I'm not sure if anyone has ever posted this study, but if you want to know the effects of oyster harvesting on our ecosystem, wade through this study. The conclusions of the study may not help us, but if you look at the differences between the south end of the lake compared to the north, it is easy to see how over harvesting will impact recreational fishermen.
http://etd.lsu.edu/docs/available/etd-12122011-105427/unrestricted/BeckThesis.pdf