen landscape. Large flocks of waterfowl often gather behind the dam, including divers such as mergansers, scoters and loons. Below the dam, where fish are stunned by the turbulence, bald eagles, great blue herons and a variety of gulls gather to glean prey from the surface; the common ring-billed and herring gulls are often joined by rare northern species that funnel southward as more northern waterways freeze over.
Of course, these dams also attract a variety of migrants during the spring and fall migrations, when flocks of black and least terns, Franklin's and Bonaparte's gulls, red-breasted mergansers, common loons, Mississippi kites, herons, egrets, white-faced ibis, cormorants and a host of swallows take advantage of fish and insects that congregate near and along these concrete barriers. Despite their negative impact on river ecosystems, dams can offer some damn good birding!
Here in the American Heartland, dams offer another advantage, especially during the winter months. By creating adjacent pools of deep and turbulent water, they yield open feeding areas for a wide variety of birds amidst a cold, frozen landscape. Large flocks of waterfowl often gather behind the dam, including divers such as mergansers, scoters and loons. Below the dam, where fish are stunned by the turbulence, bald eagles, great blue herons and a variety of gulls gather to glean prey from the surface; the common ring-billed and herring gulls are often joined by rare northern species that funnel southward as more northern waterways freeze over.
Of course, these dams also attract a variety of migrants during the spring and fall migrations, when flocks of black and least terns, Franklin's and Bonaparte's gulls, red-breasted mergansers, common loons, Mississippi kites, herons, egrets, white-faced ibis, cormorants and a host of swallows take advantage of fish and insects that congregate near and along these concrete barriers. Despite their negative impact on river ecosystems, dams can offer some damn good birding!
Monday, January 2, 2012
The Arrogance of Certainty
As intelligent creatures, we humans are prone to the arrogance of certainty. We convince ourselves that we completely understand other individuals, other cultures or the field of study in which we have personal experience. Of course, this is rarely, if ever, the case and our assumption leads to personal, domestic, societal or even international conflict.
The long and ongoing battle between science and religion highlights this human trait. Religious zealots often point to the wealth of scientific theories which, in later times, proved to be inaccurate. Yet, this is the nature of science, defined by its sequence from theory to experimentation to conclusion. Furthermore, science has advanced, and will continue to advance, by remaining open to new theories that challenge established doctrine; new data is welcome, whether it supports traditional concepts or redirects our point of view. Religion, on the other hand, based on a belief system that discourages investigation and condemns doubt, is protected by rigid dogma; in the world of the true believer, proof is neither necessary nor desired.
While religion highlights our tendency to be self-righteous, it has plenty of company in the political arena, as the current Republican primary candidates so clearly demonstrate; the invasion of Iraq was, after all, based on the false conviction that Sadam had nuclear weapons. Human society would do well to trade in our arrogance of certainty for a more open-minded and cooperative approach to our many problems.
The long and ongoing battle between science and religion highlights this human trait. Religious zealots often point to the wealth of scientific theories which, in later times, proved to be inaccurate. Yet, this is the nature of science, defined by its sequence from theory to experimentation to conclusion. Furthermore, science has advanced, and will continue to advance, by remaining open to new theories that challenge established doctrine; new data is welcome, whether it supports traditional concepts or redirects our point of view. Religion, on the other hand, based on a belief system that discourages investigation and condemns doubt, is protected by rigid dogma; in the world of the true believer, proof is neither necessary nor desired.
While religion highlights our tendency to be self-righteous, it has plenty of company in the political arena, as the current Republican primary candidates so clearly demonstrate; the invasion of Iraq was, after all, based on the false conviction that Sadam had nuclear weapons. Human society would do well to trade in our arrogance of certainty for a more open-minded and cooperative approach to our many problems.
Sunday, January 1, 2012
The New Year Roars In
No longer keen on late night parties, my wife and I have not witnessed the arrival of a New Year for quite some time. Last evening, however, at the stroke of midnight, I was awakened from sleep, not by the sound of firecrackers but by the rattling of windows and the roar of wind through the barren trees.
After a few days of spring-like weather, a cold front pushed through central Missouri as 2011 gave way to 2012. The balmy conditions of last evening, including the day's high of 61 degrees F, were suddenly retreating to the south as strong, northwest winds dove in behind the front. Not yet subsiding, they have dropped our temperature by 20 degrees and are producing both a wind chill in the teens and a reality check for those of us in the Midwest.
No doubt, some saw a message in that midnight front, an omen of danger for the coming year. But, while the winds arrived in concert with the calendar shift, the calendar itself is an arbitrary creation of human culture, not directly associated with natural events and requiring adjustment every four years. From a naturalist's point of view, the front arrived about nine and a half days after the winter solstice, the true start of nature's year.
After a few days of spring-like weather, a cold front pushed through central Missouri as 2011 gave way to 2012. The balmy conditions of last evening, including the day's high of 61 degrees F, were suddenly retreating to the south as strong, northwest winds dove in behind the front. Not yet subsiding, they have dropped our temperature by 20 degrees and are producing both a wind chill in the teens and a reality check for those of us in the Midwest.
No doubt, some saw a message in that midnight front, an omen of danger for the coming year. But, while the winds arrived in concert with the calendar shift, the calendar itself is an arbitrary creation of human culture, not directly associated with natural events and requiring adjustment every four years. From a naturalist's point of view, the front arrived about nine and a half days after the winter solstice, the true start of nature's year.
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