Bird brain

Because of something called imprinting, some birds may be confused about exactly who their mother is. Imprinting, a term first used by Austrian zoologist Loren Eisley, refers to a period of time in a bird’s life when it bonds with its mother. Usually this occurs shortly after a bird hatches. Once the bond is established, it is very hard to wipe out—and it affects the way that baby bird learn social and survival skills.

Imprinting is strongest in animals that leave the nest immediately after hatching, such as ducks or chickens. For this reason, it seems that nature has developed this way to keep the young, defenceless birds from wandering too far from their mother’s protection.

After a baby duck or chick hatches and opens its eyes, it considers the first moving object it spots to be its mother. It will follow that creature or thing around, imitating it and learning its behaviour, such as how to find food and greet other animals.

In wood ducks, the bond from imprinting is especially strong. Because of imprinting, the babies recognize their mother’s call. These birds nest high in trees. The mother waits for her ducklings to hatch and then flies to the ground where she calls up to her babies. This I’ve seen myself in my many years learning gardening! One by one, they drop out of the nest, plummeting up to 50 feet (15m) to the ground where thy trust they will join their mother.

Scientific tests show that if their biological mother isn’t around during the imprinting period, some birds will bond with other things—a puppet held by a human, a dog, or even a little girl, as is the case for geese in the 1996 film Fly Away Home.

 

 

Changing minds

In the 20th century, conservation groups became established and concern grew among the public over the slaying of birds for scientific purposes, as well as for use in clothes and hats. Ornithologists decided to reconsider their methods. Over time, studying birds in their natural setting without killing the bird became favoured to the “shotgun school” method.

One ornithologist who believed in this idea was Ludlow Griscom. “I started learning local birds back in 1898,” he said. “In New York City, unlike Boston, an interest in birds was not respectable. It just wasn’t done. You could hunt and shoot birds, but you couldn’t just ogle them.”

Griscom relied on field observation, and his ability to correctly identify a bird at a distance was often questioned by traditional ornithologists. Once, out in the field with an ornithologist who still believed in killing birds to identify them, Griscom identified a female Cape May warbler. To be sure, the traditional ornithologist killed the bird, which turned out to be a female Cape May warbler. After several other correct identifications by Griscom, the traditionalist was convinced that killing birds wasn’t always necessary.

Griscom’s technique of field observation was simple: “I keep a daily record book which enters the field trip, the list of birds seen, careful counts or estimates of the number of individuals of every species and sufficient notes on the weather and migration…From this it is a simple matter to draw off the data from any particular area in which I am working at the moment.”

However, even Griscom felt that sometimes killing birds to study them was okay.

“Considerable experience in the field work has convinced me that…the securing of the specimen, either for exact identification of rare stragglers of for the enrichment of the local highly educational exhibition collections of the museums properly devoted to this purpose, does (sometimes serve) to advance the interests of science.”

MODERN THINKING

Both Audubon and Griscom’s influence over ornithology is best shown in Roger Tory Peterson’s work. Not only did Peterson work with Griscom, but Peterson, like Audubon, spent a lot of time drawing birds. Like Audubon and Griscom, Peterson’s love of bird watching was simply a hobby at first. “I was fascinated by birds and that set me distinctly apart,” he said, of growing up in the early 1900s.

“(Where I grew up), and throughout the nation, bird watchers were rare. They were considered kooks.”

However, it became a career for him when he compiled his information into a 1934 book, A Field Guide to the Birds. He was clear on what set him apart: “Other ornithologists…had worked out the field marks of most birds. I combined their knowledge with my visual presentation and…carried the idea through.”

Peterson’s book introduced the “Peterson Identification System.” Traditional field identification required a bird watcher to identify practically everything on the bird—from its markings and color to the size of its body, feet, wings, claws, and beak. Peterson’s system enabled bird watchers to identify birds by recognizing only a few unique physical traits. It uses field marks, which are like a bird’s fingerprints except that they are in the form of a certain color or shape of a bird’s face, wings, wing tips, tail, or body.

 

Bird Lovers!!!

The study of birds, called ornithology, has changed a lot over the years. Three leaders helped define the movement. While John Audubon expanded the idea of what should be studied about birds, Ludlow Griscom helped develop how they should be studied. Roger Tory Peterson developed his own system that helped simplify these ideas so that anyone—even you—could easily spot particular birds. What they all shared is a passion for birds.

HOW IT BEGAN

John Audubon, a famous wildlife artist in the early 1800s, had no formal training in the study of birds and was often criticized by his wife’s family for “forever wasting his time hunting, drawing, and stuffing birds. We fear he will never be fit for any practical purpose on the face of this earth. However, Audubon was able to turn his passion for birds into a career. His love of the then-emerging science called ornithology helped draw attention to the field.

Ornithology in the 1800s concentrated on the study of a bird’s ancestry and/or relationship to different groups of birds. However, Audubon introduced the idea of studying a bird’s behaviour. He was interested in studying a bird’s habits, mating rituals, migration, nests, and nest-building activities. Perhaps his greatest contribution to ornithology was the completion of the Ornithological Biography, a series of five books covering almost 500 birds. Published in the 1830s, it validated Audubon’s skill as a scientist, rather than simply a wildlife artist.

Much of Audubon’s study and drawings came from birds that he had shot to examine. In his early 20s in Louisville, Kentucky, Audubon and a friend cut a hole in a tree that was a known roost for swifts. After Audubon determined that there were thousands of swifts in the tree, the men proceeded to catch and kill 115 of them to study.

On another occasion in the field, Audubon was intrigued by a flock of herons and proceeded to kill and study them, only to find that the birds had already been researched by another ornithologist.

Audubon wasn’t doing anything out of the ordinary for that time period. During the early 19th century, hunting, collecting, as well as displaying animal trophies and stuffed, preserved animals was popular.

Birdie’s Wings

Feathers provide birds with warmth, protection in the rain, and coolness in heat. They are made of a tough, flexible material called keratin. Like hair, feathers are made of protein, and a bird can move its feathers using muscles. Each feather has a hollow, central shaft with vanes—the two halves of the feather—on each side. Vanes are made up of barbs—thousands of thin branches that angle toward the feather’s tip. On both sides of each barb there are even smaller branches called barbules.

Some birds don’t use their wings to fly. One group of flightless birds is called ratites. This family consists of the heaviest living bird, the ostrich, as well as rheas and kiwis. Their wings are relatively small in comparison to their bodies. Since they don’t fly, their feathers don’t have to be smooth; their outer feathers remain fluffy. In general, birds that don’t fly develop thicker bodies and strong legs and feet adapted for running. Another group of flightless birds are penguins. Penguins have wings that don’t fold. Their wing bones are flat, forming a broad paddle, which helps them swim.

Contour feathers cover the body, especially the wings. Their various parts are held together by barbules that can interlock like Velcro to create a smooth, solid surface that makes flying, gliding, and even swimming easier. Down feathers lie under contour feathers to help keep birds warm. Their fluffiness keeps in pockets of warm air for insulation.

For feathers to work properly, they must be smoothed out and arranged with their barbules hooked together. Almost all birds have an oil gland under their tail that they can reach back and squeeze with their beaks. Using their feet and beak, they rub this oil over their feathers to make them shiny and waterproof. Birds who fix their feathers this way are preening. During preening, a bird will nibble with its beak along the sides of one feather at a time. Of course, birds that lack this gland—such as frigate birds—get soaked when it rains.

Like beaks and feet, wings are adapted to the bird’s environment. There are four wing styles for flying birds. A half-moon-shaped wing is found on birds used to a rapid take-off, such as woodpeckers, and other birds that are used to small spaces and the need to flee quickly. These wings also have some spacing between the feathers, making them lighter and easier to move. The downside is that these wings aren’t made for fast or long-term flights.

Swifts, swallows, and other birds of prey have long, narrow, and pointed wings with no spaces between the main feathers. These “solid” wings are angled backward, similar to an airplane wing, allowing high-speed flight.

The other two types are similar in style, but different in function. The “gliding wing” is typical of sea birds, such as gulls. These wings are long, narrow, and flat, with no spaces between feathers. The “soaring wing” structure is typical of eagles, storks, and vultures. These are different from the gliding wings in that there are wide spaces between the feathers; they are shorter to deal with changes in the air currents; and they’re wider to enable the bird to carry prey.

Just as other animals shed their fur or skin, birds shed their feathers a few at a time and replace them in a process called molting. It usually takes place during a time that is best for the bird—usually after breeding and before migration. For this reason, many birds molt only once a year. If a new feather is damaged, it cannot be replaced until the next molting. Penguins lose all their feathers within two weeks, though new feathers are already growing by the time the old ones all fall out. Eagles, on the other hand, molt slowly. Because they need feathers for flying, clusters of feathers may stay with an eagle for two or three years.

Feather color is very important for attracting mates and displaying to other birds. Peacocks are an excellent example of a bird that uses color to its advantage. During mating season, when a male peacock sees a female—which looks like an ordinary brownish bird—he

Ill lift his green-and-blue tail straight up and fan it out, making a rattling sound. Of course, colors can also act as a disguise for birds in some settings. The Australian frogmouth hides by sitting on a branch and lifting its head up, so that its brown color blends in with the branches.

Feather colors are produced by two substances called pigments—melanin and carotenoids. Melanin, made in a bird’s body, is responsible for blacks, browns, and some yellows, while carotenoids produce bright red, oranges, and other yellows. Carotenoids are in the foods the bird eats. Pink flamingos would lose their shading if they could not eat carotenoid-filled foods such as plankton, shrimp, or—as handlers at the Philadelphia Zoo have found—carrots.

Other shimmering colorism such as the shiny green of a hummingbird or the peacock’s tail, are produced in part by the shape of the feather. Slight differences in the shape of the barbs break up the light as it hits the feather, producing an array of colors, much like a prism. The colors on the bird will vary depending in the angle from which it is viewed.

Allllll about beaks

Birds don’t just sit in the middle of a bird’s face for decoration. Each bird species has a particular beak shape that helps birds successfully find and prepare the meals they enjoy. Beaks, or bills, have adapted to suit the needs of the birds they serve.

Some birds, including the swallow and whippoorwill, can open their mouths wide. This allows them to scoop insects out of the air as they fly by. Insect-eating birds rarely use their beak in capturing food. That’s why their beaks are almost non-existent.

Seed-eaters, including finches, grosbeaks, and buntings, usually have strong, short bills with sharp edges that help them crack open shells. One of the strongest seed-eater beaks is that of England’s hawfinch, which can crack open cherry pits.

Most ducks have broad, flat beaks that help them take in mouthfuls of muddy water. Then they can strain the water through the beak’s edge, which has rows of bristles lined up like the teeth of a comb. Horny projections from inside the lining of a duck’s mouth allow it to sort what it can eat from the mud,

Spoonbills have long, flat beaks that they hold a slightly open and shake from side to side in shallow salt marshes and coastal waters. They close their bill quickly when something edible floats by.

Storks, with their lanky legs and long, thick bills, get their meals by picking through marshes and damp fields. Their bills allow them to catch and kill snakes, frogs, and insects.

Birds of prey, such as the peregrine falcon, buzzard, and eagle, have a hooked tip at the end of their beak that helps them tear apart meat. They usually hunt for food from a perch or by flying above and quickly swooping down. Owls—most of which eat rodents—also have this hooked beak.

Puffins have short beaks that can grasp small fish tightly. A bright covering grows over the male’s beak in early spring, making it look larger and allowing it to appear more attractive to female puffins that are ready to breed. Puffins shed the covering after breeding season.

The thin, sharp bill of a woodpecker helps it poke into trees’ tiny crevices for insect larvae. Sometimes woodpeckers wedge pinecones into tree bark crevices so that they can peck out the seeds.

 

Early Birds :)

Which came first? The chicken or the dinosaur? There hasn’t been a clear model of a birdlike creature evolving through the ages into the birds we see today. Yet, there have been a number of predecessors whose features clearly think them to modern birds.

In the late 1800s, Charles Darwin’s friend Thomas Huxley made the radical suggestion that birds are actually glorified reptiles. Recent discoveries have convinced many palaeontologists—scientists who study fossils—that this may be true. That means that dinosaurs, which disappeared 65 million years ago, and birds share a common ancestor.

225 Million Years Ago—According to recent discoveries, Protoavistexensis may have been the earliest bird. It had a wing structure that was far more advanced and efficient than the next type of bird that evolved millions of years later. Its hand bones show tiny nodes that may have been the location of feathers, although scientists don’t know for sure.

150 Million Years Ago—in 1861, German workmen splitting slate discovered a fossil of a winged, feathered creature about the size of a large pigeon. Scientists believe it probably used claws on all four limbs to climb around in trees and glided from one branch to another by using its feathered wings and tail. The fossil was named Archaeopteryx lithographica, which means “ancient wings written in stone.”

120 Million Years Ago—Many call Archaeoraptorlioningensis the strongest example of the “missing link” between dinosaurs and birds. In October 1999, scientists unveiled one in the form of a fossil. This foot-long dromeosaur belonged to the same family as the Tyrannosaurus rex.

80 to 85 Million Years Ago—the meat-eating dinosaur Velociraptor is thought to be another link in the evolutionary trail to modern birds. Like today’s birds, velociraptors had three functional toes, long arms with three-fingered hands, and half-moon shaped wrists for seizing prey. Velociraptor may have been covered in feathers—meaning that raptors in the movie Jurassic Park might have felt a little naked.

68 Million Years Ago—Like the Archaeoraptorlioningensis, the huge meat eater Tyrannosaurus rex was a dromeosaur. This shared family has led some to conclude that the T-rex’s young may have been covered in feathers, which they later lost. While these feathers may not have been used for flying, they would have helped in scaring away enemies. It seems the female of this species may have been larger than the male.

65 Million Years Ago—Most species of dinosaurs became extinct. Many of the bird species that had developed died out with the non-feathered dinosaurs. Also, the first modern birds, called the neornithes, developed. During the next few million years, the number and different kinds of birds increased astronomically—leading to the amazing variety of birds we have today.

54 to 38 Million Years Ago—The giant, flightless Diatrymasteini stood at 7.2 feet (2.2 meters) and wandered the forests of Europe and North America. And the direct ancestor of today’s vultures, Eocene neocathartes, soared through the skies. The rest of the neornithes continued to increase in number and variety.

Today—Many scientists believe modern birds are like feathered, short-tailed dinosaurs. Yet, birds have smaller jaws and no teeth. Their tail bones fused together and their forelimbs have changed into wings. And the size of their hind limbs has increased to help them walk on two legs. Migrating and nesting in trees also seem to be characteristics their dinosaurs ancestors did not have.

 

Birds!

On Birds:

Over 150 million years ago, huge flying reptiles, called pterodactyls, sailed across the sky. One of the largest was the pteranodon, which had a wingspan of more than 27 feet (8 m). That’s about the size of a large mobile home.

 

These giant meat-eaters of the sky would have paid little attention to Archaeopteryx lithographica, a delicate flying reptile. It had the teeth and tail common to many reptiles, but its wings had a new kind of covering called feathers.

 

Modern times have seen the extinction of the giant reptiles of the sky, but Archaeopteryx evolved into an entirely new class of vertebrate—birds. Besides having feathers, birds differ from reptiles in a few other ways. Unlike their reptilian ancestors, birds have no teeth. They are also warm-blooded, which means they can regulate their body temperatures internally. Ye birds can relate to their ancestors in one way: they have scales—but only on their legs.

 

Today, there about 9,000 species of birds in the world, from the graceful Caspian tern you see here, to the tiny ruby-throated hummingbird, to the flightless ostriches of Africa—that can weigh as much as three average seventh graders put together. Obviously, birds are a highly evolved group of animals with amazing adaptations.

 

LIGHT BONES

 

Most birds have hollow bones. Bone tissues are arranged as a network of interlaced bone strands. This allows bird bones to be as light as possible, yet still strong enough to provide support as birds glide. This is an adaptation for flight. Flying birds need to shift their center of gravity from their hind limbs when they walk to their wings when they lift off. Of course, birds that are adapted for running have thicker bones that provide greater support.

 

FEATHERS

 

This skin covering is unique to birds. Birds usually have two kinds of feathers; contour feathers, which are large, sleek, and aid in flight, and down feathers, which are smaller, fluffy, and provide warmth.

 

MUSCLE

 

Birds have evolved in special ways for flight. A bird’s breastbone juts outward and is connected to strong muscles that allow the bird’s wings to make the powerful downward thrust necessary for flight.

 

BEAK

Because birds lack teeth, their bills have evolved to perform feeding activities. The variety of bills is astounding. This Caspian tern has a bill modified for catching small fish. But a pelican, which catches large fish, has a bill that is simply a huge scooper.

 

NESTING

 

Birds generally show highly developed parental care of their young. All birds lay eggs, which are usually cared for in the nest. After hatching, some young can fly immediately, though most babies need extended parental care. Caspian terns lay eggs right on the beach, and thus must guard them from the many enemies seeking a meal.