Thank you, Trevor.
I'd also like to thank the honourable committee members for this opportunity to speak with you today about the status of northern cod and the science that we do on this important resource. I trust that all of you have a copy of the presentation, so I'll go through it fairly slowly, with not too much detail. It shouldn't take more than about ten minutes.
I'd like to begin by clearly defining what we mean by northern cod. There are in fact five managed stocks of cod off Newfoundland and Labrador, and northern cod occupies the area outlined in red on the map. It doesn't include the south and west coasts of Newfoundland or the southern Grand Banks. Northern cod occupies a huge stock area, and as we know, it once supported an enormous fishery. We harvested over 800,000 tonnes of cod in the 1960s in a single year. The average harvest was about 240,000 tonnes in the 1980s, and as we know, the stock collapsed and a moratorium was imposed in 1992. Small-scale inshore fisheries have operated since then intermittently, typically with landings between 4,000 and about 8,000 tonnes per year.
DFO has adopted what we call a precautionary approach framework as part of its policy for managing fisheries resources. Three zones are defined for each fish stock—critical, cautious, and healthy, depending on the resource status. Science provides advice on where the boundaries of these are and the current and past status relative to these boundaries. We use the long history of the stock to define where the boundaries are.
Today I'm going to focus mostly on the boundary between what we call the critical and cautious zones. We talk about the limit reference point. This defines the boundary between these two zones. When the stock is below this limit reference point and in the critical zone, it's considered to have suffered serious harm, and this is really a place we don't want our stocks to be.
If we look at the graph of the long history of northern cod, it goes back to about the 1960s. It was a huge stock back then but the stock declined steadily for many years after. It rebounded slightly after Canada got an extension of jurisdiction to 200 miles in the late 1970s. The stock then stabilized through the 1980s, and then it crashed very suddenly in the early 1990s.
When the stock fell below the level of the 1980s, we found that it no longer produced good recruitment; it didn't produce good numbers of young fish. It also had much lower productivity. In fact, it had suffered serious harm. Hence, the limit reference point has been defined as the average spawning stock biomass observed by the stock through the 1980s. This spawning stock biomass, or SSB as we call it, can be derived in a number of different ways. In this chart on slide 4, the blue line is derived from a complex stock assessment model, but it can also be derived somewhat more simply using some other metrics in which we measure the spawning biomass. The black bars indicate DFO's research vessel survey spawning biomass index. You can also use that to define your limit reference point and calculate it. It's simply the average value through the 1980s.
Turning to the next slide, “Scientific Data on Northern Cod”, what sources of information do we scientists have to assess stock status? We have a long history on northern cod, and a lot of information has been collected, but for us, really the most important things are time series data collected in a consistent manner. These are what really count when we're assessing fisheries resources.
Before the moratorium, we had four main pieces of information about northern cod. We had catch information, which I would argue was quite poorly monitored. We also had research vessel surveys conducted by DFO, mainly from 1983 onwards. We also had commercial catch rate information, but this came only from large offshore vessels fishing well away from the coast. We didn't have information from the inshore fisherman about their catch rate trends in the inshore. That issue was addressed quite heavily around the time of the moratorium. We also had information from cod-tagging studies, and these are ongoing today.
In the post-moratorium period we have several new sources of information. We have more catch information and I think we have much better monitoring of our fishery, principally through the dockside monitoring program. We also have an extended time series of DFO research vessel surveys going right up to 2016; these are done annually. We also have an expanded tagging program and we're also using the latest technology for tracking fish migrations and movements—that's acoustic telemetry.
We've also developed logbooks for inshore harvesters to record their catch rate information, and we've put in place a sentinel fishery. Both of these provide us with time series information about catch rate trends from inshore fishermen.
The fishermen also fill out annual questionnaires, which they provide to us at our assessment meetings.
We have other initiatives like acoustic surveys, and we do beach seine surveys of small cod in the nearshore zone. We also have ecosystem science, and the department has an ecosystem-based management approach, much more important in decision-making now.
For northern cod, in an ecosystem context, we really focus on two issues: what are the key predators of cod, and what are the key prey?
As many of you will know, for northern cod, capelin is a key prey. It's very important in sustaining the stock.
The latest northern cod assessment was conducted in March 2016, about six months ago. The participation was by DFO scientists and managers, academia, various representatives from industry sectors, first nations, and NGOs. These are open meetings with wide participation. The agreement and the conclusions of these meetings is now by consensus. This is not a bunch of scientists in a room coming up with a stock assessment. There's broad participation, and everyone has to agree with the meeting conclusions before they're written down.
Another significant development occurred in March 2016. We have a new stock assessment model that integrates a lot of information from several different sources. It does a much better job of accounting for uncertainty in stock assessments, and it's considered a huge advancement in methodology. This has been contributed mainly by academic colleagues. It's able to integrate an extensive range of biological information about the stock.
If we look at some of the more recent assessment results, these charts show two scaled catches of cod from our DFO autumn research vessel survey. Typically, we go out and do 350 or so tows with the research trawl, tow them for 15 minutes along the ocean floor, and record everything that's captured. This takes about two and a half months, with two vessels fishing 24 hours a day.
The left panel shows the catches from about a decade ago. As you can see from the scale, they're very small. There were no big catches at all. Most catches have less than 10 fish in the trawl. This was the picture for more than a decade, but after 2005, and as we move forward to 2015, you can see there's a substantial increase. Now we have many sizeable catches of cod, large ones in some areas, and there's considerable improvement over much of the stock area. The only exception seems to be the southern portion of the stock range, in the southern part of what we call NAFO division 3L.
These two graphs summarize some of the latest assessment results. They show trends in stock size from 1983 onwards. There are two metrics shown here. On the left we have the numbers or the stock abundance, and on the right, the total weights, the stock biomass. This is further subdivided into the biomass of all fish and then the spawning stock biomass, which is just the total weight of all the spawning individuals in the population.
Both show similar trends. They are high in the l980s, crash in the early 1990s, are low for a least a decade, and are now increasing, especially in the last decade. In fact, the numbers have increased 4.5-fold in the last decade, and the biomass has increased twelvefold in the last decade.
Our assessments produce estimates of the numbers of young fish each year. These are key to stock rebuilding—what we refer to as recruitment. These show similar overall trends to the abundance and biomass I've just shown you. These were highly variable in the 1980s but at a generally high level. Then there was consistently very low production of young fish for many years, about two decades, but now it's improving.
The last two groups of young fish we have seen in our surveys are now considerably improved, and these represent about 25% of what we saw for those ages in the 1980s. As I mentioned at the beginning, we have to put our assessment results in the context of a precautionary approach framework. Where is the stock relative to this limit reference point I talked about, this average spawning biomass of the 1980s? We use our assessment estimates for each year.
We divide each one by the average for the 1980s and then we can simply re-graph the results and express each annual value as a percentage of what we saw in the 1980s, or as a proportion. This allows us to graph out where the stock is, relative to our limit reference point.
If you look at the chart, you'll see the line of dashes. That's the limit reference point that defines the boundary between the critical and cautious zones, and the solid line is where the stock is. Clearly, you can see the stock improvements in the last decade. This quantifies them with respect to the limit reference point. The stock has improved from 3% in 2005 to 34% in 2015. The central take-home message from this chart is that we do have good growth in the stock in recent years, but it's not fully recovered. It still has a considerable way to go, but certainly we seem to be in a period of optimism.
The last slide is on the next steps for science on northern cod. As my colleague mentioned in his introductory remarks, new investments in ocean science are under way, with new staffing and funding, some of it directed towards northern cod directly. We'll also be continuing and enhancing our stock and ecosystem monitoring initiatives and will be using the latest technologies. We also have several new partnerships and collaborations with academia that are about to begin. Many of you will have heard about the recent announcement of funding that went to Dalhousie, Memorial University, and, in fact, UPEI. A portion of those funds will be directed towards research on northern cod, and the same is true for the other two issues I've mentioned there. With all these initiatives in place, we hope that northern cod will continue to grow in the coming years and once again become one of our important and valuable fisheries resources.
Thank you, Mr. Chairman, for the opportunity to present this information.
Thank you, members of the committee. That concludes my presentation.
