Good points all!! From what I have gathered so far there seem to be a number of factors like type and size of predator , time of day stocked ,amount and length of light left in day , water temp. ( predator metab./time of year), thickness of cover, size of stockers and their conditioning as to predators (have they seen them before)and others. Bruce I have seen the same slaughter wrt new stocks of small BG ,RES, tshad, trout and tilapia and it is not a pretty sight if you are paying for the new fish. ewest