Well thats ur opinion some people might not think it is hard
Answer:
sorry if my answer is incoplete.
From my speculation it is loss of habitat and global warming
While relative humidity is (as its name suggests) a relative measure of how humid the air is, the dewpoint temperature is an absolute measure of how much water vapor is in the air. In very warm, humid conditions, the dewpoint temperature often reaches 75 to 77 degrees F, and sometimes exceeds 80 degrees