Our comprehensive review of 25 North Atlantic fisheries shows that extractions during the early modern period, c. 1520-1790, vastly exceeded previous assumptions. North Atlantic fisheries for cod and herring were of an order of magnitude comparable to industrial fisheries for several centuries before the Industrial Revolution took off. This is a finding that challenges notions of relatively unimpacted marine ecosystems before the Industrial Age.
We identify two periods of accelerated marine extractions (1540-1620 and 1750-1790) when the growth rate of fish landings was higher than human demographic growth. These periods point to the role of fish supplies for the expansion of early-modern societies.
We have charted changing fish consumption preferences over the course of the early modern period.The most important human benefit of elevated marine exploitation was increased food security. Annual consumption of herring and cod almost doubled during the Fish Revolution of the sixteenth century from 2.9 to 5.7 kg per capita by 1790; total seafood consumption averaged 10 kg by 1790 with significant regional differences. The amount may be compared with the global average fish consumption of 10 kg in 1960, which includes other species as well. Access to cheap dried protein will have been critical to food security in pre-industrial societies.
There was a geographical shift in the focus of fisheries from east to west. Herring was increasingly sourced in the North Sea rather than the Baltic, and cod was caught in the Northwest Atlantic rather than the Northeast. The reorientation of geography was of geopolitical significance. Regional studies bring out the specificities of change in the Irish and Celtic Seas, the Danish North Sea fisheries, the Baltic, and North Atlantic islands.
Conditioned by market forces, the ‘fish revolution’ of the 1500s reshaped alignments in economic power, demography, and politics. With acute consequences in peripheral Atlantic settlements from Newfoundland to Scandinavia, it held strategic importance to all the major western European powers.
War and peace had an inverse effect on marine life. Wars brought a moratorium on fisheries that enabled fish populations to rebuild. In view of the scale of cod extractions in the 1780s, we conclude that the Napoleonic Wars brought a similar respite to Newfoundland cod to that of the “Great Fishing Experiments” of World War I and II.
Warfare and conflicts over access to fishing grounds constituted the main constraint on the herring and cod fisheries. The general downturn of landings after the 1620s, lasting into the eighteenth century, was broadly mirrored by a century of European warfare that was only effectively ended by the Treaties of Utrecht (1713-1714). While the conflicts drove up prices of fish and thus encouraged some fishers to go to the sea, the vagaries of the war caused fishing fleets to be destroyed or pillaged. Peace on the other hand was clearly associated with a steady rise in fishing effort. The relative peace of the sixteenth and eighteenth centuries provided European fishers with the opportunity to build and develop the extensive fisheries that constituted the second and third periods of elevated marine extractions.
Climate change (the downturn of North Atlantic temperatures in the second half of the seventeenth century and increased storminess) is likely to have reduced fishing effort, while changes in marine productivity, primarily zooplankton, may have impacted stock abundance. While the volatility of Northwest cod landings is probably best understood in a geopolitical context, the decadal volatility of North Sea herring landings indicates stock fluctuations that may be related to predator/prey relationship and volcanic eruptions driving marine productivity. There were distinct shifts in the balance of fish production between the Northeast and the Northwest Atlantic. Biophysical changes may potentially explain this see-saw phenomenon.
Scholarly implications
NorFish has significant methodological implications for marine environmental history. The project took a multi-disciplinary, humanities-led approach and established a robust quantitative framework of extractions, supplies and prices, while also charting the qualitative preferences and politics that motivated actors of the fish revolution across the North Atlantic. We have published on digital environmental history methodology in the course of the project.
Societal importance
The scale of pre-modern cod and herring fisheries underline the conclusion of Pinnegar & Engelhard (2008) that “ecosystems were not pristine before the onset of industrial fishing and it is difficult to assess the ‘virgin’ state of a population given that it may have been subject to moderate or even high levels of fishing mortality for many centuries.” Our findings provide essential information for our understanding of human impact on Life Below Water (United Nations Sustainable Development Goal 14) (UNDP).
Our finding that increased availability of fish likely played a significant role in the demographic rise of Western Europe (Maddison Project Database, 2020) is of relevance to the United Nations Sustainable Development Goal 2 (Zero Hunger) (UNDP).
We have discussed the broader implications of our findings in P. Holm, SDG 14 Life below Water. Exploiting and Managing an Alien and Unseen World. Martin Gutman & Daniel Gorman (eds), , Oxford University Press (expected publication data: Feb 2022) [F2]
