Sea Ice, Climate, and Icelandic Fisheries in the Eighteenth and Nineteenth Centuries

The expansion and subsequent decline in catches in many fisheries of the world during the 20th century suggest that the history of fisheries needs our urgent attention. Analysis of environmental effects on fisheries in the past (when overfishing was not an issue) may cast light on current concerns about declining fish stocks. Primary documentary evidence from Iceland was used for preliminary investigations into correlations between sea-ice extent, sea temperatures, ocean currents, and cod fishing, and hence between severe weather and the decline of Icelandic fisheries in the past. The sources suggest that fishing was generally successful in Iceland during the medieval period and well into the 16th century. However, in the 17th through the 19th centuries, the fisheries failed on numerous occasions, sometimes for several years. The causes of these failures were complex. Climate likely played a part, and this was certainly the perception of contemporary writers; however, socioeconomic factors were also involved.