How to measure a fish stock

How fisheries scientists use models to measure fish stocks using Virtual Population Analysis (VPA) and why it is important for fishermen to report all catches and discards so that the fisheries models provide for better fishing opportunities.

[@ashieduafoteyjoshua1729]

Impressive

[@eyawaaaronmiles.p1532]

Sample problem pls?

[@Magnus247]

Try this one ruclips.net/video/tDK8sFkwJkg/видео.html (data taken from the book Marine Fisheries Ecology by Jennings et al)