Quote:
I must be stupid,
If some charts show the 8 yr old biomass declining.
And some charts show total biomass climbing.
Does that imply more small fish and less bigger fish ?
|
My interpertation is that the larger fish biomass is steady (in fact it has shown a tendency to increase); that is mostly due to the huge spawning classes (1993-2005 Attachment 1)...those fish have been growing (and caught), but there were such huge spawns those years that they created a very large pool of fish...thats why the F index is still high; remember that the YOY was started in 1950 (started tracking in 57), and has shown up and downs (as most life cycles do). I think the SUPPOSED shortage of small fish (I haven't seen it in my time on the water-which is often) may be caused by the increase in rec targeting, and the increased commercial quota to net fishery in the Chesapeake (DE, MD, PRFC, VA, NC) several years back. I think that because the spawning biomass is so large, the F index is above what ASMFC considers proper to sustain the viability of the species....it is a very hard thesis for a layman (that's me) to follow, a lot of these scientists working for ASMFC have dedicated their professional careers to study the fishery. For me, I have to place my trust in something, and my 40 years on the water has shown that the fishery is a lot better than in the late 70's...(though I still caught then)....so I have faith in their postulations.....