decreasing number of birds in the United States

The reading and lecture are about the decreasing number of birds in the United States due to the increasing human population—the author of the passage doubt on reasons which affect bird populations in urban areas. On the contrary, the lecturer contradicts various viewpoints mentioned in the passage based on three reasons.
To begin with, the professor totally not rejected the point that human habitation could have a negative effect on birds' settlement. She brings out the idea that urban areas have a bad effect on some types of birds, but it is the best habitat for other species like Huks and Pigeons.
secondly, the professor accepts the point that agricultural activities have an influence on birds' population but, she also mentions that it does not occur on the way as soon as the author writes in the passage. Additionally, she asserts the idea that agricultural activities get less and less every year that past in the United States yet they introduce a new variation of crops which does not need to destroy the areas.
In the end, the professor cast doubt on the idea in the passage that using chemical pesticides, which affects the water and also destroyed some species of animals and insects that, are necessary for birds. Hence this phenomenon has a negative effect on the bird supply chain. According to him, new genetic developments that accrue in crops help them to use fewer chemical pesticides. However, new and much less toxic pesticides have been developed.