State of resources reporting

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1 Ministry of Natural Resources State of resources reporting Regional report: Lake sturgeon in the Moose River Basin December 2008 More effort has been directed at understanding the biology of lake sturgeon in the basin than any other fish species. Figure 1. Juvenile lake sturgeon. Illustration by Joseph R. Tomelleri. Lake sturgeon (Acipenser fulvescens) (Figure 1) are a unique and important part of the diversity of life in rivers of the Moose River Basin. They can be a major component of these river ecosystems and make up a significant portion of the total mass of fish in a river. Lake sturgeon were remarkably successful at adapting to life in open, big-river habitat but they now face an uncertain future. Over-harvesting, habitat loss from the construction and operation of dams, and other factors have reduced the number and distribution of lake sturgeon across their historical range. include walleye, northern pike, whitefish, brook trout, lake sturgeon, and several baitfish. Some fish species such as smallmouth bass, yellow perch, and brown bullhead are becoming more common. Historically, the Moose River Basin was an inter-connected network of large waterways which provided abundant and diverse habitats for lake sturgeon at all stages of their life. Major hydroelectric (waterpower) development in the late 1930s transformed some sections of these free-flowing, big rivers into a series of broad, deep runs and artificial lakes (reservoirs) separated by dams. These regulated river systems may not provide ideal habitat for lake sturgeon. Increasing demands for clean, renewable energy are driving further development of Ontario s large river systems. The Moose River Basin in particular has the potential to provide about one-half of the province s waterpower targets by Most of the development potential in the basin is in waters where lake sturgeon are found. Legend Moose River Basin This report provides information about the state of lake sturgeon in the Moose River Basin and the factors influencing them. It also presents information about what is being done to help ensure the long-term survival of this species. The Moose River Basin Thunder Bay James Bay Moosonee Moose Factory Timmins The Moose River Basin (Figure 2) drains about 109,000 square kilometres in northeastern Ontario. This unique watershed is dominated by an extensive network of rivers and streams. All waters flow north and converge to form the Moose River which empties into James Bay. The rivers of the Moose River Basin have diverse fish communities with 15 to 28 known fish species. The larger rivers tend to contain a higher number of different species. Fish species typically North Bay Sault Ste. Marie Sudbury Ottawa Toronto Figure 2. Location of the Moose River Basin in Ontario. 1

2 Ecology of the lake sturgeon Lake sturgeon are Ontario s largest and longest-lived freshwater fish. They can attain lengths up to three metres, weights in excess of 150 kilograms, and ages exceeding 100 years. Today, fish of this size are uncommon. However, lake sturgeon over two metres long and weighing more than 50 kilograms have been observed in the Moose River Basin in recent years. Despite being named lake sturgeon, these fish are dependent on river environments. They reproduce and spend significant parts of their lives in rivers. Their bodies are shaped to move along the bottom of shallow, moving waters. Since these fish can attain a large size, they require the abundant food sources found in bigger rivers and connected lakes. Lake sturgeon generally live on river and lake bottoms and feed on aquatic insects, mollusks, crayfish, and small fish. Lake sturgeon are migratory, moving up to 100 kilometres or more to reach a variety of seasonal habitats. In the spring, adult lake sturgeon migrate upstream to spawn (breed) in areas of fast water such as rapids, chutes, or waterfalls. They usually spawn at the same locations where they were hatched. Fast waters provide lots of oxygen, and rubble on riverbeds offers protection for incubating eggs. In the summer, fish travel long distances seeking prey in wide, shallow, and warmer parts of rivers and lakes where food is abundant. Adult fish seek out deep pools during the winter. Fish use less energy in these areas of slower water, which helps them survive the winter. History of human use Lake sturgeon have been harvested by humans in the Moose River Basin for thousands of years. Lake sturgeon had both cultural and subsistence importance to Aboriginal peoples. All parts of the fish were used: the meat for food; the skin as a container to store oil; the isinglass which lines the swim bladder as a paint stabilizer; and the pointed bones along the back as arrow heads. Today, lake sturgeon remain culturally significant and continue to be a valued food source to Aboriginal people. Initially, early settlers did not value lake sturgeon but soon learned about its various uses. Anglers and commercial fishers targeted lake sturgeon mainly for its popular smoked flesh. The oil was used in paint manufacturing and the isinglass from its swim bladder as a clarifying agent in beer and wine. Leather products were made from its skin and the eggs were used for caviar. By the early 1900s, such uses of lake sturgeon led to large increases in its harvest. Historical harvest records are incomplete. From the limited data available, it s clear annual harvests exceeded a river s production of fish in some years (Figure 3). This means more fish were taken from a population than the population was able to produce. Declining numbers of lake sturgeon resulted in the closing of the remaining commercial fisheries by the mid-1980s. Recreational angling for lake sturgeon is still common in the basin. Lake sturgeon are slow-growing and take a long time to reach reproductive age. Males generally reach sexual maturity at 15 to 20 years of age and females at 20 to 25 years of age. Typically, females spawn once every 4 to 5 years. Males spawn more frequently. Observed spawning groups range in size from fewer than 50 fish to 200 fish. The lake sturgeon s longevity, slow growth, and relatively low reproduction rates have allowed the species to survive for millennia. These same characteristics make the lake sturgeon vulnerable to human influences. Annual Harvest (kilograms of fish per hectare of river) lower Groundhog and Mattagami rivers Angling Commercial Annual Sustainable Yield upper Mattagami River Abitibi River Figure 3. Estimated harvest of lake sturgeon from three sections of rivers in the Moose River Basin. 2

3 Current state of the resource Distribution In the Moose River Basin, lake sturgeon are found throughout many of the larger rivers and their tributaries in the northern Lowlands and the central Clay Belt. They are mostly absent from the more southern Canadian Shield portions of the basin (Figure 4). Natural barriers such as waterfalls, as well as man-made dams, limit the range of lake sturgeon in parts of the basin. Currently, 15 dams are located on large rivers within the traditional range of lake sturgeon. In some of these rivers, the range of lake sturgeon has been reduced by 30 per cent or more. Abundance With some localized exceptions, lake sturgeon populations in the Moose River Basin and its large rivers (Moose, Mattagami, Abitibi, and Groundhog rivers) contain moderate numbers of fish. The Little Long Generating Station reservoir and its tributaries in the northern section of the Mattagami River support a population of roughly 12,400 adult fish. This is the largest number of adult lake sturgeon in any known population in northeastern Ontario. The closeness of spawning, nursery, and feeding habitats contribute to the high number of lake sturgeon at this location. Figure 4. Current distribution and condition of lake sturgeon populations in the Moose River Basin.. patterns of lake sturgeon Condition of Lake Sturgeon Populations s 3

4 In the southern and mid-sections of the Abitibi River, including Lake Abitibi, lake sturgeon are either scarce or no longer present. Similar trends are seen in the Mattagami River between Timmins and Smooth Rock Falls (at Highway 11). The portion of the Frederick House River from Frederick House Lake north to the Abitibi River supports a relatively small, self-sustaining lake sturgeon population. Portions of the Groundhog and Mattagami rivers north of Highway 11 support relatively robust populations of lake sturgeon. There is limited access to these areas and little development has occurred. Spruce Falls in the town of Kapuskasing marks the southern limit of lake sturgeon in the Kapuskasing River. In the Missinaibi River, lake sturgeon are only found north of Thunder House Falls. The falls are a natural barrier to lake sturgeon movement. This population has yet to be assessed. The population in the Moose River (Figure 5) between Moose River Crossing and Moosonee/Moose Factory is representative of a harvested fishery. Overall, lake sturgeon populations in the Moose River Basin tend to be average or moderately strong relative to other parts of Ontario. Southern Ontario and the Great Lakes drainage basin tend to have smaller populations due to over-harvesting in the late 1800s and subsequent habitat loss from river developments and pollution. Sturgeon populations in northwestern Ontario are similar to those in the Moose River Basin. Populations in the Winnipeg and English river systems are the exception. They have low numbers of fish. Most lake sturgeon populations in Ontario s far north have not been assessed. Remote sections of rivers probably support larger populations of lake sturgeon than sections closer to human settlements. Figure 5. The Moose River near Moose River Crossing. 4

5 Mercury in Lake Sturgeon Mercury is an element that occurs naturally in low concentrations in air, water, soil and in plant and animal matter. At one time mercury was widely used in industry. Direct discharges of mercury from major industrial sources into rivers and lakes have been virtually eliminated, although residual contamination may still exist in some locations. Industrial and other activities associated with the burning of fossil fuels are major sources of mercury today. Significant quantities of mercury enter the aquatic environment of the Moose River Basin from the atmosphere from both man-made and natural sources. Scientific evidence indicates that long-term flooding following construction of reservoirs accelerates the release of mercury into the water. When the concentration of mercury becomes high enough, it can be harmful to living organisms, including humans. Mercury is present in waters of the Moose-River Basin in several forms. An organic form known as methylmercury is easily absorbed by fish directly through their gills or indirectly from their diet. Since lake sturgeon have a long lifespan, their bodies can accumulate high levels of methylmercury over time. Larger, older lake sturgeon tend to have higher concentrations of mercury than smaller, younger ones. Fish in the northern part of the basin tend to have higher mercury concentrations than those in central locations. There are contaminants in fish other than mercury that can affect human health. Advice on safe fish consumption can be found in the Guide to Eating Ontario Sport Fish available at government and retail outlets or at ontario.ca/fishguide. Mercury body burdens for lake sturgeon in rivers of the Moose River Basin 5

6 Factors influencing lake sturgeon populations No one factor is responsible for the current state of lake sturgeon in the Moose River Basin. Major influences include: Over-fishing: Lake sturgeon populations cannot sustain more than a five per cent adult mortality rate (about 0.30 kilogram per hectare) from fishing. This means for a spawning run of 100 adult fish, no more than five fish should be removed if the sturgeon population is to be sustained. This estimate only applies to populations where there has been no prior fishing. For a fished (harvested) population, the sustainable yield is lower. With the recent collapse of the sturgeon fishery in the Caspian Sea and ongoing demand for caviar (sturgeon eggs), fishing pressure has shifted to other sturgeon populations including those in Ontario. The harvest and illegal sale of sturgeon has increased to unsustainable levels in some parts of the province. Physical barriers: Lake sturgeon s migratory needs are not compatible with many forms of waterpower development. Dams (Figure 6) typically block the upstream movement of lake sturgeon, and fish migrating downstream can be killed when they are drawn into the spillway or turbine intakes of these facilities. Dams also fragment rivers and isolate populations of fish. Once separated from broader populations, smaller subpopulations become more vulnerable to over-fishing. In addition, these subpopulations have a lower genetic diversity. Lower genetic diversity is associated with a reduced ability to adapt to environmental change and an increased risk of elimination from a particular area. Fish ladders have been successfully used to pass some fish species around barriers such as dams. However, the value of this technology for lake sturgeon is still unproven. The best locations for dams are sometimes the same locations where lake sturgeon reproduce. The operation of some hydroelectric facilities can flood or reduce water levels in important habitats, as well as alter the timing of water flow in a river. These changes can affect the availability of suitable habitat for sturgeon, alter water temperatures, influence sturgeon behaviour, and ultimately affect their population size. Industrial wastes and other contaminants: Historically, pulp and paper and lumber mills released woody debris and chemicals into river systems. Ongoing advances in waste treatment technology and new environmental regulations have reduced the amount of woody fibre that mills release. Sturgeon populations are showing Figure 6. Island Falls Generating Station, Abitibi River. signs of improvement in some of these locations. Communities and mines adjacent to rivers are also linked to the discharge of pollutants and contaminants. Legislation and monitoring help ensure provincial water quality standards are maintained. Lake sturgeon management Fishing regulations: The Ontario Ministry of Natural Resources is implementing a new model for managing the province s fisheries called the Ecological Framework for Recreational Fisheries Management. Fishing regulations are being developed for 20 new Fisheries Management Zones in Ontario. These zones are broad, ecological areas of the province that form the basis for regulating, monitoring, and reporting on Ontario s recreational fishery, including lake sturgeon. The Moose River Basin falls within Fisheries Management Zones 3 and 8. Recently, major changes were made to Ontario s existing sport-fishing regulations in response to concerns about over-fishing of lake sturgeon. Recreational anglers are no longer allowed to keep any lake sturgeon they catch. Only catch-and-release is allowed in many parts of the province including Fisheries Management Zones 3 and 8. Traditional use of lake sturgeon by Aboriginal peoples for subsistence and ceremonial purposes is not affected. The ministry will be consulting with stakeholders and Aboriginal peoples to develop a long-term, province-wide management strategy that will address issues affecting the sustainability of lake sturgeon populations. For additional information regarding the Ecological Framework for Recreational Fisheries Management and for current information on Ontario s sport fishing regulations, visit: ontario.ca/fishing. 6

7 Research: The Ontario Ministry of Natural Resources is currently investigating sampling techniques and other methods to better estimate the abundance and condition of lake sturgeon populations. The intent is to incorporate these improved methods into the province s Ecological Framework for Recreational Fisheries Management. Habitat protection: The Government of Canada s Department of Fisheries and Oceans (DFO) has the legislative authority to manage fish habitat in Ontario. The Ontario Ministry of Natural Resources will, however, review applications for development proposals on or near water. When a proposed project is likely to alter fish habitat, the ministry refers the proposal to DFO for advice on protecting fish habitat or for authorization. The ministry continues to be involved in all other fish habitat management activities, such as the Community Fisheries & Wildlife Involvement Program (CFWIP), habitat rehabilitation, and improvements. Some of these activities, such as habitat restoration, may require DFO advice or authorization. Candidate habitats for lake sturgeon restoration include spawning, nursery areas, and migration routes. Species at risk: Currently, all 24 species of sturgeon in the world are considered at risk. Under Ontario s Endangered Species Act (2007), lake sturgeon is listed provincially as Special Concern. The previous designation was Not at Risk. This higher risk level reflects concerns for the long-term sustainability of the resource. There is no imminent risk of losing lake sturgeon from the province, but a management plan for the species will need to be developed. The federal government is conducting consultations about how to list lake sturgeon in Canada under the Species At Risk Act (SARA). Changes to the federal listing could have implications for how Ontario manages lake sturgeon in the future. Further information regarding species at risk in Ontario can be found at ontario.ca/speciesatrisk. Information gaps Despite many research- and management-related studies on lake sturgeon in the last 30 years, there are still some knowledge gaps that need to be addressed to help sustainably manage lake sturgeon in the Moose River Basin. Key knowledge gaps include: Congregation habitats: Lake sturgeon congregate in groups during spring spawning, prior to migrating in the fall, and in areas where they spend the winter. At these times, they are particularly vulnerable to harvesting and poaching. Relatively few spawning areas have been identified in the basin. Less is known about other habitats lake sturgeon congregate in. Ecology of young sturgeon: Survival during the early life of lake sturgeon is crucial, yet very little is known about the ecology of young fish. Their habitats are believed to be quite different from adult fish. More work is needed to relate the abundance of eggs, larva, and juveniles to the number of mature fish and to environmental factors. Distribution and abundance: While the distribution of lake sturgeon in the large rivers of the basin can be reported on, it s unclear how many mid-sized or smaller rivers support lake sturgeon. Some of the more remote northern rivers also support lake sturgeon. The range and abundance of lake sturgeon in these rivers is also unknown. Harvest: Reliable harvest information is currently lacking for lake sturgeon in the Moose River Basin. Harvest information is important for assessing the degree of fishing pressure on local populations and for determining sustainable harvest levels. Cumulative effects of dams: The additive or cumulative effects of multiple dams on lake sturgeon populations are not understood. Currently, environmental impacts of dams are assessed on an individual project basis. Enforcement: The Ministry of Natural Resources enforcement officers give priority attention to species at risk, including lake sturgeon. Officers direct enforcement patrols to sensitive areas where lake sturgeon congregate. 7

8 State of resources reporting Outlook for the resource In contrast to some other parts of the province, the Moose River Basin has some abundant populations of lake sturgeon. Given increasing harvest demands and waterpower and associated river developments, lake sturgeon face an uncertain future. Future efforts to December 2008 restore lake sturgeon habitat may lead to the growth of some local populations in the basin s large regulated rivers. It should not be expected that lake sturgeon will return to historical levels in these waters. Since sturgeon are slow growing and slow to reach maturity and reproduce, it could take 100 years or more to noticeably improve sturgeon populations. What the public can do to help The public can participate in the stewardship of lake sturgeon by: Respecting current fishing regulations for lake sturgeon (ontario.ca/fishing) Reporting illegal poaching of lake sturgeon to the ministry s TIPS line TIPS-MNR - ( ). You can also report violations to Crime Stoppers by calling TIPS or at ( Expressing views on proposed changes to fishery regulations and river developments at public open houses or through Ontario s Environmental Registry (ontario.ca/environmentalregistry) Getting involved in local restoration or awareness projects. Figure 7. Timmins Fur Council and family members relocating lake sturgeon to the Mattagami River near Timmins. Photo by Andy Chartrand. For example, Club Navigateur La Ronde of Timmins took high school students to the Groundhog River to observe spawning lake sturgeon every spring from 1994 to This activity was part of the club s initiative to improve public knowledge of river ecology. Similarly, in 2003, Timmins Fur Council, Club Navigateur La Ronde, Ontario Power Generation Inc., and Domtar Wood Products Inc. worked together to transfer wild lake sturgeon to a section of the Mattagami River near Timmins (Figure 7). Their goal was to re-establish a lake sturgeon fishery that once existed. In 2007, young lake sturgeon were captured here indicating lake sturgeon were successfully reproducing in the area. Industry plays a role in public education and helps maintain sturgeon populations. For example, near the Little Long Generating Station on the Mattagami River, Ontario Power Generation annually relocates lake sturgeon that become trapped in the Adam Creek diversion channel during high spring flows (Figure 8). In some years, up to 1,000 fish are rescued. Figure 8. Ontario Power Generation Inc. outreach program with St. Patrick s Catholic School students at Little Long Generating Station. Photo by Darcy Heon. 8

9 Information sources ESG International Inc. and Nassagaweya Environmental Consultants Ltd Lake sturgeon population study, 2002, Little Long Reservoir, Mattagami River. Prepared for Ontario Power Generation Corp. Reference # G p. Hendry, C., D. Etheridge and G. Racine Spatial distribution patterns of lake sturgeon in northeastern Ontario. Ontario Ministry of Natural Resources, Northeast Science and Information, South Porcupine, ON. In prep. Ontario Ministry of Natural Resources, Atlas of lake sturgeon waters in Ontario. Ontario Ministry of Natural Resources, Fish and Wildlife Branch. Publications, Ontario. 12p. Ontario Ministry of Natural Resources A framework to monitor the status of lake sturgeon (Acipenser fulvescens) in Ontario. Recommendations from the workshop: developing a framework to monitor the status of lake sturgeon. March 1-2, 2005, Sault Ste. Marie, ON. MNR Publication # pp. Ontario Ministry of Natural Resources Proceedings of a workshop on the lake sturgeon (Acipenser fulvescens). Ontario Fisheries Technical Report Series No. 23. Queen s Printer for Ontario, Toronto, ON. 98p. Ontario Power Authority Integrated Power System Plan. Supply - Renewable Resources. EB , Exhibit D, Tab 5, Schedule 1. 64p. Seyler, John, Biology of selected riverine fish species in the Moose River Basin. Ontario Ministry of Natural Resources, Northeast Science & Technology, Timmins, ON. Information Report IR p. Seyler, J., J. Evers, S. McKinley, R.R. Evans, G. Prevost, R. Carson and D. Phoenix Mattagami River Lake Sturgeon Entrainment: Little Long Generating Station Facilities. Ontario Ministry of Natural Resources, Northeast Science and Information, South Porcupine, ON. Technical Report TR pp. Related information Club Navigateur La Ronde river ecology program ( Crime Stoppers ( or call TIPS Government of Canada, Department of Fisheries and Oceans (Fisheries and Oceans Canada) ( Great Lakes lake sturgeon web site provides a wealth of information on the distribution and biology of lake sturgeon in the Great Lakes basin as well as links to additional resources ( Ontario s Environmental Registry (ontario.ca/environmentalregistry) Canada s species at risk Committee on the Status of Endangered Wildlife in Canada (COSEWIC) ( and Species at Risk Registry ( Ontario s species at risk (ontario.ca/speciesatrisk) For more information For more information on the status of lake sturgeon in the Moose River Basin, please contact: State of Resources Reporting Ontario Ministry of Natural Resources Inventory, Monitoring and Assessment Section 300 Water Street, Peterborough, ON K9J 8M5 SORR@ontario.ca Web: Educating. Empowering. Engaging /12/19 v2 ISBN