Turns out you were right...there are fewer birds. We have killed millions of them by using toxic sprays for pesticides and herbicides...and we have over developed nitrates in their natural foodstuffs...which have provided toxic nitrates that add sugars to the seeds and plants...and poison to them as well.
But it is even more than that... man, from his earliest migrations, has been accountable for the destruction of species after species...only the most visible are our feathered friends. The ivory billed wood pecker is one example of this...here in America we have eliminated this bird through habitat reduction alone...the last sighting being in the 1960s...when once it was among the most populous birds in the South East of the United States.
