Which of the following do researchers think is primary factor in the decrease of North American bird populations is it decrease hunting of predators, species changes and farming practices, such as draining, wetlands, and pesticide, use recreational, hunting, a bird species, such as waterfowl, or a decrease in conservation a efforts
Researchers believe that the primary factor in the decrease of North American bird populations is species changes and farming practices, such as draining wetlands and pesticide use.
