Jan 152010
 
photo provided courtesy of mybulldog on Flickr Creative CommonsHomeNorth and South America
Habitatvaried: tropical and temperate forest, grassland, desert, and mountains
Nichenocturnal hunter
Favorite Foodsmall mammals
Lengthup to 2 feet
Weightup to 5 pounds
StatusCommon
ThreatsHabitat destruction





















The Great Horned Owl is the largest owl in North America, and its range extends from Northern Canada down to Tierra del Fuego. It gets its name from the tufts of feathers on either side of its head that resemble horns from a distance. A silent killer of the night, it is one of the world’s most successful birds.

Great Horned Owls are some of the most sedentary birds in the world, rarely venturing far from their home tree. Because of their adaptations, they don’t need to fly far in search of food. Small mammals are plentiful across the Great Horned Owl’s wide range across North and South America, and this amazing bird has an extensive hunting arsenal. Its binocular vision is so acute that it can spy a mouse over 100 feet away, and its hearing can detect tiny movement in the leaf litter below its tree. Although owls can’t move their eyes in their sockets, they can turn their heads almost completely around their axis, allowing them to zero-in on prey. Finally, the soft feathers of an owl muffles the sound of flight, making its deadly approach nearly silent up until the point it sinks its razor-sharp talons into an unfortunate animal.

Great Horned Owls make their nests in trees, usually in a hollowed-out trunk or the abandoned nest of a hawk or crow. In sparser areas, they will nest in rocky alcoves. Although the female is the one to incubate the eggs, both parents will tend to the fledgling chicks for about 6 weeks until they leave the nest. Great Horned Owls are very territorial birds, even when not rearing young, but will defend their nests with resolve. They have been known to dive-bomb humans to frighten them away from their trees if they get too close.





Habitat destruction is the greatest threat facing Great Horned Owls because of their dependence on trees for nesting. However, their wide range has afforded them a buffer against encroachment, and they are still common in many regions of North and South America.

The Andean Condor

 Birds, Mountains, South America  Comments Off on The Andean Condor
Jan 092010
 
photo provided courtesy of orchidgalore on Flickr Creative CommonsHomeWestern South America
Habitatmountains and coastlines
Nichelarge aerial scavenger
Favorite Foodcarrion
Wingspanup to 11 feet
Weightup to 25 pounds
StatusNear Threatened
Threatshunting, poisoning, habitat loss















The largest flying bird in the world carves its home among the jagged peaks of South America’s Andes Mountains. Soaring as high as 18,000 feet on rising air currents, the Andean Condor is one of the most impressive birds on Planet Earth.

It is a giant bird, with a body measuring nearly 4 feet in length and weighing up to 25 pounds. In order to keep that kind of weight aloft in the air, the Andean Condor uses its massive wings that can stretch 11 feet from tip to tip. Although that wing length is rivaled by other birds like large storks and albatrosses, no other bird comes close to the wing area of an adult Andean Condor. It relies on these giant wings to stay aloft, preferring to gain altitude and glide on rising thermals rather than expending energy on more propulsive flight. Using only a few wing flaps, this condor can travel huge distances in its search for food thousands of feet below.

Like all other vultures, the Andean Condor is primarily a scavenger, feeding on animal carcasses that dot the mountains and coastline of western South America. It uses its keen eyesight to locate everything from dead alpacas to beached whales from dizzying heights aloft. In addition to carrion, Andean Condors also will frequent the nesting grounds of seabirds on the Peruvian Coast. They snatch eggs from the nests of other birds that are no match for their intimidating size.

Andean Condors have fared better than their critically endangered cousins to the north, the California Condors. However, they are subject to similar threats due to their breeding habits. They produce only a single egg every two years, which means that a significant reduction in population could spell disaster for the species as a whole. Luckily, the remoteness of their habitat in the unforgiving heights of the Andes and their plentiful supply of dead meat has protected them so far.

The Marine Toad

 Amphibians, Australia, Invasive Species, South America  Comments Off on The Marine Toad
Jan 012010
 
photo by Sam Fraser-Smith on Flickr Creative CommonsHomeCentral and South America, and introduced worldwide
Habitatnearly every temperate habitat, from rainforest to savannah, farmland to suburbia
Nichelarge opportunistic predator
Favorite Foodinsects
Lengthup to 9 inches
Statuscommon
Invasive Species

























The marine toad is the largest toad on Earth by far, growing as big as 9 inches in length. They are insatiable hunters, prowling their territories by night and gobbling up anything that can fit in their mouths. In addition to their staple diet of insects, they will scarf down unlucky salamanders and even small frogs. As if their massive size wasn’t enough to deter predators, marine toads also sport a deadly defense mechanism. If an animal picks up the toad in its jaws, special glands in the amphibian’s skin will ooze a highly toxic venom. The hapless predator scarcely has time to wish it never chose the toad as its last meal, as most are killed within 15 minutes of ingesting the poison.

In many regions of the world, especially Australia, the marine toad is an invasive species, competing with native frogs and toads for food and water. In certain cases, the introduction of marine toads was deliberate, particularly in countries that grow sugar cane. Since these toads are so voracious and are useful in pest control, they were thought to be effective watchdogs of sugar cane crops and earned the name cane toad. Although some farmers may have benefited from the introduction of cane toads, local ecosystems have been devastated. Marine toads are tough amphibians that can thrive in just about any environment on earth. Unlike frogs, they have thick, warty skin that allows them freedom from standing water except for mating. They are also tolerant to salt water, which amphibians usually shun, and can go without water entirely for long stretches of time. They are the ultimate survivors of the amphibian family, for better or for worse.

Because of their wide distribution, high tolerance, and high reproductive rate (over 20,000 eggs are laid in a clutch), marine toads are common and unlikely to be impacted by many of the same forces jeopardizing the survival of their frog and toad cousins. The marine toad is an example of how a hardy survivor can carve out its own niches in new areas, to the detriment of other species.

The Giant Anteater

 Grasslands, Mammals, South America, Tropical Forests  Comments Off on The Giant Anteater
Jan 012010
 
photo provided courtesy of Just Chaos on Flickr Creative CommonsHomeCentral and South America
Habitatforests and grasslands
Nichelarge insectivore
Favorite Foodants and termites
Lengthbetween 5 and 10 feet nose to tail tip
Weightup to 85 pounds
StatusVulnerable to Extinction
Threatshabitat loss and hunting



















The giant anteater is one of Earth’s weirdest looking mammals. Sporting a long, tubular snout and a tail that looks whisked from an ostrich, this resident of South America shuffles throughout the rainforests and plains searching for what concerns him. And what concerns the giant anteater is ants.

The giant anteater’s amazing 2-foot-long tongue is covered with tiny, backward-facing spines that are slathered in sticky saliva when the animal feeds. After it’s broken into the nest with its muscular forearms and wicked claws, the anteater will then start snaking its tongue in and out, lapping up any ant it touches.

Miraculously, the giant anteater obtains most of its water from the ants it consumes. Since it depends on ants for not just its food but also its water, it has has devised a way to ensure it always something to eat in its territory. It only feeds for about a minute at each of the nests it visits. Although it can flick its tongue in and out 150 times in that minute, the anteater only consumes about 1% of the ants it needs daily from a single nest. However, because it exercises restraint, the surviving ants have a chance to rebuild the nest and rear more ants. Thus, because the giant anteater is careful not to over-exploit precious resources, its ensured food for life.

Not only does it have a pretty sweet life on the eating end, but the giant anteater has few enemies to fear other than man. Although big cats like puma and jaguar will attack this german-shepard-sized tank of an animal, they will meet with stiff resistance. It looks like Snuffy from Sesame Street, but the giant anteater can easily overpower even the stoutest foe. Punching out with its long front claws, it can deliver devastating wounds to attackers. And if its able to hug the predator with a firm grip, then you can imagine what happens to flesh and bones under claws and muscle designed to rip open trees. But these normally gentle giants prefer to avoid confrontation. Their extremely keen senses of smell and hearing help them to detect both food and danger as they walk awkwardly on their knuckles to prevent damage to their essential front claws.

photo provided courtesy of Just Chaos on Flickr Creative CommonsGiant anteaters are one of the most successful mammals on the South American continent, but they will only continue to thrive if man allows it. They are hunted for their furs and have been driven from much of their former range due to habitat destruction in the process of industrial development. They are now vulnerable to extinction.

The Atacama Desert of South America

 Deserts, South America  Comments Off on The Atacama Desert of South America
Nov 072009
 
photo provided courtesy of Phillie Casablanca on Flickr Creative CommonsLocationPeru and Chile
Annual Rainfallat most,  1mm per year
Ageover 20 million years









Deserts are by definition the driest places on earth. Since water is so essential to life on Earth, deserts are tough places for organisms to carve out a niche, and the driest desert on earth is without parallel on the scale of harsh environments. The Atacama desert of South America receives such a negligible amount of rain that it’s difficult to even detect when it does fall. Indeed, the recorded average rainfall in this bone-dry desert was a mere 0.02 inches over 30 years. That’s as dry as it gets on planet Earth.

The Atacama Desert, like the Namib Desert and Australian Desert, lies adjacent to a coastline, stretching from Peru in the North to central Chile in the south. This narrow desert is bordered on the other side by the massive Andes Mountains, a spine of peaks that divides the entire continent of South America. Both of these factors, ocean and mountain, create the conditions that make the Atacama Desert so arid.

Ocean currents form half of the equation. The current that runs along the western coast of South America, the Humboldt Current, carries cold water from Antarctica northward. This water chills the surface of the Pacific, limiting the amount of water that evaporates into rain-forming clouds. Instead, a dense fog called the camanchaca, and thin, whispy stratus clouds are produced. Neither of these produce rain for Western South America south of Peru.

The second factor that limits rainfall in the Atacama Desert is the Andes Mountain chain. Like the Himalayas limiting rainfall in the Gobi Desert of Asia, the Andes form a barrier to any moisture coming from the Amazon River basin. Clouds are pushed up the slopes of these great mountains and deposit their rain on the side facing the East. Wedged between these two limiting factors  – cold ocean currents and high mountains – the Atacama is lucky to receive any rainfall at all. To make matters worse, the majority of the desert lies in an inland depression, that blocks access to the moist fogs coming off the Pacific. These conditions have remained relatively unchanged for millions of years, and in addition to being the driest desert on earth, the Atacama desert is also one of the oldest.

photo provided courtesy of 22BB on Flickr Creative CommonsWhat life does exist does so primarily around what are called “lomas,” areas of higher elevation that receive some of the moisture from the camanchacas fog coming off the ocean. Very few plants can survive in the gaps between the lomas, and as a result, food chains do not form. Some regions of the Atacama desert are completely devoid of life. Among the hardy plants that inhabit the region are more than 60 species of cactus, influding 25 species unique to the region. A number of bat and bird species also live along the lomas. Most mammal species are confined to the lomas and on the foothills of the Andes, including the guanaco, a small relative of llamas.

Human settlement in the Atacama Desert is limited to areas that can obtain water. To the north, small villages crowd around rivers and mining operations. Closer to the coast, residents stretch large nets to catch the fog as it comes off the Pacific Ocean. The moisture condenses on the nets and then drips into trays and pipes that collect the drinking water in large reservoirs. Because of the overuse and contamination of rivers, this condensor method of capturing water is the only means of life for many people living in the region.

The Atacama Desert is a land of extremes, all of which tell a fascinating story of the way earth’s geosystems interact to produce a final product.