The sea otter is a small mammal that lives in waters along the western coast of North America from California to Alaska. When some sea otter populations off the Alaskan coast started rapidly declining a few years ago, it caused much concern because sea ot

Both the reading and the lecture discuss about the environmental and the predator theories. These two theories might help explain the decreases in otter's population. Whereas, the reading passage claims that the most important one is the environmental, the listener opposes and says that predator theory arguments outweigh the others.

In the first place, the article explains that some pollution sources have been found around this area. On the other hand, the listener claims that investigators didn't find sings in dead animals that may prove infection or contamination of being responsible. In addition, predators might be responsible for some dead bodies in the river. Also, traces of being attacked by whales were discovered.

Second, the article posits that other animals such as sea lions have decreased, so, this shows a wide ranch of water contamination. Nevertheless, the speaker says that whales are the principal predators in this zone, and they have changed their food preferences. before they preferred big preys such as other whales, but now they choose to hunt lions and otter because big preys no longer exist in this area.

Finally, in the article the author claims that a declining pattern have been noted in animals of the region. So, this indicate that water is more loaded with chemical substances in some areas than others. Contrary to this point, the listener explains that the orca is responsible for these patterns because they have greater access in some regions than they have in others. So, more room to swim and hunt.