I'm glad this progressed to the number of spawns. I have been thinking(uh oh), if some of the several spawns in southern ponds could be impeded, especially in light of first spawns being of the fittest, could we have a better overall pond quality by sabataging some spawns?
Could this be done by timely lowering of water and introducing colder water; not enough to stress the entire community, but to decrease nesting activity? Has this been researched; does it sound feasible?(small pond)