That reminds me of the discussions about overfishing. The amount of fish in the sea is a mere few percentages of what it was a century ago, but that already was

That reminds me of the discussions about overfishing. The amount of fish in the sea is a mere few percentages of what it was a century ago, but that already was way, way less than it was in the centuries before that. And we only went to fish in the sea after we had exhausted the rivers. This is the shifting baseline effect and it really negatively affects conservation efforts.