Answer: There is pollution in the east river
Explanation: If we think about it cant be a lack of food as it talks about having a large food source. Nor can it be climate change as that would result in a low yellow Perch population. it cant be they aren't able to catch the bird. So the only logical answer is a pollution that the birds are adapted to.
D is the correct answer. I just took this quiz not too long ago and got it right. Hope this helps
Although there are many global issues that are a primary threat to <span>biodiversity in the tropical regions of Central Africa, Southeast Asia, and the Amazon basin the best answer is "deforestation". </span>