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Hoot Hoot
A biology project on Owls.
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 Hoot
Owls.♥A 2011 biology project on owls! This blog is a biology project on owls. It is about the basic understandings about them. It includes characteristics, reproduction, internal systems, such as respiration, of an owl. Hope you enjoy! — Hooooot Parliament
Group members: Bich-Tien Phan (2), Kim KumJo (17), Lauren Wong (19), Sharmaine Tham (32)
predators (bibliography)
12 3 4 5 Archives
August 2011
Credits
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Wednesday, 3 August 2011
OWLS. INTRODUCTION- WELCOME TO SCIENCEFORLIFE101.BLOGSPOT.COM! This is a blog for our biology performance task. :) By: Bich-Tien Phan (2), Kim Kumjo (17), Lauren Wong (19), Sharmaine Tham (32) Hope you enjoy! (Under Mrs.Mohan's Biology Class) Owls The owl is a very special creature. Owls became symbolic of intelligence because it was thought that they presaged events. On the other hand, because of their nocturnal existence and ominous hooting sounds, owls have also been symbols associated with the occult and the otherworldly. Their secretive habits, quiet flight, and haunting calls have made them the objects of superstition and even fear in many parts of the world. General features Owls have a large head and large eyes that face forwards, unlike many other birds. This eye placement gives them binocular vision and a very precise depth perception. Also, there are circles of radiating feathers surrounding each eye, giving them a wide-eyed, alert look. Owls cannot move their eyes within their sockets like we can. For them to look around, they have to move their entire head, which can rotate up to 270°!! Some owls have feathered ear tufts. The colour of their feathers allow them to blend in with the wood on the trees at night. The shape of an owls's body is oval and the feathers on its wings help them fly silently. Their necks also have extra necks. These are not ears but they are a part of the owl's camouflage! For their flying, many owls have thick feathers that absorb the sounds that their wings make while they fly.  Owls are nocturnal birds, which means they sleep in the day and they do everything else at night, opposite from us, human. They hunt at night. They use their sharp eyesight to find prey in the dark. They have an acute sense of hearing which also helps in their hunting. Owls are stealth hunters, they can easily sneak up on their prey since their fluffy feathers give them almost silent flight. Owls have two methods of hunting, by perching and pouncing and quartering. It is able to see mice, skunks, snakes, any creatures in the dark of night. They have incredibily sharp claws and they are able to hear mice running on the ground when the owl is high in the air. They do not turn their eyes, they turn their heads and they tear meat with their long, sharp beaks.They also swallow their pray as a whole then they spit out pellets with bones Owls are mostly found worldwide in a huge range of habitats from rainforests to grasslands, to many other wooded areas. Owls eat smaller prey whole and larger prey in chunks. The owl is at the top of the food web; it has no major predators. This is an Overview of the whole owl- labeled.  (www.owlpages.com/articles.php?section=Owl+Physiology&title=General) Owls can be divided into 2 families, Tytonidae and Strigidae. This includes 16 species of barn and bay owls and 189 species of typical owls. All owls are nocturnal except for the Burrowing Owls that can be found in the North America. The difference between the 2 families of owls, is that the Tytonidae family have heart-shaped faces while the Strigidae have round faces. Singapore is a home to 8 species of Owls. All owls are different although they are in the same family. They live in different habitats and have different sources of food. For example, the Tyto alba, barn owl and the Asio plammeus, short-eared owl live in different habitats and different diets and more. The Barn owl lives in forests, cliffs, wooded areas, buildings and caves while the short-eared owls live in open grasslands and marsh. Next, the Barn owls feed on small mammal mainly like small birds while the short-eared owls feed on small rodents, small birds and large insects. The Barn owl can be found all around the world excluding Antarctica and the short-eared owl can be found all over the world except for Australia and Antarctica. These too owls also live in different type of nests. The Barn owl lives in a secondary tree hole while the short-eared owl lives in a shallow depression on the ground lined with grass and feathers. Here are some pictures of these 2 owls: This is the Barn owl.  This here is the Short-eared owl.  (In bibliography) - This information is adapted from http://kokhuitan3.fortunecity.com/birds/owls.html and http://www.hipark.austin.isd.tenet.edu/projects/second/owls/owls.html Systems in an Owl’s body 1. Respiratory system. The owls follow the same respiratory system as all other birds. In the respiratory system, the bird contains a larynx. The organ which is termed as syrinx, that is served as a voice box however, it is not used to produce sounds. Similar to the mammals, the bird has lungs, but also has air sacs. The number air sacs, seven or nine, depends on the type of bird. The air sacs of birds extend into the humerus, the femur, the vertebrae and the skull. Gas occur in the walls of microscopic tubules called "air capillaries." However, birds do not have a diaphragm but air moves in and out of the system in the air sacs through pressure changes. The reason why the bird has no diaphragm because the air sacs reach into the bone. The muscles in the chest pushes the sternum outwards. In order for the sternum to move during respiration, it has to be allowed to move freely when the bird is restrained. Otherwise, the bird would suffocate. Lastly, the bird's respiration consists two respiratory cycle in order to move the air throughout the whole respiratory system. 2. Digestive System The digestive system of an owl, once again, is the exact same to normal bird species. The digestive system is complex for the size of them. A small bird can eat up to 20% of its body weight daily! Birds have high metabolism rates, so they can keep up with the requirements that they need to have. The system begins with the beak and tongue. Birds have a very strong beak. When a bird eats it uses its beak and tongue to gather food. Since a bird has no teeth, chewing time is eliminated. Since a bird does not have to chew its food they can often eat a large quantity of food at one time. Saliva lubricates the food much like in a human so that it can pass to the oesophagus. The oesophagus is a tube-like structure which passes food in waves better known as peristalsis, to an organ known as the crop. The crop, located at the base of the neck, stores food. Then slowly, the crop will continuously supply small amounts of food down to the stomach. The stomach is the most active part in the stomach. The first part is known as the proventriculus. This is the glandular portion of the stomach. This portion secretes digestive juices to break dow food. The proventriculus joins a large muscular portion of the stomach known as the ventriculus, or more commonly known as the gizzard. The gizzard will grind up even more food. After leaving the gizzard the food Is passed on to the small intestine, mixing the bile and enzymes. The enzymes will help to break down the sugars, fats and proteins. Bile (from liver), breaks down the larget fat molecules. Then the nutrients are absorbed and passed to the blood. A bird’s digestive system is very efficient as it largely depends on its keeping up with its metabolism reactions. Reproduction of an owl Male owls use special call to attract females to their territory. It involves the male and female chasing each other in flight while both call out loudly to one another. The male owls also have a special behaviour called “moth flight”, where the male hovers in front of the female, displaying its special features. Another ritual performed by owls involves the male repeatedly flying from a female’s nest to his own to get her attention. If the females gets impressed by him, it will give a unique mating call. Then the male will bring a freshly caught animal as an offering. Owls usually begin a nesting phase during the mating period. When the mating season comes near, the female will begin acting as if they’re brooding even before laying any. After an egg is fertilized (a day or 2), it goes through several stages of development. The developing egg, which is known as the yolk, it gets several coatings of albumen. It then gets two coatings of a material that forms the familiar hard shell. When it hardens, the egg begins to develop. Eggs are laid individually every 1 to 2 days. During incubation, the female rarely leaves them, except when she has to hunt and get water. To help the incubation, they have feathered brood patch on their stomach that has more percentage of blood vessels. Blood flowing through these vessels will be a great source of warmth for the eggs. Hope you enjoyed our blog! |
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Hoooooot,
“The owl of ignorance lays the egg of pride. |
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