The variability of fisheries and fish populations prior to industrialized fishing: An appraisal of the historical evidence

This paper assesses the potentials of the available time series (50 years+) from historical records of the pre-industrial period until c. 1850–1950. A number of historical records from commercially important fish species are available for examining natural variability of fish stocks. Especially for North Atlantic and Japanese fisheries historical data have been retrieved from archives and museums, which cover time spans of 50–350 years. This makes it possible to examine natural variability of fish stocks over a much longer time span than what is normally possible with modern survey data and commercial catch data. Furthermore, historical evidence from the pre-industrialized period have the benefit of stemming from a period in time, when fishing had an insignificant impact on the abundance of open sea fish stocks. The best material comes from cod and herring fisheries, where it is possible to reconstruct CPUE as accurate as catch per boat per day absent, as well as changing spatial distribution over longer time periods.