Evidence of meeting #21 for Fisheries and Oceans in the 41st Parliament, 1st Session. (The original version is on Parliament’s site, as are the minutes.) The winning word was industry.
A recording is available from Parliament.
3:55 p.m.
NDP
Fin Donnelly NDP New Westminster—Coquitlam, BC
Great. Thank you very much.
Perhaps I might squeak in one last question. Specifically looking at aquaculture systems, if you were to look at the open and closed systems, which one would you say better deals with pathogens and disease?
3:55 p.m.
Professor, Department of Zoology, University of British Columbia, As an Individual
Certainly, one of the debated topics within closed containment is that you have tight control over disease, and if you're treating the effluent that leaves that facility, you have the potential for no disease entering the environment, which is really quite good.
In terms of animals that come into the facility, they're generally hoped to be disease-free. So I would imagine closed containment would have a better capacity for regulating release of disease—and, certainly, that is something that a lot of people are excited about with closed containment.
December 8th, 2011 / 4 p.m.
Conservative
Ryan Leef Conservative Yukon, YT
Thank you, Mr. Chair, and through you, thank you to the witness for attending today.
You mentioned a bit about the balance and grey area and the unfortunate public perception of constantly focusing on negative aspects of one thing or another. When you talked about working in partnership in some of the forward studies on this, you were including industry as an involved partner in the information you're getting.
I'm wondering how industry is chosen. I'll lay out what I've heard, at least in testimony at committee, so it doesn't seem like I'm biased or trying to slide in a backhanded question on this. I'l be honest that I've heard very polarized testimony at times and we have heard industry say some very different things from other groups. Does the industry involved include open net farming as well as closed containment? I guess I'm asking if industry, which has a polar view to some of the things we've heard, is included in those kinds of forums?
4 p.m.
Professor, Department of Zoology, University of British Columbia, As an Individual
That's a great question.
As a university, we're interested in all sides of the equation. Our focus has mostly been in British Columbia, because that's where we're based, and we interact with basically all aspects. So we include industries that are predominately open net pen, which are generally receptive to at least the concept but wary about the economics of it, through to other groups that are very interested in closed containment as a sole source for aquaculture. We're quite broad about whom we would like to interact with, because we're approaching this very objectively. So that's our view on this.
4 p.m.
Conservative
Ryan Leef Conservative Yukon, YT
Thank you for clarifying that and, certainly, your testimony today has highlighted objectivity, which we greatly appreciate.
I'm going to ask if you have an answer to the following. What volume or density of fish in a closed containment, or even an open net environment, would start to have an impact on the performance of fish?
4 p.m.
Professor, Department of Zoology, University of British Columbia, As an Individual
That's a great question and, obviously, people are very interested in the answer. From the people I've talked to who are doing research on density effects on fish performance, it seems the biggest determiner of density effects is actually indirect, through water quality. So it seems that as long as you can keep the water quality good, you can have quite high densities. Open net pen systems, because you don't have control over the incoming water, tend to be at lower densities. In closed containment the number that seems to recur at a lot of the workshops that we go to is around 40 kilograms per cubic metre. But at the Freshwater Institute, for example, they've been rearing fish at even 80 kilograms per cubic metre and finding really quite good performance.
So it seems that as long as you have good control over the water quality, density per se may not be an issue at those sorts of densities.
4 p.m.
Conservative
Ryan Leef Conservative Yukon, YT
Obviously that leads to some profitability considerations. I'm just wondering if those densities, from your experience, create any sort of social consideration for this. That's partly what's influencing a lot of decisions made by the market.
Do we start to reach densities that are causing social concern, with the technological advances of a closed containment set-up?
4:05 p.m.
Professor, Department of Zoology, University of British Columbia, As an Individual
When you say “social”, do you mean in terms of the public or in terms of the fish in those systems?
4:05 p.m.
Conservative
Ryan Leef Conservative Yukon, YT
In terms of the public. Are people concerned about mass farming densities of fish?
4:05 p.m.
Professor, Department of Zoology, University of British Columbia, As an Individual
Right, yes. It's a very interesting question and I think it depends on the species you're working with.
For example, species of Arctic char actually grow best at really high densities of up to 200 kilograms per cubic metre, which is absolutely incredible. That's 200 kilograms per 1,000 litres. That's one part in five fish, and they actually get stressed at lower densities. So I think it depends a lot on the species. Salmon are schooling animals. They're used to fairly high densities. We don't know enough about density effects on social hierarchies and things like that. That's an area of current interest and something that will probably be investigated in the not too distant future.
4:05 p.m.
Conservative
Ryan Leef Conservative Yukon, YT
Great. I think I have time for a final question here.
Do you know if there are any genetic limits to fishing? We talk about protein enhancements. We're getting much better at what we do, across the board, controlling the environmental conditions, controlling the water quality. Is there any genetic limitation to what a salmon can grow to, and if there is, do we understand any of ramifications of that? We start getting into the world of basically injecting steroids into our salmon. I don't mean that's what we're doing, but that kind of analogy. Do we know of any limits?
4:05 p.m.
Professor, Department of Zoology, University of British Columbia, As an Individual
Yes, probably the world expert on that is Bob Devlin at the Department of Fisheries and Oceans in West Vancouver. He has been very interested in growth hormone transgenic fish. By introducing a growth hormone into an animal, you can greatly accelerate the rate of development. But one of the really interesting things he has found is that rainbow trout have been domestically reared for over a century, and that just through animal husbandry there has been selection for the highest growers. So domesticated rainbow trout grow much more rapidly than wild rainbow trout, and through that husbandry, it seems that we've come more or less to a limit of how fast rainbow trout can grow. If you introduce transgene into wild rainbow trout, they don't get any bigger than those selected for fast growth through husbandry.
So I think there is an upper limit to growth that is just a physiological limit, and there is some understanding of that—although there's always a lot more to be learned.
4:05 p.m.
Conservative
4:05 p.m.
Liberal
Lawrence MacAulay Liberal Cardigan, PE
Thank you very much, Mr. Chair.
Welcome, Doctor. It's a pleasure to have you at the committee. I certainly appreciate your middle-ground view. We have had witnesses, certainly, who were either on one side of the issue or the other.
First of all, having canola oil replace fish oil is interesting. Does that have any effect on the taste of the fish? Is anybody producing this on a commercial scale for fish farms, whether closed containment or open net?
4:05 p.m.
Professor, Department of Zoology, University of British Columbia, As an Individual
That's a great question.
Most fish feeds now have some vegetable proteins and vegetable lipids in them, so it's common practice, to some degree. One of the concerns is whether you are changing the nutrient composition of the animal and how does it taste? What the industry generally does is this. A few months before an animal will be harvested for market, it is put on finishing feed, and that feed then influences both the flavour as well as the fatty acid composition of the animal. Within a few months you can convert an animal back to what it would have been had it been reared on that diet all its life. So it's quite an interesting practice.
4:05 p.m.
Liberal
Lawrence MacAulay Liberal Cardigan, PE
So the food is being manufactured on a commercial basis. Also, you have likely tried the fish without removing them from the canola oil and it would definitely affect the taste. Is that right?
4:05 p.m.
Professor, Department of Zoology, University of British Columbia, As an Individual
To be honest, I don't know. We haven't eaten the fish. The fatty acid profiles were different. They weren't as different on canola as we expected them to be, so it appears that they do have some ability to compensate for that non-native diet, but we never did eat them, so we actually don't know.
4:10 p.m.
Liberal
Lawrence MacAulay Liberal Cardigan, PE
So you have never produced the fish using canola oil only and then had them tasted. It would be interesting to see how that would affect their taste.
4:10 p.m.
Professor, Department of Zoology, University of British Columbia, As an Individual
Absolutely.
4:10 p.m.
Liberal
Lawrence MacAulay Liberal Cardigan, PE
Anyhow, I would like to ask you this, being that you're a middle-of-the-road presenter. We've had lots of presentations on sea lice. As you and the committee are fully aware, the open net concept means a lot of jobs, and we've also heard some pretty heavy views against the open net concept. But I'd just like you to comment on the resistance of Slice for sea lice and how do you think that will affect open net fish farming? And how do you think it affects the environment?
4:10 p.m.
Professor, Department of Zoology, University of British Columbia, As an Individual
Yes, that is a great question and a complicated one.
The whole issue of sea lice is an interesting one, in that you are dealing with an extremely complex system.
4:10 p.m.
Liberal
Lawrence MacAulay Liberal Cardigan, PE
We've heard a lot of discussion on just how bad it is. I'd just like to hear your view.
4:10 p.m.
Professor, Department of Zoology, University of British Columbia, As an Individual
Okay.
One of the things that we were really interested in with regard to sea lice is this. A lot of the studies on the impact of sea lice are correlative studies, and we wanted to know what the specific effect of sea lice was on these juvenile, out-migrating pink salmon, which are of concern. What we did was to rear pink salmon, both wild-caught pink salmon and pink salmon leaving the river system, exposing them to different sea lice densities, from one to four lice per fish. We found something interesting. When the juvenile pink salmon were very small, less than about 0.5 grams, they were more sensitive than when they were larger than 0.5 grams. So we adopted a no-effect threshold, where we started to see effects of even one louse on the swimming performance of a juvenile pink salmon of less than 0.5 grams. But in our studies where we had fish exposed for up to a month, with one to four sea lice, we only experienced about 6% mortality. Mortality was not nearly as high as we expected, and once fish were greater than about 0.5 grams or 0.7 grams and started to develop scales, they seemed to be much more able to defend themselves against sea lice.
There is a lot of work that needs to be done to get at that exact question of how much of an impact sea lice have on the juvenile pink salmon, because we did different studies that found very different things. And the more studies that are done, the greater the body of evidence we can put together to really make an informed decision on what the impacts are.
