Atlantic Fisheries Adjustment Program

Northern Cod Science Program

For centuries the natural growth of the northern cod stock could easily replace as much fish as the ice and weather would allow us to catch -- and that was a lot. The cod stock in the fisheries management area known as 2J3KL historically supported landings of about 250,000 tons a year, or about 75% of the cod landed in Newfoundland and Labrador. With the stock in no jeopardy, we could trust nature to look after herself.


In the last generation, however, the intensity of fishing and the efficiency of fishing technology have made it possible to deplete this stock. It has become critical to understand the life cycle, behaviour and environment of these fish. Through the Northern Cod Science Program (NCSP), the Atlantic Fisheries Adjustment Program (AFAP) gives fisheries scientists in the Newfoundland region $40 million over five years to learn a great deal more.

Following are objectives and highlights of the work:


One of the most difficult but critical tasks in fisheries science is estimating the abundance of different stocks of fish. In the case of northern cod, new funds allow more intensive efforts to improve the range and quality of data on which these annual "stock assessments" are based.

The Department of Fisheries and Oceans (DFO) is adding extra sea days to its fall groundfish surveys, to get more precise evidence of how much cod is out there.

An echo-sounding technique called hydroacoustics may offer another way to estimate cod abundance. This system works best when cod are densely gathered on the spawning grounds, but that can mean operating in heavy ice. After several seasons of refining techniques, scientists have begun to get results, but they will need years of similar success before this technique can provide an independent measure of cod abundance.

Efforts will be expanded to work with inshore fishermen on ways to incorporate their experience into the highly technical process of stock assessment. Scientists will analyze the inshore catch/effort data collected by Statistics Branch, and collaborate with inshore fishermen in studying what kinds of ocean conditions affect cod trap landings.

Funds from NCSP have made it possible to process a huge backlog of catch data gathered by fisheries observers on the Canadian and foreign trawler fleets. Getting this data into a "machine readable" form will make it much more accessible to the biologists who estimate fish populations.


Some of the most elementary details about the life history and habits of cod are still poorly understood. To wisely manage this resource, we need to learn a great deal more about it.

Scientists are using high resolution sounders to track large schools of cod as they move to inshore waters in early summer. Results so far have been spectacular. This approach promises important new insights into the migratory routes cod choose, the timing and nature of their migration, and how they respond to oceanographic conditions and the presence or absence of food.

Researchers want to know what cod eat when capelin are scarce, and what role capelin play in the annual inshore migration. The best clues are in the contents of cod stomachs, but stomach analysis is painstaking and costly work. NCSP funds have made it possible to complete the analysis of a large backlog of cod stomachs collected on survey cruises.

Teams of biologists and oceanographers are studying how cod eggs and larvae drift with ocean currents, whether the large bays of the northeast coast serve as important "nurseries" for juvenile cod, and what determines how many young cod survive.

An intensified tagging program will help to clarify the relationship between sub-stocks of cod which use different offshore spawning areas and which migrate both along the banks and across the banks to inshore feeding grounds.

A DFO biologist is studying whether trawling affects the spawning behaviour of cod or the viability of eggs laid while trawlers are present in the spawning area.


For all their importance to us, cod are just one strand in a complex web of relationships in the ocean. To know more about them, we must understand their role in the ocean ecosystem, and we must know more about the ocean itself.

Studies have begun to look at the impact of trawls on sea bottom life, in an effort to learn whether trawling significantly affects ocean ecology.

Oceanographers are studying seasonal changes in the water on the Labrador/Northeast Newfoundland Shelf, and collaborating with biologists who will look at how these ocean conditions affect cod behaviour. They want to know how changes in underwater weather affect where cod move, how many young cod live to maturity and how many are available to the fishery.

The Northern Cod Science Program is funding intensified research into harp and hooded seals. Studies are trying to establish: how many seals there are; what kinds of prey they prefer; how much food they require at various seasons; and whether their movements bring them into extensive contact with cod and important prey species like capelin.

DFO scientists are exploring the potential of a somewhat radical theory that the biomass, or total weight, of each portion of the ocean food chain is roughly equal to each other part, so that one can serve as a measure of the others.

Government toxicologists are looking for traces of heavy metals, dioxins and furans in fish, in response to concerns that pollution may contribute to declining ocean productivity. They want to establish the levels of any contaminants present, then move on to laboratory studies of possible effects.


Funds from the Northern Cod Science Program are helping DFO exploit the promise of new technology, using new micro-electronic instruments as our eyes and ears underwater. Computers and related equipment not only gather information never before available, but allow us to process and apply it promptly.

DFO will fund research in the application of remote sensing techniques -- like satellite imagery -- to fisheries research.

Other uses of remote sensing include "tagging" seals and fish with instruments which report their position and record environmental details like water depth, temperature and salinity.

DFO is hiring a fishing gear technologist to improve the performance of research trawls and to standardize survey procedures. Today, underwater cameras and acoustic systems allow us to monitor fishing gear performance, both to improve the consistency of tows and to alert us to problems as they happen.


Effectiveness in fisheries science demands extensive personal contact -- with other scientists, chiefly, but also with members of the public who fund the research and with fishermen and industry representatives whose livelihood depends upon it.

DFO is collaborating with scientists in universities and in other countries, to share data, methods and insights in fisheries science and oceanography. Scientific ties with Iceland and Norway are especially close, because of the importance of cod, capelin and marine mammals in their waters as well.

DFO is putting a high priority on communications, to enhance public understanding of science issues and both the strengths and limitations of the scientific process as it relates to northern cod.


The flip-side of trouble is opportunity. The turmoil which followed cuts in northern cod quotas provides the impetus for a major new effort to learn more about this crucial resource. A new emphasis on ecology and on understanding the entire ocean environment ensures that the knowledge gained in this effort will have broad application in Canada's maritime industries.

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