Collapse of the Atlantic northwest cod fishery
The northwest Atlantic fishery abruptly collapsed in 1992, following overfishing since the late 1950s, and an earlier partial collapse in the 1970s.
In 1992 the Canadian government declared a moratorium on the Northern Cod fishery, which for the past 500 years had largely shaped the lives and communities of Canada’s eastern coast. The interplay between fishing societies and the resources which they depend on is obvious to almost any observer: fisheries transform the ecosystem, which pushes the fishery and society to adapt. In 1992 summer, when the Northern Cod biomass fell to 1% of its earlier level, Canada’s federal government saw that this relationship had been pushed to breaking point, and they declared a moratorium, ending the region’s 500-year run with the Northern Cod.
The collapse of the Northern Cod fishery marked a profound change in the ecological, economic and socio-cultural structure of Atlantic Canada. The change was expressed most acutely in Newfoundland, whose continental shelf lay under the region most heavily fished, and whose communities were nearly all of those who lost employment because of the moratorium. Considering the importance of the cod fishery to the livelihood of Canada’s coastal communities, and the Northern Cod’s initial abundance in the region, the fishery being mismanaged until it collapsed – from which to this day it has not recovered – is nothing short of shocking.
In an attempt to make sense of a blunder of such large proportion, academics have highlighted these three contributing factors in the eventual collapse of the cod fishery:
A major factor that contributed to the depletion of the cod stocks off the shores of Newfoundland included the introduction and proliferation of equipment and technology that increased the volume of landed fish. For centuries local fishermen used technology that limited the volume of their catch, the area they fished, and let them target specific species and ages of fish. From the 1950s onwards, as was common in all industries at the time, new technology was introduced that allowed fishermen to trawl a larger area, fish to a deeper depth and for a longer time. By the 1960s, powerful trawlers equipped with radar, electronic navigation systems and sonar allowed crews to pursue fish with unparalleled success, and Canadian catches peaked in the late 1970s and early 1980s.
These new technologies adversely affected the Northern Cod population in two important ways: by increasing the area and depth that was fished, the cod were being depleted until the surviving fish could not replenish the stock lost each year; and secondly, the trawlers caught enormous amounts of non-commercial fish, which were economically unimportant but very important ecologically: incidental catch undermines the whole ecosystem, depleting stocks of important predator and prey species. With the Northern Cod, significant amounts of capelin – an important prey species for the cod – were caught as bycatch, further undermining the survival of the remaining cod stock.
Another factor important to consider in understanding the fishery’s collapse is uncertainty in assessing the cod as a resource. Management of a resource is an extremely complex task, with a multitude of interests, perspectives, and sources of information to take into account; when knowledge regarding the resource is limited, or clouded by imprecision, the task of managing it becomes even more difficult. The management of fisheries is associated with an especially high degree of uncertainty due to problems inherent in the nature of the resource. Newfoundland’s cod fisheries were no exception: an imperfect understanding of the ocean ecosystem; technical and environmental challenges associated with observation techniques, which led to incomplete data on the resource (the cod); and the naturally high levels of variability in the population due to dynamic environmental factors (such as ocean temperature) combined to make it arduous to discern the effects of exploitation. Unfortunately, this led to predictions about the cod stock that were mired in uncertainty, making it more difficult for the government to choose the appropriate course of action.
In addition to ecological considerations, decisions regarding the future of the fisheries were also influenced by social and economic factors. Throughout Atlantic Canada, however most pronounced in Newfoundland, the cod fishery was a source of social and cultural identity. For many families, it also represented their livelihood: most families were connected either directly or indirectly with the fishery as fishers, fish plant workers, fish sellers, fish transporters, or as employees in related businesses. Additionally, many companies, both foreign and domestic, as well as individuals, had invested heavily in the boats, equipment and the infrastructure of the fishery, and therefore felt it was in their best interest to maintain an open-access policy to the ocean and its resources. What this alludes to is the unfortunate paradox that often accompanies open-access resources and is known by most as the Tragedy of the Commons: what is in the individual's best interest is not always in the best interest of a society at whole. In the case of Newfoundland and the Northern Cod fishery this meant that from the perspective of the individual participating in the fishing industry, maximizing their catch was in their best interest; however when the government failed to intervene – due largely to the highly sensitive nature of the political discourse created by the expansive group of stakeholders – the ecosystem was brought past its threshold and collapsed, leaving everyone worse-off.
When the government finally acted, it was too late. The 1992 moratorium was at first meant to last two years, hoping that the Northern Cod population would recover, and along with it the fishery. Unfortunately, the damage done to Newfoundland’s coastal ecosystem was indelible, and even after sixteen years, the Northern Cod population has not rebounded and the Cod Fishery remains closed.
Impact of the collapse on Newfoundland
The moratorium in 1992 marked the largest industrial closure in Canadian history. In Newfoundland over 35,000 fishers and plant workers from over 400 coastal communities became unemployed. In response to dire warnings of social and economic consequences, the federal government intervened, initially providing income assistance through the Northern Cod Adjustment and Recovery Program, and later through the Atlantic Groundfish Strategy, which included money specifically for the retraining of those workers displaced by the closing of the fishery. Newfoundland has since experienced a dramatic environmental, industrial, economic, and social restructuring, including considerable outmigration, but also increased economic diversification, an increased emphasis on education, and the emergence of a thriving invertebrates fishing industry (as the predatory groundfish population declined, snow crab and northern shrimp proliferated, providing the basis for a new industry that is roughly equivalent in economic value as the cod fishery it replaced).
Present recovery status
In November of 2006, Fisheries and Oceans Canada released an article suggesting that the unexpectedly slow recovery of the cod stock is due to inadequate food supplies, cooling of the North Atlantic, and a poor genetic stock due to the overfishing of larger cod. During the summer of 2011, a study was announced to show that recovery of East Coast cod stocks around Nova Scotia showed promises of recovery, despite earlier thoughts of complete collapse. It was found that initial stages of recovery began around 2005, though more time and studies were needed to study the long-term stability of the stock increase. In addition in 2010 a study by the Northwest Atlantic Fisheries Organization found that stocks in Grand Banks near Newfoundland & Labrador had recovered by 69% since 2007, though that number only equates to 10% of the original stock.
Changing Ocean Temperatures, Circulation Patterns Affecting Young Atlantic Cod Food Supply
Changing ocean water temperatures and circulation patterns have profoundly affected key Northeast U.S. Continental Shelf zooplankton species in recent decades, and may be influencing the recovery of Atlantic cod and other fish stocks in the region.
NOAA researcher Kevin Friedland and colleagues looked at the distribution and abundance of important zooplankton species, sea surface water temperatures, and cod abundance. They found that zooplankton species critical for the survival of Atlantic cod larvae have declined in abundance in the same areas where Atlantic cod stocks have struggled to rebuild after an extended period of overfishing.
"Temperature is a governing factor in the growth, reproduction and distribution of marine organisms. Shifting temperature distributions, whether triggered by natural or human factors, can cause the redistribution of plankton communities on regional and basin-wide scales," said Friedland, lead author on the study and a scientist at NOAA's Northeast Fisheries Science Center (NEFSC).
The change in thermal habitats has had biological consequences on multiple levels in the food chain, according to the study in press in the journal Progress in Oceanography.
"The geographic and depth distributions of fish and shellfish populations can also change based on their preferred thermal habitats. Future changes in thermal conditions are expected to lead to further shifts in the distributional ranges of species by, in many cases, the loss and gain of local populations," said Friedland.
Friedland and his colleagues found that ocean water temperatures of the Northeast Continental Shelf have increased in recent decades, but these changes have not been uniform over the entire ecosystem. Warm water habitats (16 to 27 C, 60 to 80 F) have increased and cool water habitats (5 to 15 C, 41 to 59 F), historically the core habitats in the ecosystem, have declined; however, the coldest habitats in the ecosystem (1-4 C, 34-39 F) have either stayed the same or increased slightly during the study period 1982-2011. This discontinuity is attributed to changes in circulation in the northern Gulf of Maine associated with the Labrador Current.
Atlantic cod off the Northeast U.S. are managed as two stock units, the more northerly in the Gulf of Maine and the more southerly on and around Georges Bank. There are upward of ten known spawning populations within these two stocks, and the very young fish that they produce are found in specific larval development areas. Two zooplankton species that serve as food for Atlantic cod (Gadus morhua) larvae are Pseudocalanus spp, and Centropages typicus. The former is associated with winter-spawning cod, and the latter with spring-spawning cod.
The researchers developed indices of zooplankton and cod abundance in six index areas, relating larval feeding and development areas to associated areas where adults reside. They found that Pseudocalanus spp has declined in abundance on parts of Georges Bank and in the eastern Gulf of Maine, areas where cod have been less abundant in recent years. Centropages typicus declined in abundance in the eastern Gulf of Maine as well. The areas where these zooplankton species have declined are spatially discrete and are related to the change in core thermal habitat of the ecosystem.
The abundance of zooplankton species is measured by the NEFSC's Ecosystem Monitoring Program (EcoMon), which conducts shelf-wide bimonthly surveys of the ecosystem. Data and observations from the NEFSC's spring bottom trawl surveys were also analyzed.
Although the researchers concentrated on Atlantic cod recruitment success and population trends, many of the zooplankton species examined are important as prey for early life stages of other fish species and marine mammals. These zooplankton species are important within the Northeast Shelf ecosystem, and can serve as model organisms to test the effect of thermal habitat on changes within the food web.
An Ecosystem Advisory issued by the NEFSC on April 25, 2013 provides additional information related to the Northeast Shelf ecosystem, notably a description of the extreme warming that occurred on the Shelf during 2012 and the associated shifts in thermal habitat.