Pond - Black Swann events are very difficult to anticipate and or plan for by definition . Buffering space is one concept that helps. If you have room in your pond for all factors you are way ahead. By buffering space I mean - Something that lessens or absorbs the shock of an impact or one that protects by intercepting or moderating adverse pressures or influences.
Absent an unknown water quality issue I have from the outset thought Tracy's event was a carrying capacity issue.
Quantifying things is doable even if it is estimated based on tools we understand like RW , RC , water quality measures , plankton densities , seine surveys , electrofishing, etc. . The most important concept to keep in mind is that we are always working behind the curve. That is, those tools give us a point of reference in time that will change rapidly in advance of our management actions (delayed effect). The real gift , the "art" part of fisheries management - is the ability to foresee/anticipate future results from current info and management actions and be able to adjust to changing (unanticipated) conditions , often in mid-stream.
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