A group of American scientists were asked to evaluate the effect of catch shares (another name for ITQs - individual tradable quotas) in those fisheries
where catch shares had been applied. They found some benefits, but their main finding, IMO, was that the catch shares have had no effect on fish biomass. This means that the number one claim of catch shares promoters that they represent a tool for fish stocks conservation/sustainability, etc., doesn't hold water. Characteristically, and unfortunately, the social persecussions of the quota system were totally absent from the analysis.
BTW, I posted today the abstract and reference to this report on the FISHFOLK discussion list, as well as link to the whole article. For those interested, but without access to FISHFOLK, ask me for the link at benyami@actcom.net.il, or through the my Facebook page. MB-Y 
