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

摘要

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 fishspecies are available for examining natural variability of fish stocks. Especially for North Atlantic andJapanese fisheries historical data have been retrieved from archives and museums, which cover time spans of50-350 years. This makes it possible to examine natural variability of fish stocks over a much longer timespan 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 comesfrom cod and herring fisheries, where it is possible to reconstruct CPUE as accurate as catch per boat per dayabsent, as well as changing spatial distribution over longer time periods.