GRE Reading Comprehension: JiJing 352-GRE阅读机经352篇 - MU7FTPI2PG8WN7ZTK

Sportfishers introduced the Zander, a type of perch, to Britain's rivers and canals in the 1970s. Because zander eat large numbers of smaller fish, they have had a devastating effect on native fish populations. To protect the native fish, a government program removed a significant proportion of the zander from Britain's waterways last year. Surprisingly, this year the loss of native fish to zander has been greater than before.