SPEAKER: Dr. Ray Hilborn, University of Washington
DATE: Monday, March 11
LOCATION: MBL's Lillie Auditorium
Lessons from the RAM Legacy data base, stock status, regime shifts and dynamics
at low densities.
ABSTRACT: This talk will summarize recent analysis from the RAM Legacy data base on the trends in abundance, catch and recruitment for stocks constituting 40% of the worlds catch. These stocks represent most of the industrial fisheries of the developed world and the high seas, but developing countries are poorly represented. Stock status is highly variable by region, but at current exploitation rates most stocks are expected to rebuild to be at or greater than BMSY and only a small fraction of stocks are now exploited so hard that they are expected to remain overfished by US definitions. Analysis of trends in total production and recruitment indicate that a majority of stocks show periodic shifts in productivity unrelated to abundance. Analysis of the productivity at low densities provides no suggestion of depensatory processes and low abundance stocks, when fishing pressure is reduced, do increase in abundance.