YOu had better NOT take any representations from these so-called studies at face value. In the case of the studies of duck and geese mortality, they had a lab actually put lead pellets ( New- nor fired and picked up in the mud ) down the throats of live birds, in quantities that had no factual comparison to any found in dead birds. They did not take into account that lead oxidizes quickly, that the oxide does not wear off easily, and it does not combine with anything but rather passes through the stomach of geese and ducks rather quickly. It was only in later " Tests" of actual dead birds, that they found most of the lead that made it into their blood systems came from lead shot wounds to these birds, and that rather being a part of some " preventible " mortality of migrator birds, these ducks were part of those ducks and geese wounded, but not recovered by hunters. Those numbers are already factored into the formulas used to determine the length of hunting seasons, the number of birds that can be killed each day by each hunter, the point system assigned to certain species of duck to limit the kill of those species, etc. There is NO preventible mortality of migratory birds caused solely by ingesting lead.
So, be very careful about listening to any of these studies, without reading the studies, and questioning the details. Today, its okay at Universities to first determine what you want to prove, and then set a laboratory model to prove it! ( This is called " Junk Science".) But it gets funding, anyway. ( The Federal EPA, and CDC are notorious for funding such kinds of research, and furthering political agendas with the " results".)
The scientific method demands, on the other hand, that you begin with a proposed thesis( an explanation for how something works, or how a result in nature occurs)< and then you attempt to disprove it. only when everything you can try in your models, and lab experiments fails to disprove your thesis do you write a paper suggesting that your thesis is valid. Then the paper is submitted for peer review by other scientists who are working in the same field, and are familiar with the testing procedures you use, or are available to test your thesis, and they make comments, good, bad, or indifferent. Only then is your paper published. The purpose of this entire system is to rid the scientific literature of Junk Science, and those people who are too willing to prostitute themselves and their labs to produce " results" that furthers some agenda other than science.
