SECTION 1: High Priority and Emerging Issues

As part of its mandate, DFO Science provides scientific research, advice and services focused on priority aquatic issues that may emerge suddenly or demand a place at the top of the DFO Science agenda over the long term. This section provides a sampling of issues from across Canada that occupied a priority position on the Science agenda in 2006–2007.

International Polar Year and Arctic Science

DFO Science is a major participant in the International Polar Year (IPY) 2007–2009, which began March 2007. At that time, the Government of Canada announced $150 million in IPY funding over six years, of which $100 million is for 44 science research projects. The 24 months of IPY provide a unique opportunity to gain greater scientific knowledge of our North and strengthen Canada's position as a global leader in Arctic research. DFO scientists have a prominent role among national and international partners to build an increased understanding of the oceans' role in global climate as well as the impacts of climate variability and change to Arctic marine ecosystems.

IPY is the largest-ever international program of scientific research focused on polar regions, with thousands of scientists and researchers from more than 60 nations participating. Additional information about the Government of Canada's program for IPY can be found online at: http://www.api-ipy.gc.ca

DFO is leading and engaged in several marine research projects, including the following six funded by the Government of Canada for IPY:

Project	Principal Investigator	Funding
Canada's Three Oceans	Dr. Eddy Carmack	$6.4 million
Canadian Archipelago Through-flow Study	Dr. Humfrey Melling	$3.4 million
Climate Variability and Change Effects on Chars in the Arctic	Dr. James Reist	$2.0 million
Global Warming and Arctic Marine Mammals	Dr. Steven Ferguson	$350,000
Impacts of Severe Arctic Storms and Climate Change on Arctic Oceanographic Processes	Dr. William Perrie	$500,000
Pan-Arctic Tagging of Beluga Whales	Dr. Michael Hammill	$500,000

Many Canadians, and especially students, teachers and academics in related fields, have a strong appetite for detailed information about science initiatives in the Arctic. A good place to go to learn more is the Northern Science portal of http://www.science.gc.ca/

DFO Science prepares a summary of Canadian science initiatives for the Arctic Ocean Sciences Board (AOSB), a non-governmental body that includes members and participants from research and governmental institutions in many nations. This concise report is online at: www.aosb.org

Centres of Expertise Confront Specialized Issues

Some aquatic issues arise quickly and demand expert attention. These may result from extreme change in ocean regimes, invasive species or other natural or human-impact phenomena. DFO Science has recently established Centres of Expertise, which are able to bring to bear specialized science skills related to issues such as potential environmental impacts of pesticides, hydropower impacts on fish and fish habitat, aquatic animal health research and diagnostics, aquatic chemical analysis and more. These experts are called upon to work on priority and emerging issues such as those described in this section. To learn more, visit: www.dfo-mpo.gc.ca/coe-cde/index-eng.htm

How Much Water to Extract for Human Use? Athabasca Oil Sands Water Needs

Domestic, industrial and agricultural water use is rising across Canada, putting many rivers and lakes under increasing strain. The extraction of oil from bitumen in the Athabasca oil sands in Alberta is a noteworthy example of an increasing water need.

DFO's mandate to protect fish and fish habitat results in the department having to make decisions on how much water can be withdrawn while still maintaining natural aquatic ecosystems. This field of science is called Instream Flow Needs, and combines the expertise of hydrologists, engineers and biologists to understand the relationship of fish habitat to flow. A complex array of tools and data is needed to generate hydraulic models that are used to predict the changes in fish habitat in response to altered flow regimes.

DFO's mandate to protect fish and fish habitat results in the department having to make decisions on how much water can be withdrawn while still maintaining natural aquatic ecosystems. This field of science is called Instream Flow Needs, and combines the expertise of hydrologists, engineers and biologists to understand the relationship of fish habitat to flow. A complex array of tools and data is needed to generate hydraulic models that are used to predict the changes in fish habitat in response to altered flow regimes.

During 2007, DFO Science conducted or participated in several workshops on instream flow issues, including advice on the Habitat Management Program Pathways of Effect decision support tool, the Habitat Management Program Practitioner's Guide and Decision Support Tools, two meetings of the joint Centre of Expertise on Hydropower Impacts on Fish and Fish Habitat: Canadian Environmental Assessment Agency working group on hydropower effects on fish habitat, a joint workshop of DFO and the Natural Sciences and Engineering Research Council of Canada (NSERC) on altered flow regimes; as well as a workshop to peer review a draft joint DFO–Alberta Environment water management framework for the Lower Athabasca River in the oil sands region of northern Alberta.

In this latter case, considerable research and data analysis had been conducted by the province of Alberta and DFO, and a draft water management plan had been developed. Scientists from government and academia reviewed the draft plan and examined the conclusions in light of all of the available data and the current state of scientific understanding. Advice was provided to senior management regarding the conclusions of the review in order to assist regulators in making decisions about the oil sands water needs. Proceedings can be found on the Canadian Science Advisory Secretariat (CSAS) website: http://www.dfo-mpo.gc.ca/csas

Scientific Review of the Potential Environmental Effects of Aquaculture in Aquatic Ecosystems

The DFO State-of-Knowledge Initiative is a scientific review of the potential environmental effects of aquaculture. The review covers marine finfish, shellfish and freshwater aquaculture. The fourth and fifth (final) volumes of the State-of-Knowledge papers were completed in 2006. The topics addressed in the final two volumes are:

• Role of genotype and environment in phenotypic differentiation among wild and cultured salmonids;
• Cultured and wild fish disease interactions in the Canadian marine environment;
• Trophic interactions between finfish aquaculture and wild marine fish;
• Behavioural interactions between farm and wild salmon: potential for effects on wild populations;
• Overview of the environmental impacts of Canadian freshwater aquaculture;
• Scientific review of bivalve aquaculture: interaction between wild and cultured species.

The State-of-Knowledge review papers written under the direction of DFO scientists provide the current status of scientific information and identify knowledge gaps and research needs. DFO will use this valuable information to help set its future research agenda for aquacultureenvironment interactions. The executive summaries for all five volumes can be found through the following web link: http://www.dfo-mpo.gc.ca/science/enviro/aquaculture/index-eng.htm

Tunicates: An Aquatic Invasive Species Crisis in Atlantic Canada

Invasive tunicates or “sea squirts” pose a serious threat to the Canadian aquatic environment and economy. These destructive and costly aquatic invasive species displace native species and foul aquaculture equipment, the hulls of vessels and harbour infrastructure. Some tunicates look like smothering blobs of jelly while others resemble leathery clubs. The recent arrival of four tunicate species and their substantial impacts on the mussel aquaculture industry in Prince Edward Island and Nova Scotia is raising concern that the invaders may cause similar problems in other important aquaculture areas, and that the fishing industry in Canada may also be impacted.

In the midst of this crisis, relevant research and monitoring programs on aquatic invasive species (AIS) are being developed to provide advice to industry and government agencies on management strategies. Monitoring activities are focused on early detection and the spread of AIS. All regions on the Atlantic coast are participating and coordinating their efforts to ensure efficient data gathering and sharing. This is supported by a pilot project on coordination and taxonomic support in the Gulf Region. Research activities vary from basic biology to ecosystem interaction and mitigation measures. The information generated from these research activities also contributes to the development of risk analysis and rapid response procedures; these procedures are already being used as part of management strategies and, more specifically, to respond to shellfish introduction and transfer requests.

To assist the mussel industry during this trying period, several agencies are coordinating innovative research and development projects to maximize their collective contributions. Information on the biology of these tunicates has already been used to establish effective guidelines for the movement of mussels and other fish from infested waters to non-infested areas, while minimizing the risk of new introductions or further spread of established AIS.

In Moncton, New Brunswick, Daniel Bourque is leading a research project in collaboration with Jeff Davidson (Atlantic Veterinary College) to determine the risk of spread through the processing plants. This project is providing critical information to the processing sector to minimize the risk of introduction of AIS in the receiving waters. Bourque is also collaborating with Neil MacNair (Prince Edward Island Department of Fisheries and Aquaculture) and Benedikte Vercaemer on a research project comparing the reproductive cycles of Ciona intestinalis in Prince Edward Island and Nova Scotia.

Andrea Locke is leading a research project on the natural dispersion of tunicates with the use of oceanographic models developed by Joel Chassé. This project will contribute indispensable information for the development of risk analysis. Thomas Landry and Chris McKindsey are leading a project that examines the effect of human activities on the ability of invasive tunicates to establish and thrive in Prince Edward Island. These and other research projects on invasive tunicates all contribute to the establishment of a rigorous and effective program on AIS for the benefit of all Canadians.

Biological Risk Assessment of Invasive Tunicates

In view of the significant negative impacts on aquaculture and biodiversity, the Centre of Expertise for Aquatic Risk Assessment undertook a risk assessment, led by Tom Therriault and Matthias Herborg of DFO Pacific, to inform management and policy. Five tunicate species were considered: three colonial (golden star tunicate, Botryllus schlosseri; violet star tunicate, Botrylloides violaceus; Didemnum sp.) and two solitary (club tunicate, Styela clava; vase tunicate, Ciona intestinalis).

Biological risk assessments were conducted for each species for both the Atlantic and the Pacific coasts using information contained in biological synopses, environmental niche modeling and an expert opinion survey. With the exception of C. intestinalis on the West coast (moderate ecological risk), all species were found to be of high ecological risk on both coasts, whereas the genetic consequences for all were deemed to be moderate. They also considered the risks posed by pathogens, parasites and fellow travellers. The results were peer reviewed by international tunicate, aquatic invasive species and aquaculture experts at a workshop in Charlottetown, Prince Edward Island in March 2007. The comments and decisions from that meeting are currently being incorporated into a final assessment to be published as a CSAS research document.

Japanese Skeleton Shrimp Invade Quebec Waters

In the Gulf of St. Lawrence, Chaleur Bay and the Magdalen Islands, 200,000 individual Japanese skeleton shrimp may occupy a single square metre. The invasive amphipod crustacean, Caprella mutica, is native to the Japan Sea and measures up to 35 mm long. Work carried out at the Maurice Lamontagne Institute by Marcel Fréchette, Bernard Sainte- Marie and Christian Turcotte, in cooperation with Chaleur Bay mussel growers, is designed to improve the understanding of the nature of the interactions between C. mutica and mussels and to develop means for controlling this “epidemic.” After a floating larval stage, mussels develop into “spat,” a juvenile stage during which they attach to floating surfaces such as seaweed or ropes to mature. The possible mechanisms by which C. mutica could harm the collection and growth of mussel spat include direct predation on mussel larvae or recently established spat, competition for space and food on and around the collectors, and interference with the feeding of young mussels. To date, the work has provided a better understanding of the biology of skeleton shrimp, but the results are inconclusive regarding the effects of C. mutica on mussel spat.

Devil's Lake: Concern about Cross Border Traffic in Freshwater Invasive Species

DFO researchers are currently conducting a fish pathogen and parasite survey under the direction of the International Joint Commission. In keeping with DFO's mandate under the Fisheries Act, the goal is to inform decision making in an intervention to an international dispute between the U.S. and Canada. At issue is the diversion of waters, as of June 2007, from the previously land-locked Devil's Lake into the Sheyenne River via an unfiltered outlet canal constructed by the State of North Dakota. The unfiltered diversion waters enter into the Red River Basin via the Sheyenne River, thus into the larger Hudson's Bay drainage basin, in apparent contravention of the International Boundary Waters Treaty. In Canada there is concern over the potential negative impacts to the freshwater environment, including the inflow of chemical contaminants and heavy metals, and aquatic invasive species, aquatic pathogens and parasites from the diverted waters of Devil's Lake.

For at least 10 centuries, Devil's Lake was cut off from the Red River Basin due to its elevation and water level. In recent years the water level of the North Dakota lake has risen over seven metres, and since the 1990s it has flooded annually. Although the U.S. Government committed to the building of a filtration system in a joint statement issued by both federal governments in 2005, the State of North Dakota put the flood water diversion system into operation without filtration.

National Aquatic Animal Health Laboratories Take Action Against Great Lakes Fish Virus

A deadly fish virus in the Great Lakes is causing massive mortalities in numerous fish species and is rapidly increasing its distribution to other waterways. Viral haemorrhagic septicaemia virus, or VHS, was first detected in Lake Ontario in 2005 and has subsequently been found in all the Great Lakes with the exception of Lake Superior. Additionally, VHS has been identified in inland waters in New York, Wisconsin and Michigan.

Exactly how and when this pathogen entered the lakes is uncertain, although genetic characterizations conducted by DFO scientists at the Pacific Biological Station (PBS) has provided evidence that the virus is most closely related to a strain found in the marine waters off the coast of New Brunswick and Nova Scotia, suggesting an introduction of virus from the East coast of North America. In addition to genetic studies, scientists at PBS are investigating improved viral detection methods as well as how long the virus is stable in various environmental conditions to better understand possible routes of viral transmission.

VHS poses no threat to humans but has serious potential to impact the commercial and recreational fisheries of the Great Lakes and other watersheds throughout North America. In an effort to control the spread of VHS, the Department of Fisheries and Oceans, along with the Canadian Food Inspection Agency under the National Aquatic Animal Health Program (NAAHP), is conducting a surveillance program to document the spatial distribution of the emerging pathogen and to gain insight into viral traffic patterns. The surveillance is being conducted in consultation with officials in the United States where a similar initiative is underway. This bilateral surveillance effort, which is defining VHS-infection status of aquaculture and wild freshwater fish populations in Canada and the U.S., will restore trading-partner confidence in live fish and fish product trade from regions determined free of the virus. For more information, see:
www.dfo-mpo.gc.ca/science/ aquaculture/aah_e.htm#informatio and
www.inspection.gc.ca/english/anima/ aqua/virsep/virsepe.shtml

Endocrine Disruptor Experiment Answers Critical Question about Impacts to Fish

Municipal sewage contains a mixture of chemicals, including traces of prescription drugs and hormones. Ethynylestradiol (EE2), the main component of birth control pills, is one of these compounds. While EE2 and other drugs are removed with high efficiency by sewage treatment plants, trace quantities may still be released to freshwater-receiving environments. Male fishes living in these downstream waters can have feminine characteristics. This feminization has been linked to the presence of low levels of EE2.

In a project originally headed by Dr. Karen Kidd, researchers at the DFO Experimental Lakes Area, including Drs. Paul Blanchfield, Ken Mills, Vince Palace and Mike Paterson, set out to answer the critical question as to whether these males with feminine characteristics affect the overall reproductive potential and sustainability of these populations.

Environmentally relevant concentrations of EE2 were added to Lake 260 at the Experimental Lakes Area from 2001 to 2003. The effects of the EE2 were studied in several species of fish that live in the lake. Biochemical changes were most evident in the minnow species, and the fathead minnow was impacted more than other species. Male fathead minnows quickly developed feminine characteristics and after two years there were very few normal males in the population. Because there were so few normal males, reproduction in this population dropped drastically and the species was almost eliminated from the lake where EE2 was added. Lake trout fatness and survival also decreased, probably because there were fewer minnows to eat.

This Canadian experiment was the first of its kind in the world and showed that low concentrations of contaminants that are discharged from sewage treatment facilities can cause decreases in fish populations. The evidence for this was strengthened when the fathead minnow population quickly recovered in Lake 260 upon terminating EE2 additions.

Potential Impacts of Pesticides on Fish

Applying pesticides to maximize crop yield is recognized as an important part of agricultural practice. In Canada, the use of these chemicals is regulated by the Pest Management Regulatory Agency (PMRA), a branch of Health Canada. In support of these regulations, the Department of Fisheries and Oceans established the Centre for Environmental Research on Pesticides (CERP) at the Freshwater Institute in Winnipeg. The scientists of CERP perform experiments in the laboratory and also study wild fish populations in areas where pesticides are applied to ensure that pesticide regulations are protecting fish and their habitat.

One of the model systems studied by CERP is Twenty Mile Creek, a Great Lakes tributary that originates near Hamilton and flows along the Niagara escarpment, eventually emptying into Lake Ontario near St. Catharines. As it flows, Twenty Mile Creek travels through several types of agricultural land where different types of pesticides are used. Corn, soybeans and wheat are dominant alongside the beginning of the creek, but below the escarpment fruit and vineyards predominate. CERP scientists have been studying reproduction and growth of wild fish and aquatic invertebrates at various locations in the creek, and collaborating with Environment Canada scientists who determine the actual concentrations of pesticides in the water at these locations.

The program emphasizes using and developing non-lethal indicators of effects, so in most cases the fish are evaluated and then released back into the creek. However, due to annual differences in temperature and precipitation — which can impact the rates of pesticide use and the growth and reproduction of fish and invertebrates — working in the field is challenging. Because of this, CERP also performs laboratory experiments that model field scenarios to better understand the links between exposure and potential effects. The results of all of these studies are reported to PMRA to ensure that fish and fish habitat are being protected.

Extreme Weather: Improving Forecasting with Computer Models

Extreme and unusual weather has a huge impact on coastal communities. This was demonstrated in April 2007 when late pack ice trapped more than 100 sealing vessels at sea off the coast of the island of Newfoundland, requiring a major Coast Guard rescue. Hundreds more crab fishing boats were locked in harbours as the ice prevented the industry from getting the fishing season underway.

Amidst concerns about extreme weather and climate change in Canada, the Centre for Ocean Model Development and Application (COMDA) of DFO Science is actively collaborating with Environment Canada and other agencies in developing improved computer models for operational atmosphere, ice and ocean forecasting for Canada. In this initiative, referred to as CONCEPTS (Canadian Operational Network of Coupled Environmental Prediction Systems), the ocean prediction system used at the French Mercator Oceanography Centre is being imported and adapted to Canadian needs. COMDA scientists are evaluating the model on domains ranging from the global ocean to the ocean basins and regional seas surrounding Canada.

In conjunction with CONCEPTS, COMDA scientists are also developing computer models for the biogeochemical properties of marine ecosystems. For example, a project coordinated by zones was initiated in 2006 to couple a model for plankton and nutrients to ocean-ice models for Atlantic Canadian waters, for use in detecting, understanding and predicting ecosystem variability.

Sea Lice

Sea lice are found around the world, in every ocean and on many species of fish. They are naturally occurring parasites that are very common on all species of adult Pacific salmon in British Columbia. In recent years much attention has focused on the concern that sea lice that occur on salmon raised in commercial aquaculture farms in open net cages may impact the survival of juvenile wild salmon species that migrate and rear in the same areas. Wild salmon can transfer sea lice to salmon farms and, if left untreated, farmed salmon can transfer sea lice back to the marine environment. Extensive research was initiated under the DFO Pink Salmon Action Plan to address this and other related concerns. In 2006 and 2007 DFO further expanded this research program by partnering with the BC Pacific Salmon Forum, university and independent researchers, and commercial salmon farm companies.

The results have shown that overall sea lice infection rates on wild juvenile salmon vary substantially between years, and also between locations within each year. For example, sea lice were significantly more abundant on both wild juvenile pink and chum salmon in 2004, compared to 2003, 2005, 2006, or 2007. The results indicate that sea lice levels have declined in recent years, and in 2007 were the lowest observed from 2003 to 2007, for both farmed salmon and wild juvenile salmon.

This research is also the first to document infection of threespine stickleback (Gasterosteus aculeatus) by the sea louse Lepeophtheirus salmonis. The sea lice infections observed every year were significantly greater on stickleback than on either juvenile pink or chum salmon. Salmon species and size, location, as well as seawater salinity were all found to be significant predictors of the number of sea lice on juvenile wild salmon. Ongoing DFO research is assessing the impact of sea lice infections on growth rates and mortality of juvenile wild salmon, and on the number of adult salmon that return to spawn in subsequent years. Learn more at: www.dfo-mpo.gc.ca/science/enviro/aah-saa/lice-pou-eng.htm

Genomics and the Mystery of Late-run Fraser River Sockeye Salmon

Researchers in the Molecular Genetics Lab at the Pacific Biological Station in Nanaimo, British Columbia, are carrying out novel genomics research to unravel the physiological and environmental factors responsible for mysterious shifts in migration timing of adult sockeye salmon returning to spawn. Late-run sockeye salmon historically migrated up the Fraser River in September and October when temperatures in the river are low. Since 1995, these fish have been entering the river in August and migrating through the river during peak water temperatures that are 5 to 6 degrees higher than they are adapted to withstand. These earlier migrations have resulted in generally high levels of migration mortality; in 2001 mortality rates reached 95 percent. This has had a devastating effect on allowable catches and has created significant conservation issues.

Using a combination of two cutting-edge technologies — telemetry and genomics — Dr. Kristi Miller and her university (UBC and Carleton) and industry (LGL Ltd, and Kintama Research) collaborators have been unraveling the physiological and environmental triggers that cue salmon to enter the river. Furthermore, they have embarked on research to identify whether the physiological condition of the salmon entering the river is contributing to their high levels of mortality. To do this, they insert radio tags and collect non-destructive biopsy samples from salmon as they are migrating down the coast, and then track the migration route of each salmon upon arrival to the river. The biopsy samples are used to assess genome-wide physiology through salmon microarrays — microscope slides each containing an incredible 16,000 genes spotted onto their surface — which assess which genes were turned on or off in fish based on entry-time or fate in the river.

The merging of these novel technologies has resulted in a detailed understanding of the physiological changes and constraints associated with spawning migration. Basically, the salmon have to reconfigure themselves at the molecular level for transition from the ocean back to freshwater conditions. The genomics research revealed strong and consistent shifts in the expression of genes associated with transitioning to fresh water in gill (important for osmotic preparation) and white muscle tissue (important for maintaining energy for swimming and reproductive loading), but found that neither osmoregulation nor energy transitioning could explain the altered entry timing. However, they found that the successful individual salmon who make it through the higher water temperature regions of the river all the way to their spawning grounds was highly correlated with the expression patterns in their gills. Moreover, the physiological link to survival in the river was present in the ocean, over 200 km from the river's mouth.