Shifting baselines is a term we often refer to when looking at a fishery. Essentially, it means that each generation has a different starting baseline than others, as each generation appears that starting baseline will be smaller than it started off as humans are consuming more and more. This applies to Atlantic Cod as each generation that went on fishing for Cod thought they did have decent fishing, but had no clue of the actual historical numbers.
We can avoid falling into shifting baselines by making sure to look at the entire big picture, to take in account the sustainability of that fishery from the start of people harvesting from it.
The connection made between the fall of the cod and shifting baselines is what I said, I agree on the fact that fishers thought that this was normal for the fishing population because this is what they’ve grown up with.