In Wisconsin this has been used for many years as a DNR tool--It helps reduce herds in certain area,s . Example--there are many area,s of private farmland that only gets hunted by landowner , many times these landowners get together to make deer drives in a more efficient way to reduce herd numbers and deer damage. This is one example---it also is a fun way to hunt together as a group and enjoy the camaraderie . If it ever has had a bad impact I am sure it would have been dicontinued