The split over whether catch is a useful indicator of fish abundance (D. Pauly, R. Hilborn and T. A. Branch Nature 494, 303–306; 2013) is a false dichotomy. Not because a realistic position lies somewhere in between, but because the focus is too narrow.

In the whole-ecosystem approach to fisheries management, data on all species, including by-catch species, must be considered. A broad range of information is therefore used to assess the health of fisheries worldwide, from no-data situations that rely on precautionary and risk-based approaches, to data-poor fisheries in which catch data are unreliable, as well as data-rich fisheries that are well supported by catch data and fishery-independent surveys.

As climate change alters the distribution and abundance of different species, catch data may become less useful and new methods will be needed for assessing fish stocks. However, even the best estimates of fish numbers will not improve fisheries' health without good leadership, robust social capital, and effective conservation and stock-rebuilding policies.