Monday, May 30, 2016

Tragedy at the Zoo

Throughout my formative years, I was enamored with animals of every kind and visited zoos on a regular basis; in my mind, despite their use of restrictive cages, zoos played an important role in public education and wildlife conservation.  The increasing use of "naturalized enclosures" allayed some of my concerns and I planned to pursue veterinary medicine long before I opted for medical school.

The zoo of my youth was the Cincinnati Zoo, where yesterday's tragedy unfolded; a four-year old boy somehow gained access to the gorilla exhibit and fell into the moat.  This caught the attention of a 17 year-old male gorilla who grabbed the child (perhaps with protective rather than hostile intent), forcing staff members to kill him.  While the cause of this tragedy is under investigation, inadequate fencing and inattentive parenting both surely played a role.

In a larger sense, this tragic event highlights both the potential risks and ethical dilemmas of caging intelligent creatures (primates, elephants, cetaceans, etc.) for our own entertainment, even if a certain degree of education and research is achieved.  The concept of rescuing endangered species for captive breeding and reintroduction to the wild has been unsuccessful in most cases (California condors and black-footed ferrets are two exceptions) and "naturalized exhibits" can never match the freedom and benefits of native habitat.  Though tragedies such as occurred yesterday are rare, the greater tragedy of human-imposed captivity has long been a cherished practice in our culture.  Perhaps, as human enlightenment progresses, we will come to reject the imprisonment of intelligent animals.

Sunday, May 29, 2016

Dickcissel Days at Eagle Bluffs

Driving through Eagle Bluffs Conservation Area this morning, it was clear that the transition from spring migrants to summer residents is well advanced.  Waterfowl were limited to Canada geese, wood ducks, a small flock of blue-winged teal and a few mallards; shorebirds, recently represented by large, mixed flocks are now limited to killdeer and spotted sandpipers.

With the exception of great blue herons, indigo buntings and the ubiquitous red-winged blackbirds, dickcissels were the most conspicuous birds this morning, delivering their distinctive song from the tops of reeds or shrubs; favoring open grasslands, pastures and weedy fields, these vocal, sparrow-like birds have recently arrived from wintering grounds in Central and South America.  They feast on both insects and seeds and will soon pair off and build a nest in the tall grass; 4-6 eggs are generally laid.

As the summer heat builds, dickcissels and other open country birds will dominate the scene as woodland species retreat to the cool shade of forests or riparian groves; already, these tree-dwelling birds are heard more than seen, active behind a dense canopy of leaves.  Throughout the summer months, those hoping to see these birds must arrive early or late in the day, when solar radiation is less intense and cool air settles across the floodplain.

Thursday, May 26, 2016

Mammatus Clouds

As a line of thunderstorms approached Columbia this evening, our daughter called our attention to mammatus clouds above the city.  Indeed, a broad area of dipping lobes was observed overhead, the product of sinking air beneath the advancing cummulonimbus clouds.

Often associated with severe thunderstorms, mammatus clouds (named for their breast-like shape) have long been rumored to predict the development of tornadoes.  However, though their development indicates a potent updraft within the thunderstorm, mammatus clouds are actually most commonly associated with weakening storms.  Nevertheless, they do indicate the presence of wind shear, ice crystals and potent temperature gradients and weather-savvy pilots know to avoid these cloud formations.

For those of us on the ground, mammatus clouds offer a beautiful sight, especially when illuminated by a rising or setting sun; my thanks to Ally for the heads-up!  Fortunately (or unfortunately) we should have more opportunities to observe these clouds this weekend as a potent storm system moves in from the west.

Tuesday, May 24, 2016

A Formal Sendoff

Preparing to leave for Missouri this morning, I heard the distinctive call of an olive-sided flycatcher in the "backyard" of our Littleton, Colorado, farm.  Sure enough, the large-headed silhouette of that summer mountain resident occupied the end of a dead limb; he would intermittently dart out to snare a flying insect before returning to the same perch.  Though formally known as the olive-sided flycatcher, I have long thought he should be called the "tuxedo flycatcher" since his greenish-brown flanks part to reveal a vertical white band on his chest and abdomen.

Passing through the urban corridor on his way to the mountains, this insectivore will spend the summer near forest clearings or along the alpine timberline where he and his mate will aggressively defend their nest (usually placed in a conifer) from all intruders.  Olive-sided flycatchers breed from Alaska to eastern Canada and southward through the Western Mountains and higher stretches of the Appalachians; come September, they will head for wintering grounds in Central and South America.

As for ourselves, we left the farm by early afternoon and enjoyed sunny, mild weather as far east as central Kansas.  There, however, we encountered severe thunderstorms and stopped for the night in Hays, where tornado sirens sent us to the first floor hallway; fortunately, we escaped the brunt of the storms, receiving torrential rain and intense lightening.  Indeed, as I write this post, a spectacular light display continues to our east, promising more stormy weather when we reach Missouri.

Monday, May 23, 2016

A Plumbeous Vireo

During an otherwise unremarkable visit to South Platte Park this morning, I encountered a plumbeous vireo, hunting in shrubs west of Eaglewatch Lake.  Previously grouped with other vireo species under the title "solitary vireo," this gray and white songbird is now classified as a unique species; like all prior members of the group, it has prominent white "spectacles."

Plumbeous vireos breed along the Southern Rockies, from Colorado to Mexico, and across most of the Great Basin.  Primarily insectivores, they move rather slowly among the branches of trees and shrubs, snaring prey from the vegetation; berries are also consumed during the winter months when these songbirds head to coastal regions of Mexico and woodlands of Central America.

True to its former name, this morning's visitor, on his way to mountain forests, was alone.  Unlike many warblers and vireos, his feeding activity was unhurried and methodical, making identification easy in the bright Colorado sunshine.  Perhaps he'll stop by again when chilly September nights invade the Rockies.

Sunday, May 22, 2016

Unwelcome Squatters

Since buying our Littleton, Colorado, farm in 1990, we have often been visited by coyotes; indeed, they killed off our resident foxes several years ago and have lately taken a toll on our cottontail population.  Returning from our trip to California, we noticed that the old fox den beneath our barn had been re-opened and enlarged; we suspected that coyotes had moved in and when coyotes den there is only one reason: pups are expected.

Confirmation was provided yesterday when I observed three coyote pups playing outside the den; how many were inside remains uncertain (6 pups is average).  They will likely be weaned in a week or two and the squatters will move on or simply take up exterior residence on the farm.  We will discourage their stay though they do provide a service when it comes to rodent control; but neighborhood pets, snakes, birds and other wild residents will suffer the consequences of their presence.

We could contact an animal control specialist to trap the squatters but relocation of coyotes is illegal in Colorado so trapping is a death sentence.  Besides, our farm was coyote territory long before we owned it and the dwindling open space in Metro Denver is placing stress on these predators, just as it is on many species of wildlife.  For now, we'll enjoy watching the pups while making sure that mom and dad get the message to move on as soon as possible.

Saturday, May 21, 2016

Visitor from the Desert Southwest

On my usual birding walk at South Platte Park this morning, sightings were unremarkable except for a large number of yellow warblers and the presence of an ash-throated flycatcher.  The latter bird, rare along the Colorado Front Range, is a summer resident of the Desert Southwest, from western Colorado to California and from the northern Great Basin to Mexico.

Unlike most flycatchers, ash-throats generally snare their prey from foliage or directly on the ground; large insects, such as beetles and grasshoppers, are favored but they also consume berries and small lizards.  Nests are placed in the cavities of trees, fenceposts or nest boxes and two broods are raised each year.  Wandering widely during migrations, ash-throated flycatchers sometimes turn up on the East Coast; most winter in coastal regions of Mexico and Central America.

This morning's visitor was feeding on a wooded hillside, west of Eaglewatch Lake; on their home summer range, they are best found in pinyon-juniper or mesquite woodlands, along desert streams or in the canyons of desert ranges.  Adapting well to human habitation, ash-throated flycatchers are gradually expanding their territory and may soon be more common along the Front Range.

Friday, May 20, 2016

The White-tailed Kite

One of the highlights of our recent trip to California was our first sighting of a white-tailed kite, at Humboldt Bay National Wildlife Refuge, just south of Eureka.  Perched in a small grove of trees amidst an extensive wetland, the kite resembled a snowy owl (though out of place and out of season).

White-tailed kites are permanent residents of wooded grasslands and marshlands along the Pacific Coast (from Oregon to Baja), in southern Texas, in southernmost Florida and throughout Mexico, Central America and South America.  Formerly known as the black-shouldered kite, this light-colored raptor often hovers while hunting; small rodents are its favored prey but it also consumes snakes, lizards, frogs and large insects.  Breeding pairs generally produce four offspring each year and the population and range of these beautiful predators appears to be expanding.

It's one thing for a seasoned birder to discover a new life species by patiently stalking small songbirds in dense vegetation and quite another to be confronted by a theretofore unseen raptor, sitting in the open for all to see.  It was as if nature was extending a gift, a reward of sorts for years of enduring stiff necks, cold feet, insect bites and other maladies common to birders.  The gift was sincerely appreciated.

Wednesday, May 18, 2016

Through Riverless Terrain

Leaving Ely, Nevada, this morning, we headed east on US 50; our first stop was Great Basin National Park, in the Snake Range, just west of the Utah Border; details regarding the Park are provided in the linked post.  Today, a deep snow pack closed the Wheeler Peak road at Mather Overlook (just above 9000 feet) but we enjoyed broad views of the Park and adjacent landscape.  We then took a hike along South Baker Creek before setting out across the beautiful but arid lands of the Great Basin.

One of the highlights of that journey was the vast but dry bed of Sevier Lake; filled to the brim during the cool, wet climate of the Pleistocene, the lake is now a sink, fed by the fickle flow of several basin rivers that have been mostly dammed or diverted.  After crossing Interstate 15, we climbed along US 50 to merge with Interstate 70 and then crossed the massive hump of the Wasatch Plateau; beyond this high ridge the highway winds through some of the most scenic topography in North America (if not on the planet) where eroded beds of late Paleozoic and Mesozoic sedimentary rocks line the road.  After dropping through the Waterpocket Fold, we crossed the Green River, completing our loop through Utah, Nevada and California.

Looking down at that River, it occurred to me that this tributary of the Colorado was the first stream of any size that we had crossed since leaving Mono Lake; indeed, the West Fork of the Walker River, north of that lake was the last river that I had encountered.  Such is the nature of the Great Basin: two days of driving through magnificent but riverless terrain.

Tuesday, May 17, 2016

Back in the Basin

Since the high passes through the Sierra Nevada remain closed due to a heavy snowpack, downed trees and rock slides, we backtracked to U.S. 50 last evening and spent the night in Carson City, Nevada.  This morning, we traveled south on Route 395, along the eastern base of the mountains, headed for Mono Lake; approaching that famous remnant of the Pleistocene, we re-entered California, ascended along the West Fork of the Walker River, descended into the basin of Bridgeport Reservoir and then climbed onto the northern rim of the Mono Lake basin where we enjoyed a fabulous panorama of the lake and its surroundings.  For more details on the lake and its history, see the above link.

Stopping at the Visitor Center and three public access sites along the edge of the lake, we explored the tufa (calcium carbonate) formations and surveyed the open waters where thousands of eared grebes fed on brine shrimp; during the autumn migration, up to 1.8 million of these diving birds stop to rest and feed on Mono Lake.  Two pair of ospreys are currently nesting on the tufa formations but must travel to other regional lakes to catch fish, which cannot survive in the alkaline waters of Mono.  Other sightings included hundreds of California gulls and a single pair of ruddy ducks; according to local birders that we met, avocets, black-necked stilts and phalaropes, regular migrants and summer residents at Mono Lake, have not yet arrived.

Heading east across the Great Basin, we passed the northern end of the magnificent White Mountains; Boundary Peak, the highest point in Nevada, is at the northeast end of that Range.  Continuing along U.S. 6, we crossed the stark beauty of of central Nevada; the highlight proved to be the broad, scenic Railroad Valley, southwest of Ely, where Blue Eagle Peak rises along its eastern rim and Currant Mountain anchors its northern end.  After a night in Ely, we plan to visit Great Basin National Park and then head for Colorado.

Monday, May 16, 2016

Assault on Yosemite

As we left Oakdale, California, this morning and headed east on Route 120, the high peaks of the Sierra Nevada shimmered across the eastern horizon, partly obscured by clouds.  Leaving the flat landscape of the Central Valley, we climbed through hills of grass and oak savanna before ascending more steeply into the Sierra foothills.  Charred forest, damaged by wildfire, was soon encountered along the road, extending into western portions of Yosemite National Park.

When we eventually rounded a curve and Half Dome appeared in the distance, I knew that my dream of visiting Yosemite was finally realized.  Indeed, the Park's spectacular glacial valley, lined by the granite cliffs of El Capitan, Half Dome, North Dome and other well-known summits, drained by the beautiful Merced River and adorned by Bridal Veil Falls, Yosemite Falls and other magnificent cascades, is one of the more inspiring sites on our planet.

Arriving on a Monday morning in mid May, we hoped to escape the summer crowds that descend on Yosemite and many other National Parks.  Alas, the crowds were already there, parked along the roadways, congregating at overlooks and clogging popular trails; we, of course, contributed to the human assault.  One wonders if our population has expanded beyond the point where landscapes as grand as Yosemite National Park cannot withstand the onslaught.  It seems we must significantly curtail access if we are to protect these natural gems (or even to make them worth visiting).

Sunday, May 15, 2016

Point Reyes National Seashore

Southwest of Petaluma, California, the Coast Range mellows into a chain of grass covered hills, traversed without mind-numbing switch-backs.  It was across this scenic landscape that we returned to the Pacific Coast, headed for Point Reyes National Seashore.

More than a peninsula along the California Coast, Point Reyes, like much of Southern California, lies on the Pacific Plate, geologically separated from the North American Plate by the San Andreas Fault; the latter passes below Tomales Bay, the Olema Valley and the Bolinas Lagoon, east of the preserve.  Established in 1962, the National Seashore is a mosaic of public and private lands, home to both the Philip Burton Wilderness Area (established in 1976) and a large swath of cattle ranches that date back to the 1850s; it is also home to a herd of tule elk and harbors the Point Reyes Lighthouse, constructed in 1870.  Renowned as an excellent site for whale watching, the lighthouse point was our first destination this morning; unfortunately, high winds and choppy seas impaired our effort to observe whales.  However, we were entertained by a noisy congregation of elephant seals on Drake Beach and were inspired by spectacular seascapes across the peninsula.

After leaving Point Reyes, we headed for San Francisco, enduring innumerable hairpin turns as we climbed over the Coast Range for a final time.  We then traversed the majestic Golden Gate Bridge, clogged with vehicles and walkers alike on this mild, sunny Sunday and headed for famous attractions along the city's waterfront.  Though we enjoyed a pleasant meal overlooking the Bay, the congestion of San Francisco was hard to take after a week on the road and we set our sights on Yosemite National Park; after a night in the Great Central Valley, we'll head to the Park tomorrow.

Saturday, May 14, 2016

Counting on the Coast

Today was designated Global Big Day by eBird, an effort to assess the health and diversity of avian populations across the planet.  Since we planned a morning visit to Mendocino Coast Botanical Gardens, just south of Fort Bragg, California, I decided to submit my observations from that location.

As we walked through the fabulous gardens, more birds were heard than seen but the wide diversity of foliage attracted an excellent variety of species; in addition, since the gardens extend to cliffs above the Pacific, a number of sea birds were observed.  Highlights of the morning count (which totaled 30 species) included pigeon guillemots, pelagic cormorants, Allen's hummingbird, olive-sided flycatchers, Steller's jays and a large number of white-crowned sparrows.  While my contribution to Global Big Day was modest, I was honored to participate and certainly enjoyed the experience.

South of the Gardens, we visited a magnificent sand dunes ecosystem at Manchester State Park and enjoyed a long, scenic hike to sea cliffs at Salt Point State Park.  Sea fog slowed our journey to Jenner where we turned inland, climbing along the beautiful Russian River; passing through the Coast Range, we escaped the fog and settled in a hotel room along Route 101.  Tomorrow we plan to visit the Point Reyes National Seashore before heading into San Francisco.

Friday, May 13, 2016

A Kite, Whales and a Glass Beach

Early this morning, my wife and I visited the Humboldt Bay NWR, just south of Eureka, California.  Once a vast saltwater marsh, the basin was later drained for agriculture and has since been restored for the benefit of resident and migrant water birds; riparian woodlands, cattail marshes, sloughs, lakes and tidal flats characterize the preserve.  During our visit, we were fortunate to observe a white-tailed kite (formerly known as a black-shouldered kite), a beautiful and common resident of the refuge and a new "lifer" for me; we also encountered black phoebes, California quail and a large flock of marbled godwits.

After our visit to the refuge, we headed south on Route 101, climbing along the scenic valley of the Eel River and its South Fork.  We then switched to Route 1, enduring countless hairpin turns as we crossed the Coastal Range.  Emerging along the Pacific Coast, our patience was rewarded with spectacular seascapes all the way to Fort Bragg.  Nearing that city, we turned into MacKerricher State Park, where we walked out to Seal Point and watched harbor seals as they lounged on the sea stacks or cruised the clear waters beneath the overlook.  While observing the seals, my wife noticed "whale spouts" far out to sea; close inspection with my binoculars revealed four humpback whales, identified by the contour of their backs and by their habit of raising their massive flukes as they dove to feed.  Needless to say, the sighting of these magnificent cetaceans was one of the highlights of our road trip to date.

But we could not end our day without visiting the "Glass Beach," in Fort Bragg.  Once used as a city dump site, the beach was reclaimed by the sea which sorted and recycled the debris, leaving smooth pebbles of glass amidst the shells and sand.  Once this beach of glass gained nationwide fame, visitors flocked to the site, walking off with samples of nature's handiwork.  As too often characterizes man's relationship with nature, we first abuse her ecosystems and then take advantage of her restorative powers; alas, the glass of Glass Beach is rapidly disappearing.

Thursday, May 12, 2016

The Redwood Coast

The Siskiyou Mountains stretch from southwestern Oregon into northwestern California, separating the watershed of the Rogue River (to their north) from that of the Klamath River (to their south).  This morning, we drove northwest from Medford, Oregon, descending through the Rogue River Valley; after crossing the Rogue at Grants Pass, we headed southwest on Route 199, climbing back through its watershed along the Applegate and Illinois Rivers, two of its major tributaries.  Passing through the Collier Tunnel, we left the Rogue River watershed and entered that of the Smith River, which drains the southwestern end of the Siskiyous.

Descending along the Middle Fork of the Smith River, we stopped at the Jedediah Smith Redwoods State Park and explored the Stout Grove, one of the more pristine and scenic stands of redwood forest in California; walking among those giants, their shade supporting a rich understory of ferns, one is both inspired and humbled.  Moving on to Crescent City, we observed massive seabird colonies (mostly common murres) on Castle Rock and visited Point St. George where we encountered ospreys, black oystercatchers, whimbrels, black scoters, brown pelicans and a host of shorebirds; the highlight was provided by a peregrine falcon that swooped down at close range to snare an unwary sandpiper.

Heading south on Highway 101, we encountered herds of Roosevelt elk, drove through more stands of majestic redwoods and stopped at numerous overlooks to scan the ocean for whales, sea birds and sea lions.  While we failed to observe whales on this cool, foggy day, we did find a large colony of noisy pinnipeds, crowding a sea stack near Trinidad.  Tomorrow we continue our journey down the California coast.

Wednesday, May 11, 2016

Exploring Volcanic California

Yesterday morning, we left Lake Tahoe and drove north on Route 89, undulating across the east flank of the Sierra Nevada; initially, all streams (including the scenic Little Truckee River) rumbled eastward, flowing into the Great Basin.  Then, about an hour into our journey, we crossed a fork of the Feather River; its flow was to the west, indicating that we had reached the gap between the Sierra Nevada Range and the Cascades.  After lunch in Quincy, California, we climbed along Indian Creek and then Wolf Creek, eventually reaching Lake Almanor, east of Lassen Peak.

Though we had planned to hike at Lassen National Park, we soon learned that the Park road was closed due to a heavy snowpack.  We thus visited McArthur-Burney Falls Memorial State Park, off Route 89; there we enjoyed the scenic falls and hiked through a gorge of volcanic basalt.  Another detour, resulting from a snow-blocked National Forest road, sent us westward, where we circled the majestic cone of Mt. Shasta.  Angling northeast on Route 97, we then crossed tule marshes and the Butte Valley Grasslands, passed through Klamath Falls, Oregon, and dipped back into California, spending the night in Tulelake.

This morning, we visited the fabulous Tule Lake NWR, where we encountered American white pelicans, western grebes, eared grebes, bald eagles, a few sandhill cranes, cormorants, various terns and a wide variety of waterfowl (including cinnamon teal).  We then visited Lava Beds National Monument, just northeast of the dormant Medicine Lake volcano, where we explored basalt flows and lava tubes.  Finally, we passed through Lower Klamath NWR (where avocets were especially abundant) and drove west to Medford, Oregon, dropping through the scenic Siskiyou Mountains en route.  Tomorrow we head for the California Coast.

Monday, May 9, 2016

Crossing the Great Basin

West of Salt Lake City, Interstate 80 passes between the north end of the Oquirrh Range and the Great Salt Lake.  As we drove west, black-necked stilts were feeding in the roadside shallows, cliff swallows swooped about the highway bridges and flocks of California gulls moved across the morning sky.  Throughout western Utah, flat plains, remnants of Lake Bonneville, alternated with stark fault-block ranges, many of which were capped with snow.

In eastern Nevada, the ranges were more numerous and the intervening valleys were both rolling and green, covered by sage grasslands that were grazed by horses, cattle and pronghorn.  Just west of Wells, the highway began to follow the Humboldt River, passing the majestic Ruby Mountains; we would parallel that river all the way to Lovelock, where it enters its terminal sink.  Beyond that point, the greenery of eastern Nevada gave way to desert landscape, characterized by vast lake flats where American avocets patrolled the alkaline pools.  This low desert, lying within the rain shadow of the Sierra Nevada, ended at Fernley where we climbed into the Sierra foothills along the Truckee River.  Passing through Reno, we continued westward and upward on Interstate 80 before turning south to Lake Tahoe.

Backed by the high spine of the Sierra Nevada, this beautiful lake is renowned for both its resorts and its fabulous alpine scenery; after a full day on the road,  it seemed like a great place to spend the night.  Tomorrow we head into the California Cascades.

Sunday, May 8, 2016

From Denver to Salt Lake

Beginning the first leg of our California road trip, we left Denver this morning, headed west on Interstate 70.  Climbing through the Front Range, we crossed the Continental Divide at the Eisenhower Tunnel and entered the vast watershed of the Colorado River.  After dipping through the Blue River Valley, we crossed Vail Pass and descended along Gore Creek and the Eagle River to the Colorado itself.

Following the Colorado, we snaked down Glenwood Canyon and, just west of Glenwood Springs, cut through the Grand Hogback, entering the Colorado Plateau, a landscape of mesas, buttes, plateaus and cliff-lined valleys.  Passing Battlement and Grand Mesas to our south and the Roan Plateau to our north, we then drove along the Book Cliffs (Cretaceous in age), that rise along the north side of the Interstate from Grand Junction to Green River, Utah.  Leaving the Colorado, we entered Utah where the La Sal Mountains, a massive laccolith near Moab, loomed to the SSW; after crossing the Green River, just east of the Waterpocket Fold, we turned north on US 6 toward Price, Utah, passing formations of Mancos Shale carved by the Price River and its tributaries.

Beyond Price, the highway climbs onto the Wasatch Plateau where, at Soldier Summit (7477 feet), we left the watershed of the Colorado River and entered the Great Basin, dropping from the Plateau and through the Wasatch Range to the urban corridor of Provo and Salt Lake City.  Tomorrow, we cross the Great Basin on Interstate 80, headed for Reno and Lake Tahoe.

Saturday, May 7, 2016

Birding in Bad Weather

Since we are leaving on our California road trip tomorrow, I decided to get in one more visit to South Platte Park.  While recent visits to the preserve occurred on warm, sunny days, this morning promised a different experience; low clouds, chilly air and a steady northeast breeze greeted me at the parking lot.

Despite these conditions (and, indeed, because of them), birding was excellent at the floodplain refuge.  Violent-green swallows were especially abundant, strafing the lakes and the woodlands; other sightings of note included 55 yellow-rumped warblers, 17 yellow warblers, 6 yellow-breasted chats, 4 western tanagers, a few chipping sparrows and a lone great horned owl that stared at me from a lakeside tree.  In all, my two-mile walk turned up 33 species, better than my counts on the warm, sunny days.

A gray overcast produces lighting that mimics dawn and dusk, when many species tend to be most active.  In addition, the chilly air invigorates birds and mammals alike, stoking the drive to move and to feed.  As a consequence, birding is often most productive on days that are less appealing to birders; today's visit to South Platte Park reinforced that fact.

Friday, May 6, 2016

The Cormorant Doth Soar!

Reading out back yesterday afternoon, I looked up to see a dark bird soaring high above our Littleton farm.  Since similar past sightings turned out to be a golden eagle or a Swainson's hawk, I grabbed my binoculars for a closer look.  To my surprise, the aerialist was a double-crested cormorant and his circular flight, with no apparent destination, continued for twenty minutes.

Usually observed flying low at rapid speed (when not resting on limbs, docks or channel markers or diving for fish in bays or lakes) cormorants are not generally included on a list of soaring birds; members of that group include eagles, vultures, cranes, buteos, kites, frigatebirds, gulls, pelicans and albatrosses, among others.

Indeed, often maligned as a "fish crow," the cormorant is not a stately bird.  Perhaps, like many humans, yesterday's high flier needed to boost his self esteem; mimicking a golden eagle is certainly one way to achieve that goal!  Then again, if you're equipped with wings and have the ability to soar high above scenic Colorado on a beautiful spring day, why not?

Thursday, May 5, 2016

An Ibis Squadron

Returning to South Platte Park this morning, I found that the yellow-rumped warbler invasion had diminished but those active insectivores were still abundant in the trees surrounding Eaglewatch Lake; my official count today was 93, less than a third of my estimate two days ago.  Joining them were an increasing number of summer residents (especially house wrens and yellow warblers) and the usual mix of late spring visitors.  A flock of American white pelicans soared above the refuge, an osprey fished on the open waters and the last of the wintering ducks had apparently left for northern breeding grounds.

This morning's highlight was a squadron of 16 white-faced ibis, moving in tight formation from southwest to northeast.  Having wintered in Mexico or along the Gulf coast, these western ibis are on their way to shallow wetlands across the Northern Plains, stopping to rest and feed on small fish and aquatic invertebrates en route; they generally appear along the Front Range in late April or early May.

Engrossed as I was with counting songbirds on the meadows and in the trees, the appearance of the ibis was both a pleasant diversion and an inspiring sight.  Like the flocks of migrant geese in spring and fall, they evoke a spirit of freedom that most humans can only begin to appreciate.

Tuesday, May 3, 2016

Invasion of Yellow-Rumped Warblers

Hoping that my second e-Bird checklist for South Platte Park would significantly exceed my first (see A Disappointing Survey), I headed down to the floodplain refuge on this cool, sunny morning.  Taking my usual 2-mile loop hike, I encountered 30 species, a modest improvement from last month; however, the count included two ospreys, a flock of Franklin's gulls, a tardy group of female buffleheads, a lone loggerhead shrike and a flock of 17 barn swallows, perched in a small tree and presumably exhausted from their migration.

But the highlight of this visit was a tremendous number of yellow-rumped warblers (I estimated 300), foraging in almost every tree that graces the southern section of the refuge.  Indeed, their numbers were so great that the movement of these small insectivores distracted me from other species that I attempted to locate.  Per records provided on e-Bird, this count is more than double the previous maximum for any site in Colorado this year but it doesn't come close to the U.S. e-Bird record of 63,600+ observed at Cape May, New Jersey in the autumn of 2010.

After wintering across most of the central and southern latitudes of the U.S. and Mexico, yellow-rumped warblers return to breeding areas in the western mountains of North America and across Alaska, Canada and northernmost regions of the Lower 48.  During their spring and fall migrations, they often travel in large flocks, a fact that was certainly confirmed at South Platte Park this morning.