Friday, April 30, 2010
Thursday, April 29, 2010
Wednesday, April 28, 2010
- The Red-shouldered Hawk is divided into five subspecies. The four eastern forms contact each other, but the West Coast form is separated from the eastern forms by 1600 km (1000 mi). The northern form is the largest. The form in very southern Florida is the palest, having a gray head and very faint barring on the chest.
- Although the American Crow often mobs the Red-shouldered Hawk, sometimes the relationship is not so one-sided. They may chase each other and try to steal food from each other. They may also both attack a Great Horned Owl and join forces to chase the owl out of the hawk's territory.
- By the time they are five days old, nestling Red-shouldered Hawks can shoot their feces over the edge of their nest. Bird poop on the ground is a sign of an active nest.
- The Great Horned Owl often takes nestling Red-shouldered Hawks, but the hawk occasionally turns the tables. While a Red-shouldered Hawk was observed chasing a Great Horned Owl, its mate took a young owl out of its nest and ate it.
Monday, April 26, 2010
Saturday, April 24, 2010
Thursday, April 22, 2010
River otters are amphibious creatures known for their intelligence and playful nature. They can be found swimming in rivers, lakes and even in ocean bays. Their streamlined, sinuous bodies and long flattened tail helps propel the otter gracefully through the clear waters of North America. Otters are also excellent hunters, using sensory hairs on the snout called vibrissae to sense water turbulence that help them locate their meal of fish, mollusks and other small invertebrate.
Though solitary and wary of strangers, river otters can be sociable and easily domesticated creatures. They also are incredibly playful. Otters like to wrestle, chase one another around and slide down slick or snow-covered riverbanks. No hibernation for these little guys; otters are active year round. A layer of fat right underneath the skin and thick fur helps protect them even in the coldest of waters and winters.
River otter's fur consists of two layers; a coarse, waterproof outer coat and a softer, finer layer that keeps the animal warm. When in the water air bubbles cling to the outer hairs, covering the otter in what appears to be a silvery sheen. Unfortunately for otters, people enjoy their luxurious coats as well and are hunted their pelts. The popularity of otter fur outerwear has contributed to the dramatic decrease of river otters for the past 200 years. However, hunting isn't the only cause for the river otter's demise.
Although once abundant in North America, river otters have suffered greatly from habitat loss, water pollution, the fur trade and other threats. Historically, river otters were found in great numbers in the waterways and coastal areas throughout Canada and the United States. Today, river otters have been virtually eliminated in many parts of their original range. Heavily populated areas in the Midwest, East Coast and the Southeast have been greatly affected. Thanks to successful reintroduction efforts, otter populations are slowly being restored in many of these states, and lucky for us, Indiana is one of them.
Wednesday, April 21, 2010
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.
The bald eagle, with its snowy-feathered (not bald) head and white tail, is the proud national bird symbol of the United States—yet the bird was nearly wiped out there. For many decades, bald eagles were hunted for sport and for the "protection" of fishing grounds. Pesticides like DDT also wreaked havoc on eagles and other birds. These chemicals collect in fish, which make up most of the eagle's diet. They weaken the bird's eggshells and severely limited their ability to reproduce. Since DDT use was heavily restricted in 1972, eagle numbers have rebounded significantly and have been aided by reintroduction programs. The result is a wildlife success story—the U.S. Fish and Wildlife Service has upgraded the birds from endangered to threatened.
Though their numbers have grown in much of their range, bald eagles remain most abundant in Alaska and Canada. These powerful birds of prey use their talons to fish, but they get many of their meals by scavenging carrion or stealing the kills of other animals. (Such thievery famously prompted Ben Franklin to argue against the bird's nomination as the United State's national symbol.) They live near water and favor coasts and lakes where fish are plentiful, though they will also snare and eat small mammals.
Bald eagles are believed to mate for life. A pair constructs an enormous stick nest—one of the bird-world's biggest—high above the ground and tends to a pair of eggs each year. Immature eagles are dark, and until they are about five years old, they lack the distinctive white markings that make their parents so easy to identify. Young eagles roam great distances. Florida birds have been spotted in Michigan, and California eagles have traveled all the way to Alaska.