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8、A．Why kiwis are flightless

B．Preventing the kiwi decline

C．Reasons for concern

D．Explanations for large bird populations

E．Land of the kiwi

F．Te introduction of predators

1．        The kiwi is the national symbol of New Zealand and Australians endearingly refer to New Zealanders as “kiwis”---People from the Land of the Kiwi. This unique bird, recognized by its short squat body and elongated beak, is under threat. Its small, claw—like wings make the kiwi flightless, so it has to live on the ground. The kiwi is thus easy to be victim of enemies such as humans and mammals.

2．          When great landmass of the south split 75 million ago, the kiwi and many other ground—living birds became separated from predatory mammals within what was later to become  known as New Zealand. The birds were able to multiply and flourish because there were very few mammals landlocked within the islands. Kiwis have evolved certain mammalian characteristics as time went on, living on the ground and they were free from attack by mammals.

3．          However, when the Polynesians arrived about 1000 years ago bringing with them dogs and rats, the kiwi population and other vulnerable bird species soon suffered a severe reduction in numbers. The coming of the Europeans in the 18^th century brought even more determined predators, including the cat and, especially,  the stoat, which is a very vicious and powerful killer of kiwis.

4．           There are six types of kiwi, and all six are threatened. Two are ‘critically endangered’ because they have populations of less than 250 mature birds. Two are ‘endangered’ meaning that it is estimated that within three generations their numbers will have declined by 50%. The other two are ‘vulnerable’—one because its habitat is shrinking, the other because it is potentially under threat from stoats and other mammals.

5．             100 years ago there were more than 5 million North Island Brown Kiwis. Today, there are probably around 30,000 , and the population is decreasing at a rate of 6% a year. Only the Little Spotted Kiwi is increasing because of successful attempts to transfer the creature of predator—free offshore islands. There are further reasons for hope. Trapping predators and rearing baby chicks for later release into the wild can have a dramatic effect on kiwi numbers; but it will be necessary to do so on a large scale.