Good idea about the sentinel bird, in my ponds I call them sacrificial goldfish to test and condition the water for koi. I don't have any original birds as they were all given to me from 4 different family's who probably got them for Easter last year and thought they were going to get instant egg dispensers, I got them all within 5 days time. However I will not be adding anymore until I am sure these are healthy and will build a temporary holding pen for additions.
