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Fisheries - General

Like most fisheries around the world, Canada's are in steep decline. As a well-documented example, the east coast cod fishery has collapsed and recovery is proceeding at an extremely slow pace.

However, in the past 10 years, there have been tremendous advances in the scientific understanding of environmental and fisheries history. This new knowledge has provided a much more complete picture of the biological potential and the workings of the marine food chain.

New research findings paint a much more complete picture of the marine world as it existed before Europeans began commercial operations.  They establish that the biomass of our major food species is close to 95% lower than it was when Jacques Cartier first sailed into the Gulf of St. Lawrence.

In 1508, cod were far more numerous and far larger than today. In fact, there are so few cod surviving now, part of the problem of trying to renew the stocks is that the low numbers result in too low a sperm density in the water to effect sufficient fertility of the eggs during spawning.

Advanced fisheries research will allow us to determine what level of harvesting represents a sustainable catch for which species. Despite being a source of vital nutrients, the oceans will not provide more than 1% of the dietary calories our current human requires.

In 2016, Canada has adopted a much more science-based fisheries policy aimed at sustaining and rebuilding the stocks from their very low levels.   Attaining the health of fisheries in the past though will be difficult with intense pressure for food production as well as the impacts of climate change.

But at least as far as the cod fishery is concerned, we have stopped trying to maximize exploitation and have started to restrict catches to levels which are sustainable in the long term.

Like most fisheries around the world, Canada=s are in steep decline. As a well-documented example, the east coast cod fishery has collapsed and recovery is proceeding at an extremely slow pace.

However, in the past 10 years there have been tremendous advances in the scientific understanding of environmental and fisheries history. This new knowledge has provided a much more complete picture of the biological potential and the workings of the marine food chain.

New research findings paint a much more complete picture of the marine world as it existed before Europeans began commercial operations.  They establish that the biomass of our major food species is close to 95% lower than it was when Jacques Cartier first sailed into the Gulf of St. Lawrence.

In 1508, cod were far more numerous and far larger than today. In fact, there are so few cod surviving now, part of the problem of trying to renew the stocks is that the low numbers result in too low a sperm density in the water to effect sufficient fertility of the eggs during spawning.

Advanced fisheries research will allow us to determine what level of harvesting represents a sustainable catch for which species. Despite being a source of vital nutrients, the oceans will not provide more than 1% of the dietary calories our current human requires.

In 2016, Canada has adopted a much more science based fisheries policy aimed at sustaining and rebuilding the stocks from their very low levels.   Attaining the health of fisheries in the past though will be difficult with intense pressure for food production as well as the impacts of climate change.

But at least as far as the cod fishery is concerned, we have stopped trying to maximize exploitation and have started to restrict catches to levels which are sustainable in the long term.

Fisheries - Advanced

The history of the North Atlantic cod stocks is one of over-exploitation and very slow recovery. In fact, the cod have collapsed twice in the past 150 years with the first event starting in the early 1800s due to warming/ocean current changes added to increasing exploitation. This crash bottomed out in the late 1800s with the highest point of recovery coming in the late 1940s. Almost full recovery did occur though, (albeit after 60 years), but the collapse was only down to 40% of the natural stock level. 40% represented a still substantial and fairly healthy population of cod which not only grew back to near former levels but was also able to sustain significant landings

The fisheries collapse is a classic resource crash because fish were the reason the Portuguese first came to the New World. It is probable they were on the Grand Banks (and therefore Newfoundland) by the mid-1400s, well ahead of Columbus.

But after WWII, fishing activity intensified and human pressure drove the cod into decline. Peak landings occurred in 1968 at 3 times the 100 year average. By the early 1990s, stock biomass had collapsed to 3% of natural levels and large scale fishing was ordered suspended as over-fishing had pushed the cod to critically low levels.

In 2010 stocks had recovered to only 8% of their natural level and landings were only 5% of their 100 year average. This has inflicted a huge economic and social loss on fishing communities and provides a vivid lesson in how not to manage a renewable resource. Recovery takes far longer than exploitation and in many cases of environmental degradation, full recovery never happens.

Blame for the cod catastrophe can be shared by everyone but, in this case, foreign fleets accounted for 80% of the harvest and were completely unregulated. The reason industrial fleets from Spain, Portugal and the Iron Curtain Baltic countries travelled great distances to the Grand Banks was their own fisheries had been greatly diminished by over-exploitation. They were merely moving on the next greenest field.

The cod in Iceland’s waters had also come under severe pressure during the same period but Iceland’s Fisheries Ministry reacted more quickly on the recommendations of their scientific experts. Even then, scientists from the Hafrannsoknastofnunin (Marine Research Institute) were under considerable pressure from commercial interests to allow higher levels of harvest. The combined motivations of greed and immediate need are present in all resource management conflicts. Usually the motivation of desperation wins out over long term planning and the interests of following generations.

Canada’s cod experience is being mirrored all over the world with many fisheries under extreme stress. Many humans are desperate for the income and food provided by the sea and many have no other options. In addition, climate change is altering water temperature and currents so that feeding and breeding grounds patterns are changing. Acidification of the oceans is another source of pressure for many food stocks.

Fisheries science is now far ahead of even what it was 20 years ago and our understanding of what a natural marine eco-system looks like is radically different from that which we envisioned 50 years ago. Most governments and international organizations are paying increasing attention to their scientific advisors and setting regulations accordingly. However, there is a great deal of unregulated fishing and ocean stocks continue to decline.

Pressure on marine life is as great as ever and recovery remains an open question in a world of expanding human numbers and changing environment.

Fisheries - Reference

Subject MatterSource

Abundance estimates of wild and hatchery Pacific salmon Oncorhynchus spp. are important for evaluation of stock status and density-dependent interactions at sea.bundance estimates of wild and hatchery Pacific salmon Oncorhynchus spp. are important for evaluation of stock status and density-dependent interactions at sea.bundance estimates of wild and hatchery Pacific salmon Oncorhynchus spp. are important for evaluation of stock status and density-dependent interactions at sea.bundance estimates of wild and hatchery Pacific salmon Oncorhynchus spp. are important for evaluation of stock status and density-dependent interactions at sea.bundance estimates of wild and hatchery Pacific salmon Oncorhynchus spp. are important for evaluation of stock status and density-dependent interactions at sea.
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Taylor & Francis Online

Managing the remnants of the ocean’s resources is a critical issue worldwide, but evidence for what constitutes a healthy fish population remains controversial.
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Andrew A Rosenberg

With marine ecosystems endangered by a warming climate and exploding human population growth, a critical transformation is taking place in the way the world
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Harvard University Press

Fisheries Study Listing

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Myers Lab

Listing of Fisheries Studies
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Dr Ransom A. Meyers

Fisheries Lab - Heike Lotze
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The Lotze Lab

Remembering the mighty cod fishery 20 years after moratorium

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CBC

Across 256 reviewed records, exploited populations declined 89% from historical abundance levels (range: 11–100%).

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Heike Lotze

Archaeological records highlight the abundance and diversity of marine species used by indigenous people over the last 2000–3000 years. Europeans colonized the area in the late 1700s and rapidly transformed the environment

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Heike Lotze

Sockeye salmon adult populations in widespread decline

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CBC

The population breakdown in the world's oceans is changing dramatically, with big fish numbers dropping while smaller fish become more plentiful

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UBC

–Abundance estimates of wild and hatchery Pacific salmon Oncorhynchus spp. are important for evaluation of stock status and density-dependent interactions at sea. We assembled available salmon catch and spawning abundance data for both Asia and North America and reconstructed total abundances of pink salmon O. gorbuscha, chum salmon O. keta, and sockeye salmon O. nerka during 1952–2005
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Gregory T. Ruggerone

Our research focuses on human-induced changes in marine populations, communities and ecosystems. This includes past, present and potential future human impacts in the ocean such as exploitation, habitat alteration, nutrient pollution, and climate change.

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Heike Lotze Labs

Managing the remnants of the ocean’s resources is a critical issue worldwide, but evidence for what constitutes a healthy fish population remains controversial.
Download PDF Doc
Ransom A. Myers
Motion Graph: Fisheries Motion Graph
Impact Index

Fisheries

Foreign Fleets Impact

80%
Cause of the Crash of the North Atlantic Cod in the 1970s
  • Foreign Fleets 80%
  • Domestic Overfishing 20%

Foreign industrial fishing fleets were responsible for most of the rapid  increase in catch which led to the collapse of the cod fishery.  If left on its own, the Canadian domestic fishing industry would have taken longer to destroy the resource.

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