This all makes sense. Considering how far north I am, I've ruled out fertilization, which makes pellet feeding even more necessary to support a fairly high density of medium to fairly large predators. I imagine I'd have to pay attention and back off pellet feeding at the first sign of increased FA, weed growth or a really nice phytoplankton bloom after Spring, and I think I'd stop feeding completely for a while if I saw plant growth plus high numbers of YP YOY in my sampling (via trapping, angling, and what I see during feeding) in the hopes that the bigger YP and other predators if stocked would get hungry and decide to work for a living (i.e., eat the YOY).
in some studies from 4 to 8 times more efficient than natural food (fish don't have to chase down pellets and there are no bones , skin and scales to digest)
This is a great insight that I never thought about before, but that makes a lot of sense intuitively.
Regarding controlling spawning via removing egg ribbons:
My feeling is that this should be a cornerstone of the management strategy for this type of pond. Limiting YP numbers from birth would reduce their pressure on the natural forage base, allow less competition and faster growth from the start, and reduce or possibly eliminate the need for larger predator species. Fewer (or zero) other predator species simplifies things a bit, I'd think. Less pressure on the forage base, fewer mouths sharing pellets (so fewer pellets needed, which means less risk of degrading water quality), less accidental predation on the harvestable size YP, and less BOD.
I'd plan to put out a significant number of shoreline branches to be able to access and thus control as many of the ribbons as possible. Just naively, I'd think 1 fertilized ribbon each year per 1-acre might yield enough YOY to eventually replace those harvested in a pond without another predator species, considering some natural mortality and predation by larger YP (if pellet feeding to distract them a bit from YOY), but removing all except for 1 ribbon seems to run the risk of that particular lucky ribbon not being fertilized and thus missing a year class. This would get especially risky if we harvest males heavily, I'd think. So, I'd probably err on the side of leaving 2-3 ribbons each year per acre, knowing that that means I'd probably have to trap out quite a bit of the YOY most years or stock a few WE or other predator.
Bill, so last year you trapped out 509 YOY in a 0.6 acre pond, or about 850 YOY per acre in your pond without other predators beside larger YP. Did you remove any egg ribbons last year, or was that the result of just letting their reproduction go naturally/untampered with?
