ALL ABOUT BIRDS
Birds are warm-blooded vertebrate animals that have wings, feathers, a beak, no teeth a skeleton in which many bones are fused together or are absent, and an extremely efficient,, one-way breathing system. Flying birds have strong, hollow bones and powerful flight muscles.
Most birds can fly. Birds have a very strong heart and an efficient way of breathing - these are necessary for birds to fly. Birds also use a lot of energy while flying and need to eat a lot of food to power their flight.
Not all flying animals are birds; and not all birds can fly. The ability to fly has developed independently many times throughout the history of the Earth. Bats (flying mammals), pterosaurs (flying reptiles from the time of the dinosaurs), and flying insects are not birds.
MOVING: Flying, Running, and Swimming
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The fastest running bird is the ostrich, but it cannot fly. The ostrich is also the fastest two-legged runner of all the animals on Earth. The ostrich is the largest bird. |
Bird locomotion is quite varied; most can
fly, some can run very well, some swim, and some do combinations of these. Some
birds
cannot fly.
Most birds can fly. Flying birds' wings are shaped to provide lift, allowing
them to fly. These light-weight animals have adapted to their environment by
flying, which makes them efficient hunters, lets them escape from hungry
predators (like cats), and takes them away from harsh weather (migration).
The peregrine falcon is one of the fastest birds, and has been clocked at 90
miles per hour in a dive (and some people say that they can dive at
over 200
mph).
Feathers:
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Male birds are frequently more brightly colored than females. This is to attract females for mating purposes. The females are more dully colored, helping to camouflage her when she is caring for her young (although the male often cares for the young, with or without the female). The peacock (the male peafowl is pictured above) is very brightly colored. The peahen (the female peafowl) is dull brown in color. |
Feathers are highly modified scales. There
are different types of feathers that have different uses.
Feathers are used for:
Diet:
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Some amazing hunters, like eagles, have eyesight that is five to six times sharper than a person's. They can spot small prey from a mile away. |
Modern-day birds do not have any teeth (ancient birds did have teeth). Birds have a tongue, but unlike our tongue, a bird's tongue has a bone in it.
Birds spend most of their time looking for food. Most birds are insectivores (they eat insects). Some birds, like owls and eagles, are carnivores (meat-eaters). Some birds, like the hummingbird, grouse, and Canada goose, are mostly herbivores (plant-eaters). Other birds, like starlings, are omnivores (plant- and meat-eaters). Some birds (like the toucan) are fructivore (fruit-eaters)
Birds mostly use their keen eyesight to find
food. They use their beak and their claws to get bugs, worms, small mammals ,
fish, fruit , grain, or nectar.
Birds play a very important part in the natural control of
insects and in the dispersal of seeds. Some birds, like the tiny,
nectar-eating
hummingbird are important pollinators of some
flowering
plants.
Nests and Eggs:
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Birds bear their young in hard-shelled eggs which hatch after some time. Some birds, like chickens, lay eggs each day, others (like the maleo) may go for years between laying eggs.
Birds
build
nests for breeding in trees, on cliffs, or on the ground. Most birds are
taken care of by at least one parent until they are able to fly and get their
own food.
|
Bird |
Incubation Period |
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20-22 days |
|
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42-50 days |
|
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Parakeet (budgie) |
27-28 days |
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14-18 days |
|
|
30 days |
|
|
18 days |
The incubation period of bird eggs varies from species to species. There's also some variability due to the temperature.
Some birds, like old-world cuckoos and some cowbirds, lay their eggs in other bird's nests. The non-related adult bird takes care of the cuckoo's egg unwittingly. Some cuckoos even kill the other eggs in the nest to insure that their egg gets enough food.
Migration:
Many bird species migrate to a cooler
climate for reproducing and summer feeding, and then return to a warmer climate
for the winter. It is unknown exactly how birds are able to
navigate
accurately, but many people are studying this mystery of how birds know
where to fly.
The Classification of Birds:
Birds
belong to the biological class
Aves and
live virtually everywhere on Earth. Birds are amniotes, animals whose eggs are
protected from drying out (a group that includes the
mammals, birds, dinosaurs, and reptiles). There are about 9,000 different
species of birds, divided into
24 orders
and 146 Families. Most birds alive today are
Neognathae
(a group distinguished by common palate structure). Another, much smaller group,
is the
Palaeognathae (again grouped by palate structure), which includes the
ostrich,
kiwi,
emu, rhea, and others.
The Evolution of Birds:
Birds
probably evolved from meat-eating (theropod)
dinosaurs during
the
Mesozoic Era, roughly 150 million years ago. Early birds, like
Archaeopteryx, had teeth in their mouth and claws on their wings.
Bird Songs:
Birds sing beautiful and diversified songs. Many songbirds are becoming
scarcer every year.
Songbirds have a vocal organ called the
syrinx located in the throat. The muscular syrinx has two halves that each
vibrate to produce songs, so the bird can sing two notes at a time. To sing, a
bird blows air from the lungs through the syrinx.
Do Bird Have Knees? Why Do Their Legs Bend
Backwards?
Yes, birds have knees (they're often under the feathers and not easily visible),
and they bend the same way our knees bend. The part of a bird's legs that bends
backwards when it walks is the ankle.
Heart Rate and Breathing:
In order to fly, birds need a lot of oxygen, which they get by breathing air
using lungs. They also need a strong circulatory system, including a powerful
heart in order to circulate the oxygen. A bird's heart beats much faster than
our heart does. A hummingbird's heart beats about 1,000 times each minute; a
human's heart beats about 60-90 times each minute.
Birds breathe using a unique system in which air follows a one-way route through
the respiratory system. This system is unlike our lungs, in which the air
backtracks where it came from. Their system of respiration (breathing) is very
efficient - much more efficient than our system.
Birds have two relatively small lungs (where gas exchange occurs), but the lungs
are augmented by bellows-like air sacs (where no gas exchange occurs). These air
sacs keep the lungs perpetually inflated (even when the bird is exhaling). Our
lungs alternately fill and empty out. The bird's respiratory system takes up 20%
of a birds's volume (our respiratory system takes up only 5% of our volume).
In the bird's respiratory system, air first flows through air sacs (located even
inside their hollow bones) that direct fresh, oxygenated air into the tube-like
lungs (parabronchi, where gas exchange occurs) both when the bird inhales and
when it exhales.
This system increases birds' respiratory efficiency and gives them enough oxygen
for flight.
Why Can Birds Perch on Power Lines?
Birds can often safely perch on a power line without being electrocuted. For the
bird (or other animal) to be electrocuted, a potential difference must exist
across two points of the bird's body (its feet in the case of a bird on a power
line). When perching on a single power line, there is no potential difference
between the bird's feet, so it is safe. If the bird (or other animal) touches
two power lines at a time, or one power line and a ground (like a ground wire or
the earth itself), the animal would be electrocuted and die. Many large birds
(like eagles and vultures) are electrocuted when their wide wings touch a power
line and a ground wire at the same time (often while flying in to land on a
power line).
This is why it is VERY unsafe to fly a kite
near power lines. If the kite gets tangles in the power lines, the kite string
acts as a ground, and you can be electrocuted.
Click here to learn all about bird extremes: the biggest bird, the smallest, the
bird with the longest beak, and much more.
BACKROUND
There are less than 800 Cape parrots (Poicephalus robustus) left in the wild. The reasons for their low numbers are as follows (Wirminghaus et al.1999).
The above reasons make it important to understand the biology of the Cape parrot to help manage wild populations .The breeding observations in this text was made on the northern race (Poicephalus fuscicollis suahelicus) and will help to understand the breeding biology of the Cape parrot.