Saturday 16 October 2010

Osprey

An osprey preparing to dive 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.
Most ospreys are migratory birds that breed in the north and migrate south for the winter. They lay eggs (typically three), which both parents help to incubate. Osprey eggs don't hatch all at once, but are staggered in time so that some siblings are older and more dominant. When food is scarce these stronger birds may take it all and leave their siblings to starve.

Tuesday 5 October 2010

king vultures seek carrion

Typically drifting on air currents that keep them aloft, king vultures seek carrion, filling an important ecological niche.
Like other vultures, the king vulture is a scavenger. These large birds glide on air currents, conserving energy while searching the forests or savanna below for the corpses of dead animals. Because of their unappetizing eating habits, they fill an ecological niche, and may help to prevent the spread of disease by disposing of rotting remains.
King vultures have a very colorful look that distinguishes them from their vulture relatives. They are predominately white, with black tails and wing tips. They have piercing, often straw-colored eyes and multicolored (yellow, orange, and red) heads and necks.
map-king-vulture- 
Though brightly colored, the vulture's head and neck are bald. This may help the fastidious birds to stay clean, and ensure that bacteria-laden animal remains don't fester in the bird's plumage where they could spread disease.
Sarcoramphus papa are among the bird world's largest scavengers and have powerful, hooked beaks that are excellently adapted for tearing open tough carcasses. They can often access meals that other vultures cannot, and smaller birds usually give way when they arrive to feed.
These birds nest on the ground, and females lay a single egg—which both parents incubate. Both parents may also care for infants, bringing back dinner in their stomachs and regurgitating it for their young to enjoy.
King vultures are found from Mexico south to Argentina. Some suggest that the bird's name stems from an old Mayan legend in which this vulture was a "king" or "lord" that carried messages between humans and the Gods.

Macaws....brilliantly colored

Of the 17 species of macaws, several are endangered, including the beautiful hyacinth, seen here in flight.
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.
map-macaw
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.
Hyacinth, red-fronted, and blue-throated macaws are seriously endangered. The glaucus macaw and Spix's macaw may already be extinct in the wild.

Monday 4 October 2010

Blue-Footed Booby

Not just attractive physical features, the blue feet of this booby can be used to cover its chicks and keep them warm.

Blue-footed boobies are aptly named, and males take great pride in their fabulous feet. During mating rituals, male birds show off their feet to prospective mates with a high-stepping strut. The bluer the feet, the more attractive the mate.
These boobies live off the western coasts of Central and South America. The Galápagos Islands population includes about half of all breeding pairs of blue-footed boobies.
Like other boobies, blue-foots nest on land at night. When day breaks, they take to the air in search of seafood, sometimes fishing in cooperative groups. They may fly far out to sea while keeping a keen eye out for schools of small fish, such as anchovies. When their prey is in sight, these seabirds utilize the physical adaptations that make them exceptional divers. They fold their long wings back around their streamlined bodies and plunge into the water from as high as 80 feet (24 meters). Blue-footed boobies can also dive from a sitting position on the water's surface.
Blue-footed boobies also use their webbed feet to cover their young and keep them warm. When a typical brood of one to three chicks hatches, both parents feed and care for them.
All half-dozen or so booby species are thought to take their name from the Spanish word "bobo." The term means "stupid," which is how early European colonists may have characterized these clumsy and unwary birds when they saw them on land—their least graceful environment.

Eastern bluebirds

Eastern bluebirds are known for their vibrant coloring and sweet songs.
There are three species of these colorful North American birds. Eastern and western bluebirds have a reddish brown breast, which contrasts with their predominately blue plumage. Their relative, the (male) mountain bluebird is entirely blue.
Eastern bluebirds are primarily found east of the Rockies, and range from Canada to Mexico and Honduras. They are much admired for their lovely coloring and for a distinctive song that many hear as "chur-lee, chur-lee." The eastern bluebird is the state bird of both New York and Missouri.
Western bluebirds are found west of the Rocky Mountains from Canada to Mexico. The mountain bluebird also inhabits much of western North America—often at elevations above 7,000 feet (2,133 meters).
Bluebirds eat small fruits and hunt insects, spiders, and other creatures from above. The birds perch, watch, and then swoop to the ground to pounce on their prey.
Pairs mate in spring and summer, when they construct small, bowl-shaped nests. Females lay four or five eggs and incubate them for about two weeks. Young remain in the nest, cared for by both parents, for an additional 15 to 20 days. Bluebirds often have two broods in a season. Sometimes, a young bluebird from the first brood will remain in the nest and assist its parents in caring for the second.
Bluebirds living in higher latitudes may head south if food becomes scarce or temperatures too cold. Mountain bluebirds typically migrate to lower elevations during the same lean seasons.
Bluebirds are considered fairly common, but their numbers have declined substantially during the last century. Populations have been given a boost by the birdhouse boxes that have become popular in many parks and backyards.

Prairie dogs emerge

These charismatic, rabbit-size rodents live on North America's prairies and open grasslands in only a fraction of their former numbers.
Prairie dogs live in underground burrows, extensive warrens of tunnels and chambers marked by many mounds of packed earth at their surface entrances. Burrows have defined nurseries, sleeping quarters, and even toilets. They also feature listening posts near exits, so animals can safely keep tabs on the movements of predators outside. Prairie dogs spend a lot of time building and rebuilding these dwellings. Other animals benefit from their labors. Burrows may be shared by snakes, burrowing owls, and even rare black-footed ferrets, which hunt prairie dogs in their own dwellings.
Family groups (a male, a few females, and their young) inhabit burrows and cooperate to share food, chase off other prairie dogs, and groom one another. These group members even greet one another with a prairie dog kiss or nuzzle. Young pups are very playful and can often been seen romping near their burrows.

Black-tailed prairie dogs, the best known of the five prairie dog species, live in larger communities called towns, which may contain many hundreds of animals. Typically they cover less than half a square mile (1.3 square kilometers), but some have been enormous. The largest recorded prairie dog town covered some 25,000 square miles (65,000 square kilometers). That Texas town was home to perhaps four hundred million prairie dogs.
Another prairie dog species, the white-tailed prairie dog, lives in the western mountains. These rodents do not gather in large towns but maintain more scattered burrows. All species hunker down in winter and burn the reserves of fat they have stored during more plentiful seasons. White-tails may hibernate for up to six months on their mountain plains, while their black-tailed cousins sometimes emerge to feed on especially warm days.
These large squirrels emerge from their burrows in daylight to forage and feed on grasses, roots, and seeds. They communicate with loud cries. A warning cry, for example, will send a town's denizens hustling to their holes at the approach of a badger, coyote, or other predator. A second, "all-clear" call alerts the community when the danger has passed.
Much of the Great Plains has been converted to farming or pastureland, and prairie dogs are not often welcome in such places. Because of their destructive landscaping, they are often killed as pests. During the 20th century, about 98 percent of all prairie dogs were exterminated, and their range has shrunk to perhaps five percent of its historic spread.