Sunday, November 24, 2013

Wood Stork

Wood Stork

Mycteria americana
Photo: Wood stork in water
Wood storks fish with an unusual but effective method: Opening their bills underwater, they wait for a fish to pass by, then snap!, like a mousetrap, the bill is closed, and the fish is eaten.
Photograph by Joel Sartore
Wood storks are tall, white denizens of freshwater or brackish wetlands and swamps. They can be identified by their long legs, featherless heads, and prominent bills.
These waders feed on minnows in shallow water by using their bills to perform a rare and effective fishing technique. The stork opens its bill and sticks it into the water, then waits for the touch of an unfortunate fish that wanders too close. When it feels a fish, the stork can snap its bill shut in as little as 25 milliseconds—an incredibly quick reaction time matched by few other vertebrates.
The storks prefer to employ this technique in isolated pools created by tides or falling freshwater levels, where fish congregate en masse. In some areas, such as Florida, breeding begins with the dry season that produces these optimal fishing conditions.
Though wood storks eat small fish, they eat a lot of them. An average nesting pair, with two fledglings, may eat over 400 pounds (181 kilograms) of fish during a single breeding season.
Wood storks are social animals. They feed in flocks and nest in large rookeries—sometimes several pairs to a single tree. Females lay two to five eggs, which both sexes incubate for about one month. Young fledge about two months after hatching.

Wednesday, November 13, 2013

Wild Turkey

Wild Turkey

Meleagris gallopavo
Photo: A wild turkey
Wild turkeys, with their distinctive feathers and gobbling call, were Benjamin Franklin's choice for the national bird of the United States.
Photograph courtesy Gary M. Stolz/U.S. Fish and Wildlife Service
The turkey was Benjamin Franklin's choice for the United States's national bird. The noble fowl was a favored food of Native Americans. When Europeans arrived, they made it one of only two domestic birds native to the Americas—the Muscovy duck shares the distinction.
Yet by the early 20th century, wild turkeys no longer roamed over much of their traditional range. They had been wiped out by hunting and the disappearance of their favored woodland habitat.
Wild turkeys typically forage on forest floors, but can also be found in grasslands and swamps. They feed on nuts, seeds, fruits, insects, and salamanders.
Wild turkey reintroduction programs began in the 1940s, and the birds were relocated to areas where populations had been decimated but woodlands were recovering. Such efforts worked so well that wild turkeys now live in areas where they may not have occurred when Europeans first reached the Americas. Today, flocks are also found in Hawaii, Europe, and New Zealand.
Only male turkeys display the ruffled feathers, fanlike tail, bare head, and bright beard commonly associated with these birds. They also gobble with a distinctive sound that can be heard a mile (a kilometer and a half) away.
Females lay 4 to 17 eggs, and feed their chicks after they hatch—but only for a few days. Young turkeys quickly learn to fend for themselves as part of mother/child flocks that can include dozens of animals. Males take no role in the care of young turkeys.
Domestic turkeys have white-tipped tails because they are the descendants of a Mexican subspecies that was taken to Europe for domestication in the early 16th century. The feature distinguishes them from most modern wild turkeys, though captive diet, lifestyle, and breeding have caused other physical discrepancies.

Sunday, October 6, 2013

Prehistoric Elephant-Spork for mouth

Absurd Creature of the Week: This Prehistoric Elephant Had a Huge Spork for a Mouth

Russian writer Anton Chekhov insisted that everything irrelevant to a work of fiction be removed — if you describe a rifle mounted on the wall, someone had better fire it off at some point. This dramatic principle is called Chekhov’s gun, and it actually applies quite well to the natural world: Animals don’t waste energy developing worthless characteristics. Traits that help a species survive get passed along through generations, while those that are no longer useful fade away (or in the stubbornly contrary case of the human appendix, abruptly explode).
Platybelodon’s remarkable modified tusks. Image: American Museum of Natural History, via the Biodiversity Heritage Library








If Chekhov had time-traveled back between 8 million and 20 million years and met Platybelodon — an ancestor of the modern elephant that looked like it got hit in the face with a shovel, then absorbed that shovel into its mouth — he would have demanded the creature explain itself. What possible purpose could such a ridiculous trait serve? “A good one, thank you very much,” Platybelodon would reply, probably in a really funny voice.
The spork-faced Platybelodon’s strange jutting jaw actually consists of a second pair of flattened, widened tusks (tusks themselves being modified incisors). When the genusPlatybelodon, which means “flat tooth,” and its species were first described in the 1920s, “their lower incisors were thought to function to shovel, scoop, dig and dredge soft vegetation in aquatic or swampy environments,” vertebrate paleontologist William Sanders of the University of Michigan wrote in an email to WIRED. “But recent analysis of tusk wear surfaces show that they were used more as scythes to cut tough vegetation.”
The paleontologist who proposed this slicing behavior in 1992, David Lambert, theorized that instead of roaming shorelines, Platybelodon fed on terrestrial plants, grasping branches with its trunk and cutting them away with its built-in scythe. Indeed, cross-sections of the tusks reveal a structure that provides extra strength and resistance to abrasion for such foraging, said Sanders.
So it could well be that Platybelodon wandered around Miocene Asia, Africa, and North America, scything vegetation like some sort of peasant, only without all the pesky class struggles. And it was just one of a horde of similar animals in the family Gomphotheriidae, all with modified lower tusks of varying styles. The Platybelodon genus alone had more than 15 species, reaching “the apex of development of these lower tusks,” according to Sanders. Their radically flattened teeth suggest “strong selection for specialized feeding on a particular range of plants,” which was crucial given that “for much of the Miocene there were often three to five or more genera of proboscideans occurring in the same landscape, competing for forage.”
Pegging the various appearances of such proboscideans, though, is difficult, because flesh-like schnozes don’t fossilize as easily as bone. We’re actually quite lucky to have Platybelodon preserved at all, considering that fossilization is a really hard thing to pull off. Even if you can avoid getting carted off in a dozen different directions by scavengers, you need to settle in the right spot. And Platybelodon just so happened to do us a solid by dying — sometimes en masse — next to or in rivers, the prime locales for fossilization.
Osborn’s reconstruction of Platybelodon from his 1936 book Proboscidea. Males sported larger scythes than females — an example of sexual dimorphismImage: American Museum of Natural History, via the Biodiversity Heritage Library
Henry Fairfield Osborn, a paleontologist who described Platybelodon in a 1932 paper and quite extensively four years later in his book Proboscidea, accordingly assumed the creature to be a water-dredger (thanks to the work of Lambert and others we now believe that Platybelodon, like a lot of animals, was probably just partial to water and happened to sometimes die in it). In his book, Osborn quoted another paleontologist, Alexei Borissiak, who in 1929 wrote that Platybelodon was “deprived of a trunk” but would scoop through the water and “seize its food with its muscular upper lip, covering the mandible.” In fact, Borissiak reckoned Platybelodon’s snout looked a bit like that of the hippopotamus, “although much more lengthened out.” Osborn’s illustrations of Platybelodon certainly reflect this.
But “think about what an elephant looks like,” Sanders asks us. “The trunk is a very separate entity from the mouth. You have to be able to get food into your mouth, and if your front limbs are occupied in posture, and you have upper and lower tusks that would make it difficult to have a long projecting tongue or mobile lips, then you need a proboscis.”
A model of Platybelodon featuring a dexterous proboscis, in keeping with Lambert’s grab-and-slash theory. Image: Wikimedia







“[Osborn's] ego preceded his expertise,” he added, “and we are still digging out from the weight of his ‘authority’ on proboscideans.” Yet Osborn’s flat trunk/lip persists in most modern reconstructions — including an oh-so-close-to-actually-being-cute one in the Ice Age movies — conflicting with Lambert’s more widely accepted grab-and-scythe theory.
Trunks aside, could the bizarre mug ofPlatybelodon, so wonderfully adapted for feeding, have proved cumbersome when, say, fleeing from predators? Sanders doesn’t think so. And even ifPlatybelodon did face-plant here and there, its size would have proved quite the advantage as far as not getting eaten goes. It was somewhat smaller than the modern African elephant, which only rarelyfalls prey to that continent’s apex predator, the lion. But according to Sanders, Platybelodon might have had a counterpart predator in the ferocious wolf-like creodonts, meaning “flesh tooth,” meaning a slicing tooth designed to deprive you of flesh, meaning let’s be grateful it was Platybelodon worrying about them and not us.
So be they teeth like scissors or teeth like a shovel, evolution never creates a rifle it doesn’t intend to fire. Where fiction has Chekhov’s gun, nature has Platybelodon’s giant spork.

Saturday, September 28, 2013

Whooping Crane

Whooping Crane 

Grus americana
Photo: Whooping crane standing in water
Back from the brink of extinction, the endangered whooping crane is making a slow recovery. Only about 200 are currently living in the wild.
Photograph courtesy Luther Goldman/U.S. Fish and Wildlife Service
Whooping cranes nearly vanished in the mid-20th century, with a 1941 count finding only 16 living birds. But since then, these endangered animals have taken a step back from the brink of extinction. Captive breeding programs have boosted their numbers, and successful reintroduction efforts have raised the number of wild birds to over 200, with roughly the same number living in captivity.
The massive whooping crane management effort involves numerous U.S. and Canadian governmental agencies, nonprofit organizations, volunteers, and other contributors. The process even includes using ultralight aircraft to lead young whooping cranes on their first southward migration, from Wisconsin to Florida.
These majestic white birds are the tallest in North America. They live in family groups and frequent marshes, shallow lakes, and lagoons. Cranes feed by foraging with their bills and gobbling up plants, shellfish, insects, fish, and frogs.
The whooping crane's primary natural breeding ground is Wood Buffalo National Park, in Canada's Northwest Territories and Alberta. Here the cranes perform elaborate running, leaping, wing-flapping dances to choose mates that they will keep for life.
When summer ends, these migratory birds set out for the Gulf Coast of Texas, where they winter in the Aransas National Wildlife Refuge. Managers hope to establish a Wisconsin breeding population that will winter in Florida, where a small introduced population lives year-round on the Kissimmee Prairie.
Whooping cranes are generally safe from hunting and egg collection, which hastened their decline. However, their biggest threat—loss of wetlands—persists. Though the areas that the birds frequent are protected, they are isolated and make the entire population vulnerable to any disastrous ecological event or change.

Ostrich

Ostrich

Struthio camelus
Photo: Portrait of an ostrich
Portrait of an ostrich
Photograph by Carsten Peter
The flightless ostrich is the world's largest bird. They roam African savanna and desert lands and get most of their water from the plants they eat.
Though they cannot fly, ostriches are fleet, strong runners. They can sprint up to 43 miles (70 kilometers) an hour and run over distance at 31 miles (50 kilometers) an hour. They may use their wings as "rudders" to help them change direction while running. An ostrich's powerful, long legs can cover 10 to 16 feet (3 to 5 meters) in a single stride. These legs can also be formidable weapons. Ostrich kicks can kill a human or a potential predator like a lion. Each two-toed foot has a long, sharp claw.
Ostriches live in small herds that typically contain less than a dozen birds. Alpha males maintain these herds, and mate with the group's dominant hen. The male sometimes mates with others in the group, and wandering males may also mate with lesser hens. All of the group's hens place their eggs in the dominant hen's nest—though her own are given the prominent center place. The dominant hen and male take turns incubating the giant eggs, each one of which weighs as much as two dozen chicken eggs.
Contrary to popular belief, ostriches do not bury their heads in the sand. The old saw probably originates with one of the bird's defensive behaviors. At the approach of trouble, ostriches will lie low and press their long necks to the ground in an attempt to become less visible. Their plumage blends well with sandy soil and, from a distance, gives the appearance that they have buried their heads in the sand.
Ostriches typically eat plants, roots, and seeds but will also eat insects, lizards, or other creatures available in their sometimes harsh habitat.

Friday, September 20, 2013

Carolina Wren

Carolina Wren 

Thryothorus ludovicianus

Photo: A Carolina wren
Favoring warmer southern climates, the Carolina wren—the state bird of South Carolina—fills its habitat with sweet songs.
Photograph by Mark Chappell/Animals Animals—Earth Scenes
The Carolina wren is an adaptable dweller of forestlands, swamps, farms, and tree-filled human communities.
Carolina wrens (Thryothorus ludovicianus) are small but very vocal animals. Males are especially outgoing and are the only ones to produce songs. They employ one of the loudest songs per volume of birds. They are apt to sing anytime and anyplace they happen to be.
Carolina wrens are usually found in pairs, and each pair stays on its home territory all year long. Because these wrens cannot survive cold winters, they tend to live in southern climes, and are the official state bird of South Carolina. They are found as far north as the Great Lakes, and warm winters spur them to extend their range northward. However, when colder years arrive, many northern birds are unable to survive and fringe populations plummet.
These large wrens feed on insects, larvae, and spiders but also eat berries and fruit. They forage on or near the ground and hop along far more often than they fly. They use their bills to poke about and search for hidden meals and try to remain close to brush in which they can hide.
Carolina wrens are monogamous, and breeding pairs may stay together for years. They work together to construct nests—which may be found almost anywhere. Wrens nest in natural locations such as branches, tree-holes, and stumps but also frequent windowsills, mailboxes or other attractive human-made spots.
Females lay about four eggs and incubate them for two weeks while their mates bring them food. Both parents feed their chicks for an additional two weeks before they gain independence. A mating pair of Carolina wrens may have several broods each year.
Read full here...

Saturday, June 22, 2013

Tundra Swan

Tundra Swan


Cygnus columbianus
Photo: Tundra swan swimming in water
The graceful tundra swan feeds not only on underwater flora and shellfish but has developed a taste for grains and corn, much to the chagrin of farmers.
Photograph by Bates Littlehales
The snowy white tundra swan breeds in the Arctic and migrates many miles to winter on North America's Atlantic and Pacific coastlines, bays, and lakes. The eastern population frequents the Chesapeake Bay and North Carolina, while the western population typically winters in California. These animals fly some 3,725 miles (6,000 kilometers) round-trip between their distant habitats, and make the daunting journey twice each year. Tundra swan subspecies also winter in Europe and Asia.
Tundra swans are often confused with trumpeter swans, and indeed the two species are very similar in appearance. They are most easily distinguished by their calls.
Tundra swans winter on the water and sleep afloat. They are strong and speedy swimmers that take to the air with a running start, clattering across the water's surface with wings beating. In flight, the rhythmic flapping of the swan's wings produces a tone that once earned it the name "whistling swan."
These large birds feed by dipping their heads underwater to pluck aquatic plants, tubers, and roots. They also eat shellfish and are developing an increasing taste for grains and corn found in farmland areas.
Believed to mate for life, these swans actually pair up for nearly an entire year before breeding. Though in their winter grounds they gather in huge flocks, they breed as solitary pairs spread out across the tundra. Each couple defends a territory of about three-fourths square miles (two square kilometers).
The bird's tundra nests are large stick dwellings lined with moss and grasses. Ideally, they are situated close to a pond or other water source.
Females typically lay about four eggs and incubate them for 32 days while males guard the nest. Young chicks are protected from cold and predators, including swarms of voracious Arctic mosquitoes. Tundra swans can be nasty when aroused, and the birds may even be able to fend off predators like foxes and jaegers.

Friday, June 21, 2013

Osprey

Osprey 

Pandion haliaetus
Photo: An osprey preparing to dive
An osprey preparing to dive
Photograph courtesy NASA
Ospreys are superb fishers and indeed eat little else—fish make up some 99 percent of their diet. Because of this appetite, these birds can be found near ponds, rivers, lakes, and coastal waterways around the world. Ospreys hunt by diving to the water's surface from some 30 to 100 feet (9 to 30 meters) up. They have gripping pads on their feet to help them pluck fish from the water with their curved claws and carry them for great distances. In flight, ospreys will orient the fish headfirst to ease wind resistance.
Ospreys are sometimes confused with bald eagles, but can be identified by their white underparts. Their white heads also have a distinctive black eyestripe that goes down the side of their faces. Eagles and ospreys frequent similar habitats and sometimes battle for food. Eagles often force osprey to drop fish that they have caught and steal them in midair.
Human habitat is sometimes an aid to the osprey. The birds happily build large stick-and-sod nests on telephone poles, channel markers, and other such locations. Artificial nesting platforms are common in areas where preservationists are working to reestablish the birds. North American osprey populations became endangered in the 1950s due to chemical pollutants such as DDT, which thinned their eggshells and hampered reproduction. Ospreys have rebounded significantly in recent decades, though they remain scarce in some locales.

Saturday, May 18, 2013

Cardinal


Cardinal


Cardinalis cardinalis


Photo: Cardinal in tree with snow
Noted for their bright red plumage, cardinals have about two dozen songs.
Photograph courtesy Harvey Doerksen/U.S. Fish and Wildlife Service
The northern cardinal is so well loved that it has been named the official bird of no fewer than seven U.S. states. Bright red cardinals are easily identified by even casual bird watchers, and are often seen frequenting backyards and bird feeders. When foraging elsewhere the birds eat insects, seeds, grain, fruit, and sap.
Cardinals, also called "redbirds," do not migrate and have traditionally been more common in warmer climes such as the U.S. southeast. However, in recent decades they have expanded their common range north through the United States and even into Canada. This population growth may be due to an increase in winter birdfeeders and to the bird's ability to adapt to parks and suburban human habitats.
Only males sport the brilliant red plumage for which their species is known. The color is a key to mating success—the brighter the better. Females are an attractive tan/gray.
Cardinals are active songbirds and sing a variety of different melodies.
Males can be aggressive when defending their territory, and they frequently attack other males who intrude. This tendency sometimes leads cardinals to fly into glass windows, when they charge an "intruding bird" that is really their own reflection.
Does't look like an Angry Bird?


Friday, May 3, 2013

Toucan


Toucan

 
Ramphastos toco


Photo: Profile of a toucan
The toucan's large, colorful bill may look like it packs a bite, but it is better adapted for feeding than fighting.
Photograph by Jason Edwards
The Toco toucan is at home in South America's tropical forests but recognized everywhere. The toucan's oversized, colorful bill has made it one of the world's most popular birds.
The 7.5-inch-long (19-centimeter-long) bill may be seen as a desirable mating trait, but if so, it is one that both male and female toucans possess. In fact, both sexes use their bills to catch tasty morsels and pitch them to one another during a mating ritual fruit toss.
As a weapon, the bill is a bit more show than substance. It is a honeycomb of bone that actually contains a lot of air. While its size may deter predators, it is of little use in combating them.
But the toucan's bill is useful as a feeding tool. The birds use them to reach fruit on branches that are too small to support their weight, and also to skin their pickings. In addition to fruit, Toco toucans eat insects and, sometimes, young birds, eggs, or lizards.
Toco toucans live in small flocks of about six birds. Their bright colors actually provide good camouflage in the dappled light of the rain forest canopy. However, the birds commonly keep up a racket of vocalization, which suggests that they are not trying to remain hidden.
Toucans nest in tree holes. They usually have two to four eggs each year, which both parents care for. Young toucans do not have a large bill at birth—it grows as they develop and does not become full size for several months.


Thursday, April 25, 2013

Thick-Billed Murre


Thick-Billed Murre

 
Uria lomvia


Photo: Murres atop a rock
Thick-billed and thin-billed murres rest on a rock in the sun on Gull Island in Alaska. Thick-bills are recognizable not just by their slightly heavier bills but also by the white line down the sides of the bill.
Photograph by Michael Melford
The thick-billed murre swims far better than it flies. Takeoff is awkward, but once it's airborne, it can fly at about 75 miles an hour (120 kilometers an hour). Among the deepest underwater divers of all birds, it uses its stubby wings to "fly" through the water, routinely reaching depths of more than 330 feet (100 meters)—sometimes even twice that—in pursuit of the fish, squid, and crustaceans it feeds on.
Covered in black feathers on its head, back, and wings and white feathers on its breast and underside, this waterbird can be found in and around Arctic waters. In the summer it breeds off the rocky coasts of Alaska, Canada, Greenland, Scandinavia, and Russia. But in winter—when it's not breeding—the thick-billed murre is at sea, off the edge of open ice southward to Nova Scotia and northern British Columbia. It also winters off the coasts of Greenland, northern Europe, and southward in the Pacific Ocean to northern Japan.
The thick-billed murre doesn’t build nests. Instead, the female joins others of her species in a large, noisy colony and lays a single egg on a narrow cliff ledge. She then arranges pebbles and other debris close to the egg, cementing them with feces to form a support that prevents the large egg from rolling off the ledge if it dislodges. The egg hatches in 30 to 35 days. Both parents feed the chick, caring for it until it fledges at about 21 days old. At this time, chicks make a migratory journey that is unique among birds, swimming as far as 620 miles (1,000 kilometers) in the first leg to their wintering grounds off the coast of Newfoundland.


Friday, April 19, 2013

Canvasback


Canvasback

 
Aythya valisineria


canvasback-diver-duck.jpg
Canvasbacks are diver ducks well equipped with their own form of flippers—large webbed feet that make them smooth and graceful swimmers.
Photograph by Jac6.Flickr, Flickr
Canvasbacks are diver ducks well equipped with their own form of flippers—large webbed feet that make them smooth and graceful swimmers. They spend much of their time in the water and use their long bills to feed by digging through bottom sediments in search of aquatic plant stems and roots, or submerged insects, crustaceans, and clams.
On land, canvasback movements are clumsy and the ducks seldom stray too far from the water’s edge. But when “cans” take to the air they can cover a lot of ground.
Each year when winter weather begins to chill northern lakes, ponds, and prairie wetlands, the canvasbacks’ food becomes scarce and the ducks take flight in enormous flocks. Thousands of birds migrate together each year to traditional wintering sites like the Chesapeake Bay, San Francisco Bay, Gulf Coast, and Mexico. The majority of North American canvasbacks breed in the Prairie Pothole wetlands and migrate via the Mississippi Flyway to the Mid-Atlantic and Lower Mississippi Alluvial Valley, or along the Pacific Flyway to the California coast.
The Chesapeake Bay’s Susquehanna Flats area was once the winter home of perhaps half of the North American canvasback population. But the shoals’ lush beds of wild celery have declined with compromised water quality and increased sedimentation. Chesapeake canvasback numbers followed suit and have declined some 80 percent over the last 50 years.


Wednesday, April 17, 2013

Steller's Sea Eagle


Steller's Sea Eagle

 
Haliaeetus pelagicus

Photo: Steller's sea eagle on snow spreading wings
Holding its prey down with powerful talons, a Steller's sea eagle displays its wings, which can have a span of over 6 feet (2 meters).
Photograph by Tim Laman
These very large, powerful eagles are also striking in appearance. They are dark but dramatically colored with white tail, shoulders, rump, thighs and forehead.
These eagles are believed to breed only in far eastern Russia, along the coasts and surrounding islands of the Sea of Okhotsk and Bering Sea. They are most common on the Kamchatka Peninsula.
Each winter, many Steller's sea eagles migrate from their breeding grounds to Japan, and a few reach Korea or even farther afield. Other individuals do not migrate, but simply move to open water as winter approaches.
Open water provides these eagles with their main food sources along coastlines and lakes. In their breeding grounds, Steller's sea eagles subsist largely on salmon, and they both hunt and scavenge for this resource. Annual salmon runs provide an enormous bounty and Steller's sea eagle nests are typically located near coasts and rivers where these fish appear en masse.
These birds of prey hunt from a perch or from flight by diving and clutching prey in their talons. They also stand in shallow water or on the ice and grab passing fish when the opportunity arises. Like other eagles, Steller's also steal food from other birds.
In Japan, Steller's sea eagles feast on cod. In addition to fish, they eat crabs, shellfish, squid, small animals, ducks, gulls, and carrion.

Monday, April 8, 2013

Mallard Duck


Mallard Duck

 
Anas platyrhynchos


Photo: A mallard duck
Male mallards, or drakes, are more distinctively colored than females, who are mottled brown with a flourish of iridescent purple on their wing feathers.
Photograph by Bates Littlehales
The green head and yellow bill of the mallard duck is a familiar sight to many people living in the Northern hemisphere. In fact, the mallard is thought to be the most abundant and wide-ranging duck on Earth.
Mallards prefer calm, shallow sanctuaries, but can be found in almost any body of freshwater across Asia, Europe, and North America. They’re also found in saltwater and brackish water and are commonly found in wetlands.
The male, or drake, is the more distinctively colored of the mallards. Its iconic green head sits atop a white neckband that sets off a chestnut-colored chest and gray body. Females are mottled drab brown in color, but sport iridescent purple-blue wing feathers that are visible as a patch on their sides. They grow to about 26 inches (65 centimeters) in length and can weigh up to 3 pounds (1.4 kilograms).
Mallard groups can often be seen head dipping or completely upending in the water. They rarely dive though, spending their time near the surface and dabbling for invertebrates, fish, amphibians, and a variety of plants. They also graze on land, feeding on grains and plants.
Mated pairs migrate to and breed in the northern parts of their range and build nests on the ground or in a protected cavity. They normally lay about a dozen eggs, and the incubation period lasts just under a month. Mallards are territorial during much of this period, but once incubation is well underway, males abandon the nest and join a flock of other males.


Monday, April 1, 2013

Canada Goose


Canada Goose

 
Branta canadensis


Photo: A Canada goose watches over ten fuzzy babies as they swim
Once threatened with dwindling populations, conservation efforts have made the Canada goose very common throughout North America.
Photograph by Stephen St. John
The ubiquitous Canada goose is one of the best known birds in North America. It is found in every contiguous U.S. state and Canadian province at one time of the year or another.
Canada geese are adaptable to many habitats and may thrive wherever grasses, grains, or berries are available. Because of changing weather, settlement, and farming patterns, many Canada (not "Canadian") geese have begun to alter their migrations. Typically, the birds summered in northern North America and flew south when cold weather arrived. This cycle endures, but some northern populations have shortened their flight to traditional wintering grounds in the southern U.S. and Mexico. Other Canada geese have become permanent residents of parks, golf courses, suburban subdevelopments, and other human habitats across much of North America. In some areas, such as airports, they are so numerous that they are considered a nuisance. Just 50 geese can produce two and a half tons of excrement in a year.
When the birds do migrate, they form impressive and aerodynamic "V-formations." They can cover 1,500 miles (2,400 kilometers) in just 24 hours with a favorable wind, but typically travel at a much more leisurely rate. These noisy groups honk their way along established paths that include designated "rest stops." These social birds remain in flocks year-round, except while nesting.
Link: http://animals.nationalgeographic.com/animals/birds/canada-goose/


Wednesday, March 27, 2013

Snowy Owl


Snowy Owl

 
Nyctea scandiaca


Photo: A snowy owl perched atop a rock
The snowy owl's beautiful white plumage helps to hide it in its Arctic habitat. Only the males are completely white. Chicks are dark and spotted, while the females are white with spots on their wings.
Photograph by Norbert Rosing
The ghostlike snowy owl has unmistakable white plumage that echoes its Arctic origins.
These large owls breed on the Arctic tundra, where females lay a clutch of 3 to 11 eggs. Clutch size depends upon the availability of food, and in particularly lean times a usually monogamous pair of owls may not breed at all. Parents are territorial and will defend their nests against all comers—even wolves.
Young owls, especially males, get whiter as they get older. Females are darker than males, with dusky spotting, and never become totally white. Some elderly males do become completely white, though many retain small flecks of dusky plumage.
The snowy owl is a patient hunter that perches and waits to identify its prey before soaring off in pursuit. Snowy owls have keen eyesight and great hearing, which can help them find prey that is invisible under thick vegetation or snowcover. The owls deftly snatch their quarry with their sharp talons.
A snowy owl's preferred meal is lemmings—many lemmings. An adult may eat more than 1,600 lemmings a year, or three to five every day. The birds supplement their diet with rabbits, rodents, birds, and fish.
Read full here... http://animals.nationalgeographic.com/animals/birds/snowy-owl/


Wednesday, March 13, 2013

Macaw


Macaw

 
Psittacidae


Photo: Hyacinth macaw in flight
Of the 17 species of macaws, several are endangered, including the beautiful hyacinth, seen here in flight.
Photograph by Joel Sartore
Macaws are beautiful, brilliantly colored members of the parrot family.
Many macaws have vibrant plumage. The coloring is suited to life in Central and South American rain forests, with their green canopies and colorful fruits and flowers. The birds boast large, powerful beaks that easily crack nuts and seeds, while their dry, scaly tongues have a bone inside them that makes them an effective tool for tapping into fruits.
Macaws also have gripping toes that they use to latch onto branches and to grab, hold, and examine items. The birds sport graceful tails that are typically very long.
Macaws are intelligent, social birds that often gather in flocks of 10 to 30 individuals. Their loud calls, squawks, and screams echo through the forest canopy. Macaws vocalize to communicate within the flock, mark territory, and identify one another. Some species can even mimic human speech.
Flocks sleep in the trees at night, and in the morning they may fly long distances to feed on fruit, nuts, insects, and snails. Some species also eat damp soil, which may help to neutralize chemicals in their fruity diet and ease their stomachs.
Macaws typically mate for life. They not only breed with, but also share food with their mates and enjoy mutual grooming. In breeding season, mothers incubate eggs while fathers hunt and bring food back to the nest.
There are 17 species of macaws, and several are endangered. These playful birds are popular pets, and many are illegally trapped for that trade. The rain forest homes of many species are also disappearing at an alarming rate.
Read full here... http://animals.nationalgeographic.com/animals/birds/macaw/


Tuesday, February 26, 2013

California Condor


California Condor

 
Gymnogyps californianus


Photo: California condor in tree
Sacred to Native Americans and the largest birds in North America, the California condor teeters on the brink of extinction, saved only by captive breeding programs.
Photograph courtesy Scott Frier/U.S. Fish and Wildlife Service
The California condor is the largest flying bird in North America. Their wings may stretch nearly 10 feet (3 meters) from tip to tip. When in flight, these huge birds glide on air currents to soar as high as a dizzying 15,000 feet (4,600 meters).
Like other vultures, condors are scavengers that feast on the carcasses of large mammals, such as cattle and deer. When a big meal is available, the birds may gorge themselves so much that they must rest for several hours before flying again.
Condors were sacred birds to the Native Americans who lived in the open spaces of western America. Today, they are best known as the subjects of a famous captive breeding program that may save them from extinction.
After decades of decline, condors neared the point of extinction in the late 1970s, when only two or three dozen birds survived. No one is sure exactly what cause or causes contributed most to this decline. Many birds died from poison ingestion and illegal egg collection, and all felt the steady loss of the open lands over which they once soared. Fossil records also show that the birds occupied only a fraction of their former range when Europeans first reached America—perhaps because of the loss of the great prehistoric herds that formerly roamed the continent.
California condors mature and reproduce slowly. They don't breed until they are between six and eight years old, and the female lays only one egg every two years. If that egg is removed, however, she will lay a second or a third. With this in mind, scientists began to collect eggs for captive incubation. They also captured wild birds for captive breeding and, when the wild population dropped below 10 individuals, all of the remaining wild condors were brought into captivity in 1987.
Read full here... http://animals.nationalgeographic.com/animals/birds/california-condor/


Sunday, February 24, 2013

Snow Goose


Snow Goose

 
Anser caerulescens


Photo: Snow geese in water
Its numbers in dangerous decline in the early 20th century, the snow goose has made a stellar recovery, so much so that it has overrun its habitat.
Photograph courtesy Dave Menke/U.S. Fish and Wildlife Service
Snow geese are known for their white plumage, but many of them are actually darker, gray-brown birds known as blue geese. These birds were once though to be two separate species, but they have recently been found to be merely two different color morphs of the same bird. A single gene controls the color difference.
Snow geese are harbingers of the changing seasons. They fly south for the winter in huge, honking flocks that may appear as a "U" formation or simply as a large "snowstorm" of white birds. They spend the colder seasons in southern coastal marshes, bays, wet grasslands, and fields. Their diet is entirely vegetarian, consisting of grasses and grains, grazed from damp soils or even shallow water.
At winter's end, snow geese fly north to their breeding grounds on the Arctic tundra. Pairs mate for life, and produce two to six eggs each year in a shallow ground nest. Chicks can swim and eat on their own within 24 hours, but families remain together through the young's first winter. Families can be identified as groups during both the southern and northern migrations.
Read full here... http://animals.nationalgeographic.com/animals/birds/snow-goose/


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