Baselines, as per one of ICES strategic initiatives, are historical data representing ecosystem conditions before a certain point of human disturbance.
Another key point on the historical baselines issue. Science talks about a desired ecosystem state, but definitions have to be come up with first. How pristine is pristine? And where's the historical cut off point; what point in history is the best?
Communication and cooperartion between social and natural scientists as well as between science and industry - in fact cooperation in general - was one of the hot topics of the day.
This funny example had a serious undertone. If there are two correlated effects - as per Nick Cage films and number of people drowning in pools - then disentangling them when they both impact upon a certain thing is tough. So if warming temperatures and fishing pressure, for example, run side-by-side in their impacts on the ecosystem, then accurately distinguishing them is a real challenge.