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 Rhinoceros Iguana

 North America, Reptiles, Tropical Forests  Comments Off on The Rhinoceros Iguana
Dec 302009
Photo provided courtesy of Silvain de Munck on Flickr Creative CommonsHomeCarribean
Habitatdry rocky ground with cacti
Nichelarge herbivore
Favorite Foodleaves and berries
Body Lengthbetween 3 and 4 feet
Weight10 to 20 pounds
StatusVulnerable to Extinction
ThreatsHabitat loss, competition from invasive species

The rhinoceros iguana is a massive lizard, weighing as much as a beagle and rivaling the length a German shepherd from nose to tail tip. It gets its name from its mottled gray skin and protruding scales on its nose that resembles a rhino’s horn. Although they look ferocious, these iguanas are vegetarian.  They subsist exclusively on tender leaves and fruit from low-hanging shrubs in the rocky interior of the island of Hispaniola and immediate Caribbean. More often than not, these shy iguanas will bolt away from danger at high speed and seek refuge in hiding. However, it’s unwise to corner a startled rhinoceros iguana, for it can deliver a powerful bite and will strike out repeatedly with its muscular tail.

Females lack the large nose “horns” and domed helmet of the males, who are fiercely territorial during the mating season and will attack intruders to drive them from their territory and assert dominance. After mating, the female will lay between 10 and two dozen eggs that she will guard with her life in a small burrow. After three months, the eggs will hatch and the youngsters will be left by the mother to fend for themselves in a dangerous world. Few will be lucky enough to reach adulthood.

photo provided courtesy of Anubis333 on Flickr Creative CommonsDespite their formidable size and strength, rhinoceros iguanas are now vulnerable to extinction. Like many animal species native to islands, these iguanas are threatened by invasive species brought by colonial ships centuries ago. Predation and competition for food from pigs, dogs, rats, and cats have cut the numbers of wild rhinoceros iguanas significantly. Habitat destruction in the fragile economies of Haiti and the Dominican Republic has also driven this monster lizard from much of its former range. Its future is in doubt.