The Egyptian Vulture

 Africa, Asia, Birds, Deserts, Endangered Species, Grasslands, Mountains  Comments Off on The Egyptian Vulture
May 062010
HomeAfrica, Asia, Southern Europe
HabitatHot, dry regions
Favorite FoodCarrion, eggs, cow manure, rotted plants
LengthUp to 28 inches
WeightUp to 4 pounds
Threatspoaching, poisoning

With its wrinkled yellow face and feathery locks like white hair, the Egyptian vulture has a strangely human look of cunning. Once a common sight across the dry expanses of Africa and Asia, these small scavengers are now endangered, driven to the fringes of their former range by forces out of their control.

Egyptian vultures are small for carrion birds, not much bigger than crows. And like crows, they have a broader capacity for problem solving than most birds. There’s no better example of their ingenuity than their behavior around ostrich eggs on the African savannah. An unguarded ostrich nest is a boon for any animal, especially a scavenger in regions with fierce competition for food. However, such a small bird can’t get into such an imposing egg without help. So over thousands of years, these crafty vultures have developed proficiency in a very powerful adaptation. Tools.

That’s right. Tools aren’t just for humans and those in the animal world most like us. Egyptian vultures are one of the few birds that can truly make use of tools in the wild. Once a bird has located an egg, it will search the surrounding ground for a suitable stone, pick it up in its beak, and hurl it down on the egg repeatedly. All it needs is a crack in order to pry the egg open with its beak before 300 pounds of angry ostrich mother discovers what it’s up to.

Egyptian vultures need to be wily because they so often get muscled out of the pecking order at carcasses by other vultures. Even if they do reach a dead animal first, they’re not powerful enough to tear meat from a fresh kill. They must wait for stronger scavengers like hyenas and white-backed vultures to shred the flesh for them.

Nowadays, the Egyptian vulture is a rare sight in much of Africa and Asia where up until very recently it boasted impressive numbers. Ironically, these birds that help stall the spread of disease to humans have been pushed to the brink under the mistaken belief that they spread it. Also, improved veterinary medicine has done wonders for livestock, but has wreaked havoc on these birds once certain chemicals enter the food chain and poison them. Strange how the first bird ever protected by law (in Ancient Egypt) is now facing such grim prospects in a more enlightened age.

*filmstrip photo provided courtesy of belgianchocolate on Flickr Creative Commons

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
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.

Horned Lizards

 Central America, Deserts, North America, Reptiles  Comments Off on Horned Lizards
Jan 102010
photo provided courtesy of soulsurvivor08 on Flickr Creative CommonsHomeSouthern North America, Central America
Favorite Foodants
Length6 inches or less
StatusSome Species Threatened
Threatshabitat destruction, pesticides, invasive ant species

Of all the animals that can scrape out a living in the world’s deserts, lizards are among the most adapted to such harsh environments. Their hard scales provide a barrier against water loss and the abrasiveness of wind and sand. They obtain most of their water from their diverse diets and can survive long stretches of time without food. Horned lizards are among the most successful group of desert reptiles and comprise 14 different species of lizards that live in the arid regions of North and Central America.

As their name implies, horned lizards have a number of spiked projections on their head, body, and tail. In addition to their flattened, toad-like bodies, horned lizards are often referred to as horned toads or horny toads. The horns are used in courtship displays and also act as a defense against predators. However, it’s their rough, mottled skin blending seamlessly with their rocky surroundings that affords them the best protection. As long as the lizard remains still, it is virtually invisible to most predators. Some horned lizards possess more specialized defenses, like shooting blood from the eyes to confuse and frighten predators.

One of the most pressing issues of life in the desert is regulating body temperature. Like all reptiles, horned lizards are at the mercy of their surroundings when it comes to their internal heat. In order to maintain optimal temperature in the desert land of extremes, horned lizards will burrow into the sand or soil to avoid the murderous midday sun and cold temperatures at night. As the morning sun creeps over the horizon, they will raise their heads out of their burrow in order to first warm their brains. As soon as all systems are operational in the nervous system, horned lizards will then remove the rest of their bodies from the sand and begin their daily routines of basking in the sun and searching for ants to gobble up.

photo provided courtesy of Ben Goodwyn on Flickr Creative CommonsHorned lizards are still common across the deserts of the Southwestern United States and Mexico. Since they live in an environment that is inhospitable to man, they have been spared much of the trouble that has befallen many of their lizard relatives in other regions of the world. However, human development in arid regions still poses a looming threat.

The Honey Badger

 Africa, Deserts, Grasslands, Mammals, Tropical Forests  Comments Off on The Honey Badger
Nov 302009
photo provided courtesy of kaz2803 on Flickr Creative CommonsHomeSub Saharan Africa, West and South Asia
Habitatvaried, including grasslands, deserts, and tropical forests
Nicheopportunistic predator
Favorite Foodhoneybee larvae
Lengthup to 3.5 feet nose to tail tip
Weightup to 30 pounds
StatusLower Risk

When people think of ferocious animals, they think of the big ones – sharks, lions, tigers, bears. But as it turns out, there are few animals on earth that are stouter of heart than a certain mammal no bigger than a terrier. Cross a honey badger and you cross what Guinness named the most fearless mammal on earth.

The honey badger is native to sub-Saharran Africa and South Asia, living in a variety of habitats in its wide range. From dry savanna to dense forest, it trots over great distances in constant search of food to fuel its impressive metabolism. Seeking safe haven in underground burrows or inside rock crevices, the honey badger is an active hunter in the daylight hours. Most badgers are nocturnal and have poor eyesight, relying instead on a highly developed sense of smell to find food. But the honey badger is built for hunting anything it can get its mouth around during the light of day. Everything from worms and termites up to formidable animals like porcupines and snakes are potential sources of food for this miraculous member of the weasel family.

Being active in the daytime is not the only trait that sets the honey badger apart from other badgers. Indeed, it is only distantly related to what are called “true badgers” – a family that includes the familiar American and Eurasian badgers. The honey badger possesses the long digging claws of its cousins, but its teeth are not as adapted for crushing. It has fewer teeth, but those it has are adapted to biting and holding on tight. It also sports a defense that’s more commonly developed in skunks than badgers. If an enemy gets too close, the honey badger will unleash a chemical assault from its backside. Specialized anal glands secret a nauseating liquid that can drive off even the most fearsome foe.

As the name implies, the honey badger is fond of the sweet stuff of honeybees. And remarkably, through the wonders of evolution, it has devised a rather ingenious way of obtaining it. A certain type of bird in Africa, the black-throated honeyguide is its partner in crime. The honeyguide is able to locate bees’ nests by virtue of its flight, but it has no means of plundering the nest by itself. The bird is too small to brave a swarm of bees and tear open a nest to obtain the honey it wants. Instead, it relies on some hired muscle. After it has located a nest, the next step is for the bird to find a nearby honey badger. Communicating through its flight and calls, the bird will then lead the badger to the nest. Undeterred by the stings on its thick hide, the honey badger will rip the nest to pieces with its strong claws, allowing both badger and bird to feast on the sweet reward of honey and bee larvae.

Aside from its interesting relationship with birds, the honey badger is known for its fearless disposition. Its skin is thick and tough, and hangs loosely from its body, reducing damage to vital organs if it is bitten in a fight. But defense is only part of its reputation. The honey badger can dish out punishment with the best of them. If its noxious chemical musk isn’t enough to drive away an assailant, it can bite with great force and will not let go until its adversary loses consciousness or shakes the badger off. The honey badger proves that bravery in the animal kingdom can come in small packages.

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.