Monster Seminar JAM - A Phase Shift in Community Composition in an Intertidal Assemblage: Stable? An Alternative State? Is there Hysteresis in its Future?
Dr. Bob T. Paine, Dept. of Biology, University of Washington.
Dramatic changes in an assemblage's organization and the associated, implied shifts in species composition must present managers with potential nightmares. Developing appreciation that such shifts can both be experimentally produced and forced naturally has accelerated interest in the topic. The 1997-98 ENSO apparently initiated such a change in the mid-low intertidal zone on Tatoosh Island, my primary study site since 1968. Long term data sets establish the reality of the shift. I will describe samplings and experiments which quantify the shift, clarify whether and why the new state is "stable", and provide insights into the phenomenon of hysteresis
Date and Time:
December 18, 2003,
11:00 am - 12:30 pm