I agree with Cody.
Cecil saw tons of FHM in his large pond with a healthy population of large YP in it.
Many times I field phone calls from people that fear that they don't have fish in their pond, or that they don't have enough fish in their pond. When the water changes temperature, or when they switch angling tactics, they start seeing or catching fish.
I received a phone call from a fish grower last year. He seined his pond 8 times and was sure that he got all the LMB out of his pond. His fish supplier said that unless the pond was killed with Rotenone, he would not furnish the LMB fingerlings to stock the pond (the grower was growing LMB on contract - he was just furnishing the pond and the labor to feed the fish).
Not only did fingerling LMB float up when I applied the Rotenone, (the LMB spawned at 1 year old, even when stocked at the rate of 5,000 fish per surface acre) there were 10" YP that came up, 3"-4" YP that came up, three 2# - 3# LMB that came up, and this LMB. Now, how did this LMB evade the seine that many times??
Pond owners have to remember, that even though the pond is a fixed size, there is still a LOT of area in a pond for fish to swim in, and then even if you find them, you still have to convince them to bite a baited hook. I can't tell you how many times I've sight fished, dropped a bait (either live or artificial) in front of a fish and they wouldn't open their mouth to take it.
It's my belief that there is no way that you fished all the YP out of your pond.
Regarding that LMB in the picture. Not only did it evade the seine numerous times, it was still able to swim fast enough to catch food, and grow. I think that the fish was stocked that way - the LMB were stocked in the pond 27 months prior to the Rotenone application. Previously the owner grew YP and did not rotenone the pond prior to stocking the LMB - he thought he seined all the YP out of the pond. There were maybe 10-20 YP that were 10"-12" that came up, and a couple hundred in the 3"-4" range when the pond was rotenoned. No other fish species besides those YP and the LMB.