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The impacts of sea lice from aquaculture on wild fish

Petition

October 19, 2005

Office of the Auditor General of Canada
and the Commissioner of the Environment and Sustainable Development
Attention: Petitions
240 Sparks Street
Ottawa, Ontario
K1A 0G6

Re: Petition seeking answers to questions arising from DFO's public statements on sea lice and aquaculture

It's frequently challenging to be a civil servant, and Fisheries and Oceans' (DFO) staff deserve a substantial amount of credit for showing up to answer often-tough questions from concerned stakeholders and interested members of the public. The issues they deal with can also be complex, emotionally charged, and thus difficult to explain—topics such as sea lice and DFO's aquaculture policy, which are discussed frequently in the media and at public meetings in British Columbia.

Unfortunately, the literature on resource management (e.g. Holling and Gunderson 2002; Understanding transformations in human and natural systems, Island Press) is also replete with examples of a "resource management pathology" in which civil servants deliberately exploit complexity and uncertainty by unfairly shifting the burden of proving environmental damage onto the public—thus hindering much-needed action.

At a recent meeting (July 20, 2005, Lynn Valley Senior's Association, North Vancouver) in which I spoke along with DFO's Senior Aquaculture Officer Andrew Thomson (Pacific Region), I mentioned that several European louse researchers have publicly chided Canadians to stop the silly and obfuscatory debate about whether farm-source lice are impacting wild fish, accept the considerable weight of evidence that lice do have impacts, and get on with honest attempts to mitigate those impacts. Many recent academic papers and workshops (e.g., SFU's November 18, 2004 Scientists Roundtable on Sea Lice; http://www.sfu.ca/cstudies/science/publications.htm#fisheries and attached*) have also reached the conclusion that lice epizootics on juvenile fish originate from farms, and that these epizootics can have population level impacts on fish (e.g., 30-50 percent mortality from lice parasitism of all sea trout, and 48-86 percent of all salmon smolts in Norway; Butler 2002: attached*).

All this prompts concerns about how DFO continues to portray the sea louse situation in public presentations and media articles (and in recent fact sheets now posted on its web), as well as why DFO has affixed an "anti-aquaculture" label in its "communications strategy" to those who question the impacts of current and inadequate aquaculture practices.

To ensure that I am hearing what I think I've been hearing—and to avoid unfairly maligning DFO, industry, or others—I sent a letter to DFO's Andrew Thomson on July 25, 2005, asking him to answer a few relevant questions. Ms. Diane Lake of DFO Communications replied to me via e-mail (attached*) on July 25 providing clarification on her department's "sea lice communications strategy" but, to date, I have not had the courtesy of a reply from Mr. Thomson on the important questions contained in my letter, and I am thus prompted to seek those answers through your assistance via this Petition to the CESD under the Auditor General Act.

The questions I have asked Mr. Thomson and still await answers on are:

1.  Did I in any way on the 20^th come off as anti-aquaculture? If so, how, specifically? What is your definition of anti-aquaculture? And why does DFO's draft "Pacific Region Sea Lice Communications Strategy" (pages 2 and 3) name Watershed Watch (and other groups and individuals) as being part of the "anti-aquaculture movement?" Is this assessment based on a professional analysis of Watershed Watch's many contributions to academic workshops and educational programs on aquaculture and wild salmon? Does it acknowledge Watershed Watch's oft-stated assertion that it is not opposed to aquaculture, but only to unsustainable forms of aquaculture? You'll surely understand that I am interested in your assessment to ensure I don't mistake such language as a convenient and derogatory label meant to serve some other purpose.

2.  I believe you claimed on the 20^th that the lice found on juvenile salmon come from many sources, including wild salmon, sticklebacks, and farmed fish. I believe I have heard other DFO personnel repeat this assertion in various meetings and media interviews. While this may be true in the broadest sense, I have not yet heard DFO venture an opinion on what percentage of lice might come from each source. I believe, though, that I did hear DFO's Dr. Dick Beamish at a May 11, 2005 Sport Fishing Institute meeting say that he had not found enough wild salmon in the Broughton to justify previous claims that wild fish are the primary source for the infections, and he thus now suspects that lice from sticklebacks play an important role in such epizootics.

Can you please clarify what you believe to be true relative to the source of these lice by answering the following:

• How many wintering salmon did Dr. Beamish find in the Broughton? What, for instance, has he reported in his BCARD (British Columbia Aquaculture Research and Development program) progress reports? How do these numbers compare with farmed fish numbers (e.g., those available on Stolt's (Marine Harvest) web)? Did I accurately hear him say that he does not now believe wild salmon to be a significant source of these lice?
• Does DFO believe sticklebacks to be the primary host source of lice in the Broughton? Or, are sticklebacks possibly a secondary or intermediate host? What species of lice have been found? How do lice numbers on Broughton sticklebacks compare to those on sticklebacks in areas without farms? If such data are available, isn't it ethical and scientifically correct to provide control comparisons? If such data are unavailable, isn't it ethical and scientifically correct to say so? Is there evidence that lice, especially L. salmonis, are capable of reproducing on sticklebacks?
• What progress has DFO made on determining the relative proportion of lice originating from these 3 sources? Doesn't an answer to this question require that DFO attempt to estimate the production of lice from farmed fish as per the "infection pressure" methods of Heuch and Mo (2001) and Butler (2002)? Have such estimates been made? Shared with the public? If not (to either), why not?

3.  You said on the 20^th that you believed risks from farm source lice to be "manageable." What do you mean by manageable? Is there a specific level of risk or impact you attach to this definition? If so, what level? Have you projected how these risks might change with varied levels of farm production (or louse thresholds)? If not, why not, especially considering the Heuch et al. (2005) assessment of Norway's less-than-hoped-for management actions (A review of the Norwegian Action Plan against salmon lice on salmonids: the effects on wild salmonids. Aquaculture 246:79-92)? Have you read this paper? Do you agree with it and find it applicable to the BC situation? If not, why not? Finally, do you believe that salmon farming as currently practiced is compatible with the prime conservation of biodiversity goal of DFO's newly-minted wild salmon policy?

4.  You claimed on the 20^th that DFO was making progress on area management strategies (e.g., as portrayed in recent papers dealing with Scotland's agreements, such as McKibben and Hay 2004; attached*). Can you please elaborate on that progress? Do you believe area management to be an effective management tool? And why/why not?

5.  Can you please share more information on the waste-modelling study you mentioned?

I also told Mr. Thomson that, while I have other questions and concerns, these are the principal ones that will help me interpret what I have been hearing. I also offered to assist him by providing any of the material I have cited (most of which is attached*).

Considering the urgency of this issue, and the benefits to Canadians of honest dialogue around resource development and management, I would appreciate assistance from your office in obtaining answers to my questions.

Sincerely,

[Original signed by Craig Orr]

Craig Orr, Ph.D.
Executive Director
604-936-9474; corr@telus.net

Attachments*:

1. Diane Lake's response to July 25 letter to Thomson
2. Peer-reviewed assessment (Heuch et al. 2005) of the effectiveness of Norway's 1997 "National Action Plan Against Salmon Lice on Salmonids."
3. Peer-reviewed paper (Morton et al. 2005) showing how infections rates declined as the result of the 2003 fallowing of farms
4. Proceedings of November 18, 2004 Scientists Roundtable on Sea Lice
5. Peer-reviewed paper (McKibben and Hay 2004) on Scottish louse production patterns and area management
6. Peer-reviewed paper (Heuch and Mo 2001) on louse production from Norwegian salmon farms
7. Peer-reviewed paper (Butler 2002) on louse production from Scottish salmon farms
8. Coastal Alliance for Aquaculture Reform briefing note on sea lice.

*[attachments not posted]

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Minister's Response: Fisheries and Oceans Canada

27 February 2006

Mr. Craig Orr
Executive Director
Watershed Watch Salmon Society
1037 Madore Avenue
Coquitlam, British Columbia
V3K 3B7

Dear Mr. Orr:

Thank you for sharing your concerns in your October 19, 2005 letter submitted under the provisions of the Auditor General Act to Ms. Johanne Gélinas, Commissioner of the Environment and Sustainable Development (CESD).

On November 3, 2005, Ms. Gélinas forwarded your correspondence to Fisheries and Oceans Canada (DFO) as Environmental Petition # 160.

You are seeking answers to questions arising from DFO's public statements on sea lice and aquaculture. More specifically, you request that DFO respond to five questions regarding statements made by Andrew Thomson A/ Director of Aquaculture Management in a presentation to the Lynn Valley Seniors Association on July 20, 2005.

In answer to your first question, Ms. Diane Lake, Communications Officer for the Pacific region has responded in an email dated July 25, 2005 (copy attached). In her email she explained that the document in question was a draft and the final version did not list any organizations. She further explained that there was no intention to malign the Watershed Watch Salmon Society.

In response to your second question, Mr. Thomson confirms that he made the statement that there are potentially many sources of sea lice, including wild salmon, sticklebacks and farmed salmon. He based that on his personal knowledge of the issue gleaned from conversations with DFO scientists. Your subsequent questions on the research findings of DFO scientists were forwarded to the principal investigators and their responses are attached in annex A.

In response to your third question, as to the risks of sea lice, Mr. Thomson was correct in his statement that the position of the department is that the risks associated with salmon farming, including the effects of sea lice, are manageable within the context of our current regulatory standards.

Furthermore, the department is committed to an adaptive management strategy, and as new information comes to light, it will make the necessary changes to its management regime to ensure the industry continues to be environmentally sustainable. The department has reviewed the paper that you cited (Heuch et al, 2004) and, as with other research on the subject, it will be considered as part of our management strategy. On-farm measures for sea lice control is in the purview of the British Columbia (BC) Provincial Government, and this paper has been forwarded to them for review. I do believe that DFO's management of the salmon farming industry is in concert with the Wild Salmon Policy. The policy clearly states that the goal, principles, and objectives of the Wild Salmon Policy will guide the regulatory actions of the department. Aquaculture operations will be regulated in a manner consistent with other human activities that may adversely affect salmon or their habitat and DFO will continue to invest in research to improve our understanding and management of this industry.

In response to your fourth question, the department has investigated area-based management in other countries through discussion with external parties and has adopted area-based management of aquaculture in New Brunswick. In BC, there have been discussions regarding the establishment of an area-based management process in the Broughton Archipelago area that involved DFO staff, provincial colleagues, ENGOS, Industry and First Nations. I support the investigation of area-based management processes to determine their applicability as a management tool in BC. Given the complex and unique interactions of government, First Nations, industry, community and Environmental organizations in BC it is difficult to predict what the effectiveness of area-based management would be.

In response to your last question, the depositional model that is currently being used in BC is more fully described in:

Cromey, CJ; Nickell, TD; Black, KD, DEPOMOD-modeling the deposition and biological effects of waste solids from marine cage farms. Aquaculture. Vol. 214, no. 1-4, pp. 211-239. 15 Nov 2002.

And

Chamberlain, J., D. Stucchi, L. Lu, C. Levings, The suitability of DEPOMOD for use in the management of finfish aquaculture sites, with particular reference to Pacific Region, Canadian Science Advisory Secretariat Research Document - 2005/035, http://www.dfo-mpo.gc.ca/csas/Csas/Publications/ResDocs-DocRech/2005/2005_035_e.htm

There is a further study currently being undertaken by Dr. Jon Chamberlain at DFO's Institute of Ocean Sciences. If you would like more information on this, I would be pleased to have my staff arrange a meeting to discuss this topic.

Thank you for bringing this matter to my attention.

Sincerely,

[Original signed by Loyola Hearn, Minister of Fisheries and Oceans]

Loyola Hearn, P.C., M.P.

Annex A: Detailed responses, prepared by DFO Science Staff to question 2.

In response to your first bullet, DFO Science does do not have quantitative estimates of the number of coho and Chinook that over-winter in the Broughton Archipelago. We do have samples of coho and Chinook that were caught on hook and line in associated areas in the late fall and winter that have a high prevalence of sea lice. In February 2004, we made 17 trawl sets over a two-day period in the Broughton region and captured 5 Chinook salmon. A troll survey conducted at the same time did not capture salmon. This information is preliminary and has yet to be published and therefore should not be cited without prior approval from the Department.

We suspect that the dynamics of sea lice production in the winter in the Broughton area may be key to understanding how both farmed and wild salmon become infected. It is possible that there may be a link with the relatively large number of sea lice on adult returning salmon (Beamish et al. 2005) and the onset of sea lice productivity that appears to start in the winter. We are examining several possible mechanisms involved in the sea lice infection of juvenile salmon. The infection may be more related to sea lice dynamics and sticklebacks than with salmonids as over-wintering hosts for sea lice. For further information please refer to:

Beamish, R.J., C.M. Neville, R.M. Sweeting and N. Ambers. 2005. Sea lice on adult Pacific salmon in the coastal waters of Central British Columbia, Canada. Fish. Res. 76:198-208.

In response to the second bullet of your question, Salmon species are the primary hosts of the marine ecoto-parasite Lepeophtheirus salmonis (a species of sea lice). The "primary host" is the host on which the parasite achieves sexual maturity. However, there are numerous examples in parasitology of intermediate and transport (paratenic) hosts on which the parasite survives but does not achieve sexual maturity. These hosts often serve to bridge an ecological gap such as may occur in parasites that are transmitted through different trophic levels (e.g., from snails to fish to birds—in which the fish "bridges" the gap). We believe sticklebacks may serve as temporary hosts and have stated this in a paper recently accepted for publication in the Journal of Parasitology (see below). In support of this we have observed that the abundance of L. salmonis on sticklebacks was consistently higher than on sympatric juvenile pink and chum salmon in 2003, 2004 and 2005 in the Broughton. Some of the highest sea lice infection levels on sticklebacks have in fact been observed in locations 20-40 miles from the salmon farms in the Broughton, and "upstream" of the farms relative to the general water current patterns. While we have observed L. salmonis on sticklebacks in the Broughton, we have seen virtually no evidence that L. salmonis matures sexually on the stickleback. We have also observed Caligus clemensi (a generalist sea lice species) on sticklebacks. There is a need for more work to understand exactly how the stickleback serves the ecological needs of L. salmonis. For example there is evidence in the literature that motile L. salmonis will "jump" from non-salmonid to salmonid hosts. We will be exploring this hypothesis with laboratory studies this spring and summer.

Regarding other areas in BC with no salmon farms and other areas with salmon farms—we have some sea lice data but mainly from juvenile salmon. Very little information is available regarding the abundance or distribution of stickleback or their infection levels by sea lice in these other areas. Sampling by other groups outside of the Skeena River and in Nootka Sound have reported small numbers of sticklebacks in their samples but none have reported the incidence of lice on the sticklebacks retained in 2003 or 2004. A summary of 2005 sampling in Nootka Sound provided January 29, 2006, reports 45 sticklebacks sampled with an infection rate of 24 percent with 23 chalimus-stage lice counted but not identified to species. Since the data outside of the Broughton are limited, we have not attempted to compare lice levels on sticklebacks in the Broughton with those that may occur in other areas. The juvenile salmon data from these other areas (with or without salmon farms) all show lower levels of lice than we have observed in the Broughton Archipelago.

At this time, we believe that the abundance of the sea lice in an area is closely linked to that of the wild salmon population and to the local oceanographic conditions that support louse survival and development. Salmon farms situated within areas of abundant wild salmon that are also oceanographically compatible to louse production will likely experience higher lice levels than those situated elsewhere. For further information you may wish to refer to:

Jones, S.R.M., G. Prosperi-Porta, E. Kim, P. Callow, N.B. Hargreaves. The occurrence of Lepeophtheirus salmonis and Caligus clemensi (Copepoda: Caligidae) on threespine stickleback Gasterosteus aculeatus in coastal British Columbia. Journal of Parasitology (in press).

In answer to your third bullet, Science Branch has not attempted to determine the "relative proportion of lice" originating from the farms, other salmonids, or sticklebacks. To make this assessment requires an estimate of the abundance of each possible host and of the incidence of mature lice on those hosts. While the potential contribution of over-wintering salmonids seems limited, we have only attempted to sample in the winter during one year. We have no estimates of marine sticklebacks in the Broughton area but their abundance and frequent occurrence in purse seine sampling and trawl surveys indicates they are highly abundant through out the year. Our sampling also indicates that stickleback can have very high sea lice loads. However, our current data indicate that most of sea lice of the species Lepeophtheirus salmonis are immature stages and the mature (adult) stages of this sea lice species have only rarely been found on sticklebacks. We could determine the abundance of Atlantic salmon on the farms and the companies monitor the incidence of sea lice, but the results will vary greatly by month, location in the Broughton, and by year. In the absence of the industry treating to control sea lice in the farms, the farms with yearling and older salmon could be a significant source of the sea lice L salmonis (with the above noted qualification about variations due to month, year, location, and oceanography) . However, we know that the industry has been treating farm fish with the chemical "SLICE" to control lice loads in the farms. The treatment frequency has increased over the past three years so it would now be misleading to simply attribute the primary source of lice in the Broughton to the farms.

Since the abundance of lice on the farms is uncertain and variable by site, month, and year, and we do not have abundance estimates of over-wintering salmonids or marine sticklebacks in the Broughton, DFO has not made the estimations you noted. DFO does provide annual media briefings concerning the results of the annual surveys conducted by Fisheries and Oceans Canada in the Broughton and will be including results obtained from other locations, and from laboratory experiments, as they become available.