3 . Macquarie Island is a tiny island that’s part of Australia. It’s about halfway between New Zealand and Antarctica. The island’s been made a world heritage area because it’s so untouched, but this unique environment is under threat from some unwanted visitors.

It all started when seal hunters came to the island in the early 1800s. They brought rabbits with them as a source of food for the journey, and also on board the ships were rats and mice, which made their way onto the island too. They’re being blamed for destroying the homes of marine birds, causing soil loss and ripping up plant cover, as these before-and-after photos show.

So what’s being done about the problem? It starts with a team of helicopters that fly across the island carrying these giant containers. Inside them are poisoned pellets (有毒饲料) which are dropped and spread across the island. For any rabbits that survived the baiting (诱饵) , there’s a plan B. This special team of dogs is being put through a final training. It’ll be their job to track down any remaining rabbits. They have to also learn to behave around the island’s native wildlife. The dogs could be here for years or until the task is complete. The dogs don’t actually kill the rabbits. They find them, then the hunters decide to either catch the rabbits or shoot them.

But the program has received a bit of criticism. Some people argue 25 million dollars is a lot of money to be spending on wiping out rabbits and rodents (啮齿目动物), and in the process, some native birds will be killed because of the baiting.

The reality is the problem isn’t going to be solved overnight. The people running the program say that even if one pair of rabbits is left alive, the whole task will be seen as a failure, which means these guys could be here for a long time, trying to ensure that this precious island remains protected from pests.

The conch (海螺) is       1     (wide) considered to be the national dish of the Bahamas. Queen conch is one of important food materials and can live for 30 years.

Conches can be very     2     (expense) in the U.S. and other places. But it is so common in the Bahamas     3     it can often be found in meals costing     4    (little) than two     5     (five) of the population in rural (农村的) parts of the Bahamas eats conches weekly. The country of about 400,000 is home     6     9,000 conch fishers-around two percent of the population. This number appears to be holding steady even as conches decrease (减少) in number. For many fishers here, fishing is both a family tradition     7     a path to middle class life. The meat of the conch     8     (be) worth millions of dollars per year, and it also helps increase tourism to     9     islands.

The conch is one example of the threat (威胁) overfishing presents to traditional foods around the world. Similar problems     10     (see) in Senegal now, where overfishing has taken away white grouper. The fish has long been the basis for the national dish of thieboudienne.

Imagine that you’re sleeping in the wild in a tent and are awakened by the sound of wolves howling(狼嚎叫). That’s     1    happened to me last summer when my family and I spent the night at the Wolf Conservation Center (WCC) in South Salem, New York. The howling didn’t frighten me. Wolves howl to communicate     2    each other.

The WCC educates people about wolves,    3    (they) relationship to the environment, and how to ensure that they survive. Guests     4    (invite) to visit the wolves year­round. The center is home to twenty­five wolves and two    5    (serious) endangered species—the red wolf and the Mexican gray wolf. At one point, both species     6    (be) extinct in the wild. With help from the WCC, the wolves are making a comeback.

“Wolves help to keep all other animals in balance(平衡) and keep the environment really     7    (health) ,” said Mary Kate Kabbes, an educator at the WCC.

When wolves became extinct in Yellowstone National Park, the elk(麋鹿) population increased to five times its normal(正常的) size and destroyed areas where birds lived. As    8    result, several bird species were forced to leave the park.

Now that wolves are back at Yellowstone, the birds have returned. “Learning about wolves, reading books about them, and telling your family and friends is a simple way    9    (help) spread the word about the     10    (important) of wolves.” Kabbes said.