One of the graphs from Rutger's study which illustrates the relationship of length and sex for summer flounder. Graph is in centimeters, 18 inches equals 45.72 centimeters. You can see how disproportionate the relationship is between males and females as size increases to the point where almost all fish over 19.5 inches are females. NMFS's insistence on increasing size to control catch relative to this data is one of the reasons recruitment has been decimated. Combine that with the following statistics and the results are disastrous.

Reproduction:
Both males and females become sexually mature at the age of 3. The fecundity (number of eggs produced in a single spawning season) of females increases with size and weight. A 14 inch female produces about 460,000, and a 27 inch female about 4,200,000 eggs in a season. Reproduction takes place in the fall, as soon as the fish begin migrating to wintering grounds. Peak spawning activity occurs from early September through early November in water temperatures of 53 to 66 degrees F and at depths of 60 to 160 feet. The center of spawning activity occurs off the coasts of New York and New Jersey with less concentrated activity occurring in southern New England waters. The eggs float in the water column, hatching 72 to 75 hours after being laid.

Translated, not only are we harvesting almost exclusively breeders, every time size limits are increased we're increasing the harvest of larger females with considerably greater egg production capacity at what could conceivably be a 10:1 ratio. Couple that with the commercial fleet harvesting concentrated schools of migrating fish during their fall / winter offshore migration and spawn and NMFS / ASMFC wonders why the biomass is trending down over the last 15 years. You can draw your own conclusions but the data strongly supports a gender imbalance created in the biomass by size increase legislation over the last almost twenty years compounded by commercial harvest in the fall / winter months during the spawn without understanding the negative impacts that harvest has on overall egg reproduction. It's obvious for every female harvested we lose the immediate benefit of that years egg production. Larger question in my opinion is how many eggs already released are destroyed by continued netting and what impact does the harvest have on stressing out the biomass, potentially impeding it's ability to reproduce. No one to my knowledge has that answer and it arguably might be one of the most important pieces of the puzzle.

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