The lecture and reading passage hold different positions respectively on the issue of Zebra mussels. The lecture's argument is formed around many points that are in direct contrast to the materials in the reading passage.
First off, the reading passage suggests that zebra mussels pose a threat to ecosystems because the population of zebra mussels easily skyrockets due to the lack of natural predators. However, the lecture rebuts this point by claiming that the increased number of zebra mussels will be eventaully checked. This is because, after being used to zebra mussels, birds begin to recognize zebra mussels as food source. This will control the population of zebra mussels thereby removing the threat to ecosystem.
Also, the reading passage claims that the emergence of zebra mussels can negatively affect native fish since they eliminate nutrients by consuming living organisms like plankton in the water body. On the other hand, the lecture refutes this point by claiming that the population of native fish will expand in contrast to the reading's argument. The reason is that zebra mussels remove polluted water by filtering pollutant. As a result, fish which rely on the quality of water will thrive more and fish live in deep water will be able to obtain more nutrients.
Lastly, the reading passage argues that people cannot stop the transfer of zebra mussels because cargo ships use lake and river water which include zebra mussels as their ballast water. In contrast, the lecture counters this point by arguing that people can solve this problem easily by making cargo ships use sea water instead of fresh water. Then, zebra mussels will naturally die off in cargo ships because they cannot tolerate salty water.
In conclusion, the reading passage presents three aspects with regard to zebra mussels. However, the lecture's argument makes it clear that none of these points justifies the reading passage's suggestion.