The seabird population on a small British island off the coast Devon and South Wales has increased quickly following the removal of rats.
There has been a growth in the numbers of Manx shearwater, puffins and guillemots on Lundy Island 15 years after a conservation project to remove its rats ended. The project was launched 'in 2003 by the Landmark Trust, the National Trust and The Royal Society for the Protection of Birds （(RSPB）) ）, and aimed to kill the rats because they were the biggest threat to the survival of the birds. A cull （选择性宰杀）costing 50,000 pounds was used to get rid of 40,000 rats on the island when puffin numbers fell to fewer than 10 pairs.
Helen Booker, senior conservation officer for RSPB in south-west England, said the organization is delighted with the results. w This study clearly shows how quickly and positively seabirds respond to the removal of non-native predators （捕猎者），" she said. "Of course, we had expected major population increases when the project was launched, but the scale of this recovery has far beyond our expectations."
Dean Jones, the inspector on Lundy, which is managed by the Landmark Trust, said the recovery of the seabirds was a positive, but that it is important to remain cautious・"It is exciting to see this level of recovery in Manx shearwaters, one of our most important seabirds. In spring the island comes alive at night with the sound of these amazing birds. The increases in puffins, guillemots and razorbills are also very encouraging for the future of seabirds on Lundy and we are maintaining our attention to ensure rats cannot return to the island. "
A recent study found that nearly 10 percent of endangered bird, mammal, amphibian and reptile species could be saved by culling invasive （入侵的）mammals such as cats and rats on 169 islands. But rat removal programs have been controversial with some animal rights activists, who have argued that the black rat is one of the country's most endangered mammals.
28. Why did British carry out the project to remove rats?
A. To kill invasive species. B. To save seabirds in danger.
C. To keep balance in nature. D. To decrease the rat's number.
29. What can we infer about the rat removal project?
A. It is favored by animal rights groups.
B. It started when guillemot is nearly dying out.
C. It has protected 10% of species on UK's 169 islands.
D. It contributes to more increases in seabirds than expected.
30. What will be done next according to Dean Jones?
A. Plan the future of seabirds. B.Speed up the recovery of seabirds.
C. Keep a careful watch for rats. D.Continue to drive away rats and cats.
31. Where is the text most likely from?
A. A news report. B.A research paper.
C.A biology textbook. D.A medical magazine.
答案 28.B 29.D 30.C 31.A