I came home from driving our semi over the road to find 140 dead and dying BG. Check out this thread http://www.pondboss.com/cgi-bin/ubbcgi/ultimatebb.cgi?ubb=get_topic;f=20;t=003668 and you will get a wealth of information that these wonderful people guided me with! My "stressor" turned out to be Merganzer fish ducks, the coyote of the bird family, along with the other fact mentioned above, in that I need to feed more and feed later in the year. I think you will find all the help I got exactly what you are looking for.