.... So, as the summer has progressed, I've seen several of these small SMB, maybe 6-8 each time I've walked around the pond. Today I seen 5-6, and in 2 months they are still less than 2" long (the problem), which brings me back to Bill's article indicating the lack of available food tends to show up in what I am seeing. Why are my BGxRES and RES present from 1" up to 2.5" in really good numbers and appear healthy?
Snipe, it is normal for LMB growth (even fry survival to advance fingerling) to be greatly diminished by the presence of large numbers of juvenile lepomis (especially bluegill). It is probably also true of SMB. So I think you have a bumper crop of RES and BGxRES at the same size as your SMB YOY. It is competition that is slowing the growth of YOY SMB. These YOY both SMB and RES serve as food for your larger SMB and so I would think the story surrounding your mature SMB is probably a very good one.
This may sound odd, but I do think that crayfish also compete with juvenile fish by denying them organisms of the benthos they would either actively forage or have opportunities for when emerging. Your efforts this year on crayfish removal will serve you next year. It may need to be an ongoing effort in combination with a slot to allow a population of large SMB to develop. These larger SMB should not be harvested as they will be control for your crawfish population. You may consider single sex, very large > 5lb CC as crawfish control as well. One thing I will mention that I might receive criticism for, is that for an ecosystem to work at its greatest efficiency, all the participants need to be working hard for their living. For example, if CC dominate at feed time and are getting sufficient nutrition from feed, it is not likely they are functioning well as a crawfish predator. Let them be a little hungry ... and they will hunt ... this I can assure you.
I know a 2 month old 2" SMB indicates a problem but I can't manipulate forage anymore than I have. Removed over 400lbs of craws that obviously reproduced, small fish everywhere, culling high numbers of most numerous sizes of SMB to make room. Extensive aquatic habitat work that has produced about a 15% area of nursery for YOY.
What am I missing?
I don't think you are doing anything wrong but would suggest that you are experiencing a normal progression that deals with the population dynamics of your panfish and crayfish population. IMHO it will be through management of the panfish and predators that will best serve your goals. There are a number of players in the ecosystem and so isn't as predictable as it could be with a simpler food web. But you have considerable knowledge and very good sampling data, so we are the students and you are teaching us.
We like variety in our ponds and this generally greatly increases the opportunity to grow larger predators. But in small bodies of water, larger predators are usually a sign of diminished growth per individual forage fish than is possible. So having large predators usually comes at the sacrifice of having large panfish, especially over the long haul. The vice-versa can also be said. I think what we want (and try) to do is have the best of both worlds and not sacrifice anything. I would just say that the conditions that favor the growth one population or another are very strong and difficult to overcome. For LMB growing under similar conditions, they are able to achieve trophy sizes because they live a long time. LMB at 4 years age may only be 14" long and may have been only 4" long at the end of the first year, however, they live long enough to "turn the corner" and be a predator of the prey they competed against in the first years of their life.
