Quote:
Originally Posted by Back Beach
Some people think the fish are on the brink of extinction, and rarely do they cite any scientific data or facts to back up their views. SF comes to mind. If you can, explain what fmax is so people understand, meaning how does it convert to inches when you say they need to spawn at least once? How big would a fish need to be that spawns at least once? The reason I posed the question was to try to shed some light on how this stuff really works. A lot of people might respond "36 inches and one fish a day" because it sounds like a good conservation measure, but might not be able to back it up with good methodology or science. Lets hear some more of the why, if you will.
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Sorry I misunderstood what you were asking for. The stock assessment is the first block in most fishery management decisions. The second step is to decide where you want the stock to be vis-a-vis the current stock assessment. Most times fishery managers don't want the stock to be less that it currently is, so I'll discount that possibility. More usual is that the managers want the stock at about the level it currently is (which IMHO is where the striped bass stock assessment will come in) or they want the stock to increase. "F" stand for fishing mortality. When a fishery management plan is adopted (FMP) it usually calls for a target biomass in a given timeframe, if rebuilding is required, or it calls for holding the biomass steady, if no rebuilding is called for. Fmsy ifs the fishing mortality that the stock can stand and still maintain the Maximum sustainable yield (MSY) which is the way the U.S. has decided that all rebuilt fisheries should be managed. To convert Fmsy to coastwide bag limits, one has to estimate the number of fishermen and divide the msy by the numer of fishermen and fishing days to come up with the bag limit. Stripers generally spawn for the first time somewhere between 32 and 34 inches in size. There is an additon factor in the assessment which is called "spawning Stock biomass." That's the amount of spawning fish and the FMP will cintain targets for the level of SSB, that will generall translate into size limits. All of this is a gross oversimplification, but it should be enough to gett he conversation started.