translation.en: And if we look at a very pristine environment like western Australia, Lars Bider has done work comparing dolphin behavior and distribution before there were dolphin-watching boats.
translation.zh: 让我们看看像澳大利亚西部这样一个非常原始的环境， 拉尔斯.比泰尔曾 比较了观海豚的游船产生之前和之后， 当地海豚的行为和分布。