Jordanna N. Bergman, PhD Candidate | Department of Biology, Carleton University
The Rideau Canal Waterway, located in eastern Ontario, is a 202-kilometres continuous route that forms a hydrological connection between the Ottawa River, at Canada’s capital city of Ottawa, and Lake Ontario, at the city of Kingston. Constructed 1826 to 1832, the system was originally created for Canadian commercial shipping and national defence; today, the Rideau Canal is primarily operated for recreation. The completed Rideau Canal includes a series of rivers, lakes, and constructed channels interconnected by 24 operating lockstations that form the navigable waterway, many with adjacent water-control dams. As a National Historic Site of Canada, a Canadian Heritage River, and a UNESCO World Heritage Site, the Rideau Canal is internationally significant and, as a result, is highly regulated by the federal agency Parks Canada.Parks Canada is legally mandated to prioritize public safety, meet navigation requirements, and protect federally listed at-risk species; although their focus is not wildlife conservation, continuous management of the system has indeed supported the organisms residing within. The Rideau Canal has been described as having one of the most diverse fish assemblages (107 documented fish species) in Canada, and additionally, it supports one of the few wild urban muskellunge fisheries in North America supported by natural reproduction. Similar to most freshwater ecosystems, muskellunge in the Rideau Canal are ecologically important as apex predators and are also recreationally important as iconic sportfish.
During the Rideau Canal’s navigation season, which runs each year mid-May to mid-October, a channel along the entire waterway is maintained (minimum depth 1.5-metres) for boaters to travel safely. Outside of the navigation season, however, water levels in many reaches of the system are lowered (i.e., drawdowns). Each winter, in an 8.2-kilometre stretch of the waterway from Black Rapids Lockstation (45.321438, -75.698007) to Long Island Lockstation (45.250954, -75.702111), water levels are lowered by approximately 3-metres (10-feet). We refer to this section as the “Eccolands Reach” because of the nearby local Eccolands park. Most of the Eccolands Reach ranges in depth from 4.5-7.5-metres with a max depth of 9.1-metres; lowering the water levels by 3-metres for winter therefore significantly reduces the amount of habitat available for aquatic animals to overwinter in.
Protecting habitat – critical habitats in particular – plays a key role in effective conservation. Critical habitat is defined as “the habitat that is necessary for the survival or recovery of a (listed) wildlife species,” and specific to aquatic species, critical habitat includes “areas on which aquatic species depend directly or indirectly in order to carry out their life processes.” Thus, any area that supports a life history process necessary for the survival of a species would therefore be considered “critical.” Though not explicitly stated, habitats which supports overwintering of aquatic organisms in Canada are consequently critical. Winter in North America is already an ecologically challenging season for freshwater fishes, and annual winter drawdowns can exacerbate challenges fish are already experiencing like reduced habitat and refuge from areas with lethal dissolved oxygen levels. Our goal is to not wait until it’s too late, and instead take proactive measures to ensure critical habitat of muskellunge is protected. Of serious concern to the Eccolands Reach muskellunge population are the highly urbanized surrounding lands. Previous research has shown that persistent anthropogenic disturbances and environmental modifications, like shoreline alteration, runoff from developments, and decreased water quality, can be detrimental to freshwater ecosystems, particularly to habitat quality and quantity. By discovering what areas of the Rideau Canal are most important to muskellunge survival and population health, we can proactively take steps to protect (and potentially even enhance) those areas and work against population declines. Because of the significant winter water drawdowns, and project timing, we decided to evaluate overwintering habitats first.
We use acoustic telemetry to track muskellunge movements in the Eccolands Reach. Acoustic telemetry essentially has two parts to it: 1) acoustic tags and 2) acoustic receivers. The tags are surgically implanted into muskellunge and each tag emits a “ping” every 20-seconds with a unique ID and timestamp. Acoustic receivers are deployed and sit at the bottom of the river, waiting for a tagged fish to swim by. When a tagged fish swims by a receiver and its tag emits a ping, the receiver stores that information, providing a corresponding time and date for when that individual fish was near that specific receiver. Acoustic receivers are essentially “listening stations” whereby the receivers are listening for detections (“pings”) from tagged fish. In this way, as a long as the tagged fish is within the detection range of the receiver, we can determine where each fish was and when. With the generous help and expertise of Muskies Canada Inc. (MCI) Ottawa Chapter anglers, we captured and tagged 15 muskellunge in October 2020 for our overwintering study. Eleven acoustic receivers were deployed, relatively evenly spaced out, in the Eccolands Reach to monitor fish movements. We also deployed two receivers downstream of Black Rapids (into the Mooney’s Bay Reach) to see if fish left the reach by moving over the weir, but none of our tagged muskellunge were detected downstream. Interestingly, all our muskellunge were detected only upstream of the Eccolands boat launch, many of which in November showed upstream movements, potentially in search of the best available winter habitat.
Several interesting patterns emerged from movement analysis. First, fish moved more so than I anticipated – I expected muskellunge to be detected on the same 1-2 acoustic receivers for the duration of winter, but interestingly most fish were detected consistently across several stations, moving often through habitats across a 1-mile distance. Second, most fish overwintered near tributaries where there were deep areas (4.5-6-metres/15-20-feet). Third, it appears the portion of the river beneath the Vimy Bridge is so shallow that during winter it acts as a potential barrier to winter connectivity; essentially, once ice freezes over in December, if fish were upstream or downstream of the Vimy Bridge then that’s where they were confined to until ice-off in April. To date, it is unclear to what extent winterkill events occur in the Eccolands Reach, or if events are region/site specific. If muskellunge winterkill events are occurring in certain areas upstream or downstream of the Vimy Bridge, providing a connection between those areas could offer a chance for fish to escape. It therefore could be important to increase depths beneath the bridge to allow fish to move freely. Finally, we found that several of the larger, presumably sexually mature, individuals showed increased movements in April. Evaluating spawning movements was not an original objective of our overwintering study, however it may be one of the most important findings. We believe that the increased activities we noted in April are most likely linked with muskellunge pre-spawning movements in search of spawning sites. Parks Canada does not (start to) raise water levels in the Eccolands Reach for the navigation season until early May, so if muskellunge are searching for spawning areas in April when water levels are still low, their reproductive efforts may end up unsuccessful because habitat is still so limited at that time. Fish movements are highly regulated and directed by water temperatures – if it’s a warm spring (muskellunge usually spawn when water temperatures are 9-15°C), spawning has been documented in northern-latitude lakes as early as mid-April. We have not incorporated this data yet as special temperature loggers have just been recently recovered, but we will be carefully inspecting temperature data to see when muskellunge spawning might have commenced this past spring.
We are currently in the process of finalizing data analysis and have been fortunate to collaborate with hydraulic engineers, Parks Canada scientists, researchers, and MCI anglers to ensure we have a thorough understanding of muskellunge spatial ecology. Our goal is to factor in environmental characteristics of the river, like depth and bottom composition (e.g., sand, pebbles, boulders), to determine which areas are most suitable to muskellunge. We will also be evaluating if fish size has any effect on habitat preferences, as it may be that larger fish choose different areas compared to smaller fish. Though we have investigated overwintering of muskellunge in the Rideau Canal, this is only one annual aspect of their spatial ecology; because the winter drawdowns are so considerable in this reach, we felt it was best to quickly evaluate those movements and release that information rapidly. We are, however, tracking muskellunge movements year-round in the Eccolands Reach, and will be doing so until 2023. In the spring of 2021 MCI anglers again donated their time and expertise, and with their efforts to supplement ours, we tagged an additional seven muskellunge (we currently have 23 acoustically tagged muskellunge in the Eccolands Reach). Our aim is to assess other critical habitats used, like spawning habitats, and additionally we know very little about lock connectivity. We also note that protecting habitat and connectivity is only one part of conserving muskellunge; there are several other issues that threaten the local population like water quality and invasive species. We are working with several universities, the Rideau Valley Conservation Authority, and Parks Canada to evaluate the various threats to species within the Rideau Canal. Investigating muskellunge movements is only component of my PhD research – we are also tracking the movements of several other native and invasive fish species and will be compounding that information with our muskellunge movement data to better understand overall fish connectivity in the Rideau Canal. If you’d like to find out more information about our work, you can check out Dr. Steven Cooke’s Fish Ecology and Conservation Physiology website at http://www.fecpl.ca/ or my personal website at https://jordannabergman.wixsite.com/jordannabergman.
We use acoustic telemetry to track fish in the Rideau Canal. Size-specific acoustic tags (top left) are surgically implanted into our study species so that we can monitor their movements year-round. In the Eccolands Reach of the Rideau Canal, we are focusing our efforts towards monitoring the movements of muskellunge. In other parts of the waterway, however, we are also tracking northern pike, largemouth bass, common carp, and round goby. Acoustic receivers (bottom left) are stationed beneath the waters’ surface and are essentially “listening stations” – when a tagged fish swims by one of our receivers, and that tag emits a “ping” with a unique ID and timestamp, the receiver detects and stores that information so we can later determine where each tagged muskellunge was swimming and when.
Angler and collaborator Luc LaRochelle releases a tagged muskellunge in the Rideau Canal. Note the white tag near the dorsal fin – this way, if an angler catches one of our tagged muskellunge, they can contact us to report where and when they caught their fish (there’s a unique ID # and contact info on the tag). Anglers who report tagged fish are entered in a $200 prize draw, and they also provide critical information about fish movements and health.Jordanna Bergman surgically implanting an acoustic tag into a muskellunge. After inserting the tag and suturing the incision, she takes length measurements and externally tags the fish. The entire process takes 3-4-minutes, and fish are quickly released thereafter.
By Jordanna N. Bergman, PhD Student, Carleton University and Steven J. Cooke, Professor, Carleton University
Background
The Rideau Canal Waterway is a 202 km route of picturesque lakes, rivers, and artificial canals connected by 23 active lockstations and 45 locks. Originally constructed in the mid 1800s to facilitate commercial and military transport between Lake Ontario and the Ottawa River, today the Rideau Canal is almost entirely operated to support recreational, cultural, and economic activities. In fact, the system is so iconic and unique that it received World Heritage Site designation from the United Nations. Managed by Parks Canada, the lock system is used by recreational boaters, canoeists, and kayakers during the navigation season (mid-May to mid-October) to travel throughout the waterway. With pristine aquatic habitats and one of the most diverse fish communities in Canada, the Rideau Canal is home to firstclass fishing and supports an important tourismbased industry for eastern Ontario. Trophy gamefish can be found in the waterway, including Largemouth and Smallmouth Bass (Micropterus salmoides and M. dolomieu), Muskellunge (Esox masquinongy), and northern pike (Esox lucius).
Figure 1: A black crappie externally marked with an anchor tag (circled in red). Photo by Jordanna N. Bergman.
Have you ever wondered what else might be passing through locks with you beneath the surface? There’s a chance as you travel through a lockstation, fish are travelling right alongside you. Although lockmasters, anglers, and boaters have reported seeing fish inside locks, little is known about fish movement and behaviour related to lock-and-dam infrastructure. Do fish purposefully move through locks, or is it accidental? If they do move through locks, to what extent?
Are movements species-specific and/or seasonally driven? Students in the Fish Ecology and Conservation Physiology Lab at Carleton University are using acoustic telemetry equipment and generous help from anglers to investigate fish movements and the ecological connectivity of the Rideau Canal Waterway.
Figure 2: PhD student Jordanna Bergman surgically implanting an acoustic transmitter into a northern pike in a waterfilled and padded trough. Photo by Dan Rubinstein.
Biotelemetry, the tracking of animals using electronic tags, provides information on movement patterns of wild fish necessary to conservation and management efforts. Acoustic transmitters (i.e. tags) are surgically implanted into focal fish species and emit an underwater sound signal that sends unique identification information about that specific fish to acoustic receivers. Receivers, which are strategically placed beneath the water surface throughout the waterway prior to tagging, receive the sound signals and convert them to digital data that can be used to determine tag positions.
In the summer of 2019, we acoustically tagged 245 fish; these include two gamefish species, largemouth bass and northern pike, and two invasive species, common carp (Cyprinus carpio) and round goby (Neogobius melanostomus) Additional efforts and experimental projects were focused on northern pike given that they are known to travel relatively long distances (up to 8km daily). The team deployed 90 acoustic receivers throughout the waterway in the spring and in November they will be braving the cold to retrieve them to download data and analyze fish movement patterns.
Another interesting aspect of our acoustic telemetry research involves the inclusion of invasive species. We acoustically tagged both common carp and the recently discovered round goby this past summer. Round Goby are of special concern as they are a newly introduced invasive species to the Rideau Canal. We are hopeful that we may be able to prevent their further spread by understanding, and exploiting, their spatial ecology (when and where a species distributes themselves over time to reside, avoid predation, forage, and for sexually mature individuals, reproduce). Round Goby were first documented in the canal during a scheduled water drawdown in Edmonds Lockstation in Smiths Falls in 2018. The round goby is a small (25cm max), highly aggressive, bottomdwellingfish that has been observed to predate on the eggs and young of nesting gamefish, appears to contribute to increased incidences of avian botulism, and as a result of competitive exclusion, often displaces native species to suboptimal habitat. Although our team struggled to capture round goby for weeks (a bittersweet sign, as we interpret this to mean population densities are still low) we finally identified a successful capture method using a backpack electrofishing unit. We implanted acoustic tags into 45 Round Goby. Upon retrieval of our acoustic receivers in November, round goby movements will be at the top of the list for analysis.
In addition to the aforementioned electronic tagging studies, we are also conducting an extensive external tagging study to investigate broadscale fish movements in the Rideau Canal. We are striving to tag and release 10,000 fish with external identification tags, also known as anchor tags. Besides a unique ID number, the tag also has contact information (email: carleton.tag@gmail.com and phone number: (613) 520-2600 x4377) for anglers to report their catches. By partnering with anglers who report their catches of tagged fish, we can compare the original location the fish was tagged to the recapture location, and importantly, determine if that fish passed through any barriers (e.g. locks, dams) to adjacent water bodies. To date, we have tagged approximately 4,500 fish and will continue to tag fish until we reach our goal. Tagged fish species include Black Crappie (Pomoxis nigromaculatus), Bluegill (Lepomis macrochirus), Bullhead (Ictalurus spp.), Largemouth and Smallmouth Bass, Northern Pike, Pumpkinseed (Lepomis gibbosus), Rock Bass (Ambloplites rupestris), Yellow Perch (Perca flavescens), Walleye (Stizostedium vitreum), Lake Trout (Salvelinus namaycush), White Sucker (Catastomus commersoni), Common Carp (Cyprinus carpio), and Muskellunge. To date, 171 fish have been recaptured as of October 2019, none of which were recaptured in canal reaches other than where they were initially tagged.
Figure 3: Dr. Cooke’s students ready to externally tag incoming bass at a Bass Anglers Association tournament. LR: Auston Chhor, Alexandria Trahan, Brenna Gagliardi.
Over the next three years our team will continue working towards meeting the objective of tagging 10,000 fish and acoustically tagging a variety of fish species. By analyzing acoustic telemetry data in conjunction with anglerrecapture data, we hope to better understand fish connectivity in the Rideau Canal Waterway and use that information to support economically important gamefish and simultaneously minimize invasive species impacts. If you are curious to learn more about our research, or see a video of how fish are tagged, you can check out our Facebook page: https://www.facebook.com/Cook eFECPL/ or visit our lab website at http://www.fecpl.ca/
By Alexandria Trahan1, John Anderson1, Andy J. Danylchuk3 and Steven J. Cooke1
1 Fish Ecology and Conservation Physiology Laboratory, Department of Biology and Institute of Environmental and Interdisciplinary Science, Carleton University, Ottawa, ON, K1S 5B6, Canada
2 The Ottawa River Musky Factory, John Anderson, The Ottawa River Musky Factory 106 County Road 9, Plantagenet, Ontario, Canada, K0B 1L0, Canada.
3 Department of Environmental Conservation, University of Massachusetts Amherst, 160 Holdsworth Way, Amherst, MA, 01003, USA
Autumn skies are upon us and musky are in a flurry to fatten up before winter hits. As you enjoy the time on the water with a stick bait trailing behind the boat, SLAM….your heart is now pounding as you fight that prized Muskie and successfully get it to the boat. Upon landing you notice that one of the gills was nicked by a hook, and the water around the fish is stained with blood. All you can think is, now what? Will the fish survive or is there a way to stop the bleeding? You then recall seeing a video online that went viral not long, showing Mountain Dew being poured over the gills of a bass to stop bleeding. As you look to your cooler for something even close to Mountain Dew, you then also remember the discussion and debate online by anglers, writers and scientists, with some arguing that this is indeed an approach that should be embraced, while others urging caution since no scientific study has been done yet evaluating whether carbonated beverages control bleeding and improve the survival of injured fish. With no resolve, you do the best you can with this particular musky, and end your day hoping that this debate would soon be effectively put to rest.
This is where we come in. For the past few months we have been systematically testing whether a bleeding fish should have a carbonated beverage poured over bleeding gills following capture on hook and line. Although we had hoped to work on Muskies, given their rarity and size, we selected its sister species – northern pike – for the research. Given that we test this on live fish, we first needed to demonstrate that our science had valid purpose, and that our proposed procedures were in line with criteria laid out by the Canadian Council on Animal Care. Specific to our study design was experimentally injuring gills of fish by cutting out a standardized portion of gill filaments from a gill arch (see Image 1), and then pouring a selection of carbonated liquids over the gills to see if the bleeding stopped and for how long (details below).
Image 1: Piece of a gill removed from a northern pike.
What helped us get approval was that our research would resolve the frantic online debate, as well as provide evidence as to whether pouring carbonated beverages over bleeding gills would improve the outcome for an injured fish if it had to be released.
With a scientific collection permit in hand from the Ontario Ministry of Natural Resources and Forestry, it was time to start with the systematic and controlled evaluation of this longstanding questions. As with any systematic, scientific study, we had to consider and control for as many factors as possible, including water temperature, the size of the fish, and the type, amount, and temperature of carbonated beverage to be poured on the fish’s gills. Given that water temperature has a dramatic effect on the biology of fish, we opted to focus on late spring conditions when water temperature was between 11-18 C, and late summer when the temperature was 24-27 C. To then determine what type of carbonated beverage to use, we explored the different social media platforms that revealed the most common beverage being used by anglers on fish – that being Mountain Dew and Coca Cola. We also used plain carbonated lake water as a third liquid to be poured over bleeding gills, allowing us to test whether the additives in the soft drinks made a difference or it was just carbonation. For additional scientific rigor, we included two additional groups one ‘reference’ group where the fish’s gills were cut but nothing was poured on the wound, and the other being a ‘baseline’ group where nothing was done to the fish (it was simply held in a cooler for the same sampling period as the other fish).
For the experiment, fish were angled, landed, and placed into a trough filled with lake water. Fish were then measured and had their gill colour compared to a standardized scale (see Image 2), prior to being selected for one of the five groups mentioned above. Gill colour was recorded because it is relative to the amount of blood loss, with gills full of blood (most common) being bright red, and gills with lower and lower blood flow progressively lighter and lighter, to almost becoming white if fish bleed out.
Image 2. Comparing gill colour of a northern pike against a standardized scale.
For groups where gill tissue was removed, fish were individually placed in a cooler, and evaluated for relative bleeding intensity and the time it took for bleeding to stop. Relative bleeding intensity was based on the following scale: 0, no bleeding; 1, little bleeding, hard to see; 2, obviously bleeding, easy to see; and 3, intense bleeding, pulsatile blood flow. For the ‘popped’ or carbonated lake water groups, we recorded bleeding intensity immediately before and after a set volume of liquid poured directly onto the wounded gills. This would help us evaluate claims online suggesting that carbonated beverages reduced the amount of the blood loss. For all fish, additional bleeding values were recorded at range of intervals during a 20-minute holding period. After 20 minutes of holding the vigour and condition of the fish was recorded, and fish that were not moribund were released. To test whether the temperature of the pop makes a difference, we repeated the above series of experiments comparing how bleeding is affected by Mountain Dew at both 4 C (as if the pop just came out of an icefilled cooler) to 2 C (as if the pop had been sitting in a can in a koozie on the console of the boat for a few hours). We stuck to Mountain Dew for this experiment since it was the most common beverage being used in the videos online.
For both experiments combined we caught and evaluated over 200 northern pike. We are still analyzing the data to determine whether the different carbonated beverage treatments had an effect on bleeding. Stay tuned for more details and whether you are best to keep the carbonated beverages for yourself or to share them with your fish.
A roaming muskie dubbed James Bond is helping scientists spy on muskies that are so difficult to catch, they’re called the fish of 10,000 casts.
Researchers have tracked a muskie with 007 in its identifying records from the Detroit River to the far end of Lake Erie near Buffalo to Lake St. Clair and back to Lake Erie.
That is the most well-travelled muskellunge in an international study that is tracking 111 muskies with surgically implanted transmitters to understand what these large predator fish with a mouthful of teeth are doing.
Young muskie during stocking at Orillia and Cook’s Bay
By Ian Young, Jim Kelly, and Dave Boxall
2018 marked the 14th year of the Lake Simcoe Muskie Restoration Program (LSMRP). The epitome of a true partnership, the LSMRP involves Muskies Canada, Orillia Fish and Game, Fleming College, the Becker Foundation, OFAH, Toronto Spring Fishing and Boat Show and MNRF’s Aurora and Midhurst Districts. This program aims to restore a self-sustaining Muskie population that is not reliant on stocking back into Lake Simcoe. Once plentiful in the lake, it is believed that by the 1930’s the species was almost extirpated due to a variety of reasons, including a prior commercial fishery, decreased spawning habitat quality increasing Pike numbers and a lack of catch and release ethic by anglers.
A Feasibility study conducted prior to the program’s start in 2005, determined that restoring Muskie was feasible, but likely wouldn’t be successful if the original or Kawartha strain Muskie was used to help restock the lake. Kawartha’s Muskie have proven to have little tolerance for, nor an ability to co-exist with Northern Pike whereas their cousins to the north in Georgian Bay, have long been able to co-exist. Therefore, all partners agreed that Georgian Bay strain Muskie would be used.
Since 2005, crews trap netted Muskie every spring in either Georgian Bay or nearby Gloucester Pool (considered same strain) hoping to collect as many as three families each year. But like all good things … it wasn’t easy! “If Muskie are known as the fish of 10,000 casts amongst us anglers, then they are quietly recognized as the fish of a thousand net sets for fisheries techs and biologists,” revealed long time Muskies Canada member, trap netting volunteer and LSMRP organizer Jim Kelly. “Some years we would capture several ripe male and female muskies and collect our full three families in less than two weeks while other years MNRF staff would have their nets out and check for 4 or 5 weeks and barely scrape out enough ripe Muskie for one family,” he added. Whatever the case however one thing was certain … that once the fertilized eggs were transferred over to Mark Newell – “The Muskie Whisperer” and Hatchery Manager at Sir Sandford Fleming College in Lindsay, he would work his magic and get the absolute most out of every single egg, fry and fingerling he was tasked with raising!
Over the years the actual number of Muskie stocked into Lake Simcoe has varied tremendously … from less than a hundred at the start to as many as 4,000 in 2015.
After more than 10 years of trapnetting Muskie in Gloucester Pool, crews from Midhurst and Aurora realized that fewer and fewer Muskie were being caught there so they decided instead in 2018 to join forces with their MNRF Upper Great Lakes Management Unit (UGLMU) cohorts to help trap net Muskie in Severn Sound of Georgian Bay. Here they trap netted for over three weeks in early May and although several Muskie were captured … not all were ripe and willing to yield the eggs and milt required. One very large family however was collected from a big female with plenty of eggs and in the end, this proved to be the saving grace for 2018. “Mark was able to work his magic once again and get the absolute optimal results from that one family … enough that by early summer he was able to transfer 450 summer fingerlings to MNRF’s Harwood Fish Culture Station,” said Dave Boxall long time Muskie Canada member LSMRP organizer. Here, just like Mark was able to do at Fleming, staff did an amazing job ensuring cannibalism was kept at a minimum and only a small handful of mortalities were the result. So … by November stocking time about 1,700 fall fingerlings from Fleming were ready to be stocked into Lake Simcoe and 400 from Harwood were prepared for Georgian Bay at Severn Sound. “The major preparation procedure is basically switching all of the Muskie over from a pellet based feed – over to minnows. This helps acclimate all those individuals to the type of food source they’ll need to chase down and capture in their new homes if they want to survive” concluded Dave.
It was agreed beforehand that a portion of the total stocking numbers in 2018 should go back into the waterbody where the parents came from. On November 15, a crew from MNRF Aurora District, the UGLMU and Harwood Fish Culture, braved icy and snowy conditions to travel out on Georgian Bay in their Jon Boat to release 397 Muskie. “As Wil Wegman, with MNRF Aurora District who’s been connected with the LSMRP mentioned on his Instagram and Facebook Page, many of those young Muskie were stocked around the exact same area of Severn Sound where their parents were captured in trap nets that very spring and where that very important egg collection was conducted,” said Ian.
Stocking Muskie back into Lake Simcoe occurred successfully as well. On November 3rd, over 35 volunteers from Orillia Fish and Game, Muskies Canada, Bayshore Village Community, Fleming College and the Aurora Bassmasters … converged on Barnstable Bay in Lake Simcoe, and released 500 healthy young fingerlings between 7-9 inches from Fleming. On November 6th, Fleming students travelled by boat to the south side of Georgina Island and released 587 Muskie between there and the mainland. The Talbot River was the final stop for Muskie stocking in 2018 and for at least a year while the stocking portion of the LSMRP takes a one-year hiatus in 2019. Those 589 fall fingerlings and four larger yearlings were stocked throughout the river in prime habitat with more shiners to feed on than they could eat in a lifetime.
Ian Young is past president of MCI and lead for the LSMRP for his organization. “So after stocking over 20,000 Muskie into Lake Simcoe since 2005, it looks like, at Press Time anyways, that LSMRP will be taking at least a year off from capturing Muskie in the spring for egg collections and from raising Muskie at the hatcheries and releasing fall fingerlings in November”. There are several reasons for this hiatus, including current spending and travel restrictions on MNRF District staff since the new government came into power here in Ontario,
“After 14 years we are nearing the end of the project and it is now timely to sit back and re-evaluate where the program should go from here. Without trap netting and stocking, in 2019 and beyond, I know MNRF staff would like to focus more on monitoring Lake Simcoe and it’s rivers to try and determine how successful the program has been and where all those stocked Muskie and their offspring can be found. So here at Muskies Canada, we are on board with that in a big way and we look forward to an ongoing partnership with the fine staff at MNRF. We have made some great working relationships and personal friendships with these dedicated Muskie enthusiasts and we know that won’t end anytime soon,” concluded Ian.
Quentin Rougemont1, Anne Carrier2, Jeremy Le-luyer3, Anne-Laure Ferchaud1, John M. Farrell4, Daniel Hatin5, Philippe Brodeur6, Louis Bernatchez1
1Département de biologie, Institut de biologie intégrative et des systèmes (IBIS), Université Laval, G1V 0A6, Québec, Canada 2Département de techniques du milieu naturel, Centre d’études collégiales à Chibougamau, Cégep de Saint-Félicien, Chibougamau, G8P 2E9, Canada 3IFREMER, Unité Ressources Marines en Polynésie, Centre Océanologique du Pacifique – Vairao – BP 49 – 98179 Taravao – Tahiti – Polynésie Française 4Department of Environmental and Forest Biology, State University of New York, College of Environmental Science and Forestry, 13210, Syracuse, New York, USA. 5Ministère des Forêts, de la Faune et des Parcs, Direction de la gestion de la faune de l’Estrie-Montréal-Montérégie-Laval, 201, Place Charles-Le Moyne, Longueuil, Québec, J4K 2T5, Canada 6Ministère des Forêts, de la Faune et des Parcs, Direction de la gestion de la faune de la Mauricie et du Centre-du-Québec, 100, rue Laviolette, bureau 207, Trois-Rivières, Québec, G9A 5S9, Canada
Introduction
Over the past decades, an increasing number of fish species have undergone strong decrease in their abundance due to various human activities. Such activities may prevent the free movement of fish, generates pollution and habitat loss, overfishing and many additional problems. To overcome these demographic declines, numerous stocking programs have been implemented to sustain fish populations worldwide. This is the case of the Muskellunge (Esox masquinongy) in the province of Québec, Canada. The species is renowned for his trophy-size specimens which are highly prized by anglers. However, Muskellunge has undergone strong decline in abundance during the first half of the 20th century in the waters of the St. Lawrence River, especially in the greater Montréal region. Consequently, Muskellunge from Ontario and New York State were used for stocking over 1.5 million of individuals from 1950 to 1997. From 1950 to 1965, eggs initially taken from the Chautauqua Lake (New York State, USA) were transferred to the Lachine government hatchery in Québec where fry were reared before being released into the St. Lawrence River, several of its main tributaries and inland lakes. From 1965 to 1986, adults from Lake Joseph were used as source for stocking. Finally, from 1986 to 1997, eggs from Lake Tremblant were used. Muskellunge populations from Joseph and Tremblant Lakes were originally introduced with fish from the Lake Chautauqua source (see details about stocking history in Carrier et al.).
An optimal management of Muskellunge can only be achieved through a detailed understanding of its population structure and of the extant of connectivity between distinct populations. In particular, the existence of genetically differentiated populations with some level of reproductive isolation must be taken into account for sound conservation and management practices. Moreover, genetically distinct groups of fish may evolve to local adaptation in response to particular habitat characteristics (temperature, water chemistry, etc.). Those adaptations allow fish from distinct populations to optimize their reproduction and survival in a given habitat. It is therefore necessary to preserve the natural genetic variation present within a species in order to ensure its potential to evolve and survive in an ever changing environment. Such knowledge will be fundamental to define management units for fishery management, habitat protection and restoration, which is particularly important in highly connected systems such as the St. Lawrence River and its tributaries. Finally, genetics can inform on the extent of hybridization that may have occurred between wild, local fish and fish artificially introduced by stocking.
The genetic structure and diversity of Muskellunge within the St. Lawrence River, its major tributaries and inland lakes of Québec have never been studied. Therefore, the present study has been realised to : 1) evaluate the level of genetic structure in Muskellunge, 2) measure the impact of historical stocking on the genetic structure and diversity, and 3) define evolutionary significant units relevant for population management and to maintain a sustainable resource for angling.
Sampling and genetic characteristics
A total of 662 Muskellunge have been captured in 22 sites for approximately 24 fish per location (Figure 1). Those samples were essentially obtained with the help of professional fishing guides (Mr. Marc Thorpe, Mr. Mike Lazarus, and Mr. Michael Philips), their customers, volunteer sport fishermen, and wildlife technicians. A tiny portion of a pelvic fin was clipped for each fish (1 cm², 100 mg) and preserved in alcohol for further genetic analyses in the laboratory of L. Bernatchez at Laval University in Québec. All fish were released after capture.
This extensive sampling made it possible to cover the sections of the St. Lawrence River, from the Thousand Islands region to Lake Saint-Pierre, its major tributaries and some inland lakes of Québec. The major sources of stocking were also sampled : 1) Chautauqua (New York State) and Pigeon (Kawartha Lakes system, Ontario) Lakes, 2) Joseph Lake, and 3) Tremblant Lake. Muskellunge was introduced in these last two lakes and were used as sources for stocking a few years later. Finally, Lake Traverse located in the Mauricie region of Québec has never been stocked to our knowledge and was included in our study.
DNA from individual fish was extracted from the preserved biopsies in the laboratory. This DNA was then characterized using a new sequencing technology allowing to read each DNA variation over a large part of the fish genome. It was then possible to identify for each fish, over 16 000 genetic variants. Such variants were compared among individuals and among sampling sites, which allowed quantifying the genetic diversity of the species, its population structure and document the impact of past stocking events on the genetic makeup of wild populations.
Figure 1 – Location of sampling sites.
Population genetic structure
The genetic results revealed a moderate level of genetic diversity compared with other freshwater fish species that have been studied using similar methods. The effective size of populations, estimated from genetic data, is the number of broods that reproduce effectively, thus transmitting their genetic background to their offspring. In general, the total number of fish in a population can be 10 to 100 times higher than the number of effective individuals. Effective population sizes were generally quite low among Muskellunge populations, especially for isolated lakes. In the St. Lawrence River, the estimate of the effective size was 669 for all sites grouped together. This value is considered moderate compared to other freshwater species, but reflects the unique characteristics of the Muskellunge life-cycle (high longevity, highest position in the food chain, solitary and territorial behaviours) and its typically low population density. These findings highlight the vulnerability of this species and the importance of applying specific protection measures to ensure its sustainability.
The measures of genetic differentiation and population structure suggest the existence of eight distinct genetic groups in the system under study. The first group includes the Muskellunge used as stocking sources and the sites directly derived from this source, namely Chautauqua, Joseph, Tremblant, Frontière, and Maskinongé Lakes, as well as the Chaudière and Saint-Maurice Rivers. This confirms the common origin of the muskellunge of these water bodies, all derived from the source of Lake Chautauqua (New York State). For the Chaudière and Saint-Maurice Rivers, available knowledge suggest that Muskellunge abundance was initially low in those systems, and that stocking would have established perennial populations. The second group corresponds to the l’Achigan River and the third group to the Yamaska River, which are genetically distinct from the St. Lawrence River. The fourth group consists of all sites within the St. Lawrence River, from the Thousand Islands to Lake Saint-Pierre. The fifth group is Lake des Deux-Montagnes, which is also genetically distinct from the Muskellunge of the whole St. Lawrence River. It is noteworthy that Muskellunge from Lake des Deux-Montagnes show a certain proportion of migration to Lake Saint-Louis. Most of these migratory individuals (83%) were found on the North shore of Lake Saint-Louis, which is fed by water coming from the Ottawa River. The sixth group consists of isolated lakes that have never been stocked, represented in this study by Lake Traverse. This body of water has a unique genetic makeup that needs to be preserved. The seventh group corresponds to Pigeon Lake (Kawartha Lakes system in Ontario), used for stocking to a lesser extent than other water bodies, and the eighth group is Lake Champlain.
Although the St. Lawrence River formed a single population, the genetic differentiation between individuals increased with distance between them. This pattern is a consequence of the geographically reduced dispersal of individuals across the entire St. Lawrence River. In addition, the extant of genetic variation observed in the St. Lawrence River proves to be continuous, that is, there are no real, highly differentiated genetic groups. This suggests that dispersal can occur freely from upstream to downstream, although it is obviously reduced upstream by the presence of the two major obstacles on the St. Lawrence River (Beauharnois and Moses-Saunders dams).
Figure 2 – Histogram showing the percentage of each individual belonging to the different genetic groups. Each vertical bar corresponds to an individual sampled in a given body of water and represents its degree of belonging (or mixture) to a given group. Each color represents a genetically distinct group. For example, there is considerable genetic similarity between individuals in Frontière Lake, Joseph Lake and Tremblant Lake (FRO, JOS, and TRE respectively), all of which were seeded from the Chautauqua Lake (CHQ) source. Conversely, there is great genetic distinction between Lake Traverse Muskellunge (TRA) and all other bodies of water. Orange dots : source of individuals used for sowing. Green dots : lakes and rivers where the muskellunge was absent or in low abundance before stocking. Blue dots : sections of the St. Lawrence River and des Deux-Montagnes Lake. For abbreviations meaning, see Figure 1.
Stocking effects
Fine scale analysis of genetic mixing patterns allowed us to estimate the effect of stocking on the genetic structure of populations (Figure 2). This analysis revealed that stocking had very little effect on the genetic integrity of wild populations in the St. Lawrence River. Indeed, we found very little evidence of genetic mixing of Chatauqua, Joseph or Tremblant Lakes strains used as source populations. Conversely, there is evidence of pronounced genetic mixing in some lakes and tributaries of the St. Lawrence, despite the fact that they have in most cases received smaller quantities of stocked fish than the St. Lawrence River. This is the case for the Saint-Maurice and Chaudière Rivers, as well as for Maskinongé Lake, where there was a mixture of local (represented in black in Figure 2) and introduced (represented in green in Figure 2) genetic makeups. The main hypothesis likely to explain this pattern is that stocking has had variable effects depending on the initial size of the populations being stocked. In general, it is expected that stocking done with individuals from different genetic groups, in this case individuals from distant lakes (differences in climate and habitat types), is potentially ineffective due to lack of adaptation of stocked individuals to local conditions. It is therefore possible that the individuals stocked in the St. Lawrence River had a low reproductive success and/or that hybrids resulting from reproduction were poorly adapted to local conditions, ultimately showing a low survival rate. Thus, non-native Muskellunge may have been displaced in the St. Lawrence, which potentially had a larger population size than isolated lakes or tributaries.
Management implications
Our results suggest that from a genetic point of view, the entire St. Lawrence River, from the Thousand Islands region to Lake Saint-Pierre, can be considered as a single population within which genetic differentiation of individuals increase slightly with distance. Thus, a single management unit would be sufficient on the St. Lawrence River to ensure the maintenance of genetic diversity in this system. Of course, individuals who are isolated by impassable obstacles should be managed locally. This is particularly the case of Lake St-François, enclosed by dams upstream (Moses-Saunders) and downstream (Beauharnois). The second management unit includes Lake des Deux-Montagnes, which is genetically different from the St. Lawrence River population. The third group consists of the tributaries of the St. Lawrence River, each representing a distinct unit with some nuance depending on the abundance of Muskellunge prior to stocking. Thus, l’Achigan and Yamaska Rivers showed little evidence of hybridization with stocked fish while the Chaudière and Saint-Maurice Rivers have a more pronounced genetic mixing profile with the stocking sources. The fourth group consists of lakes stocked directly from Chautauqua Lake (Joseph, Tremblant, and Frontière Lakes) which all share a strong genetic similarity with Chautauqua Lake. The fifth group includes lakes into which the Muskellunge was initially present (Maskinongé and Champlain Lakes) where apparently only modest mixing occurred. Finally, Traverse Lake is one of the few, if not the only unstocked natural population in Québec with a unique genetic makeup.
In conclusion, in systems previously unoccupied by Muskellunge or with a very low density of individuals, stocking has made it possible to sustain local populations in the long term and therefore, have helped to enhance recreational fishing activities. Although stocking has temporarily contributed to the species recruitment and to the Muskellunge fishery in the Montréal region of the St. Lawrence system (see the article of Carrier et al. in the present issue), it does not appear to have been successful in the long term, possibly because of the poor adaptation of the stocked individuals to the particular local conditions of a large river such as the St. Lawrence. However, they may have contributed to sustain the fishery on the short term (see Carrier et al. in the present issue). During your next fishing trip, for example on the St. Lawrence River or on Lake des Deux-Montagnes, you will be able to assert that you most likely caught native Muskellunge of local origin. Based on the results of this study, we recommend avoiding future stocking without detailed knowledge of stock abundance, diversity and genetic structure, and of the level of exchange between them. Actions aiming habitat protection and restoration should rather be prioritized in order to optimize the success of natural reproduction.
Acknowledgements
We express our gratitude to muskies anglers who collected most of the samples, especially to Marc Thorpe, Mike Lazarus and Michael Phillips. We thank Christopher Legard (New York State Department of Environmental Conservation) for collecting and sharing Chautauqua Lake samples. We thank Samuel Cartier for collecting Lake Champlain fish. Thanks to Chris Wilson (Aquatic Research and Monitoring Section, Ontario Ministry of Natural Resources and Forestry) for sharing Pigeon Lake DNA samples and to Christopher Wilson (Fish Culture Section, Ontario Ministry of Natural Resources and Forestry) for sharing hatcheries and stocking history between Ontario and Québec. Thanks to Shawn Good (Vermont Fish & Wildlife Department) and Jeffrey J. Loukmas (New York State Department of Environmental Conservation) for sharing historical management and stocking history of Lake Champlain. We also thank Nicolas Auclair, Florent Archambault, Rémi Bacon, Christian Beaudoin, Anabel Carrier, Chantal Côté, Julie Deschesnes, François Girard, Guillaume Lemieux, Louise Nadon, Yves Paradis, Geneviève Richard, and Éliane Valiquette for logistic, field and laboratory assistance. Funding was provided by the ministère des Forêts, de la Faune et des Parcs du Québec, Canadian Research Chair in Genomics and Conservation of Aquatic Resources, Fondation héritage faune (Fédération québécoise des chasseurs et pêcheurs), Ressources Aquatiques Québec, and Muskies Inc.
This project is part of an initiative undertaken since 2010 by the ministère de la Faune et des Parcs (MFFP) and its many partners to update knowledge about Québec Muskellunge and optimize its management. To measure the current state of the Muskellunge sport fishery in the St. Lawrence River and the des Deux-Montagnes Lake, a survey of the catches was conducted from 2010 to 2013, with the collaboration of three professional fishing guides. In the section of the river located between Montréal and Sorel and in Lake Saint-Pierre, the lower abundance of young specimens harvested by sport fishermen suggested lower recruitment of young Muskellunge in these two bodies of water, compared to Lakes Saint-Louis and des Deux-Montagnes (see Carrier et al. in the present issue for more details).
Some anthropogenic activities have a negative impact on the St. Lawrence ecosystem. They have recently resulted in a deterioration of aquatic habitats, particularly in Lake Saint-Pierre. Nearly 5 000 ha of fish breeding, nursery, and growth habitats in the floodplain has been altered due to the intensification of agricultural practices over the last three decades (de la Chenelière et al. 2014). The loss of large areas of submerged aquatic vegetation beds since the mid-2000s (Figure 1; Magnan et al. 2017) and the proliferation of benthic cyanobacteria (Hudon et al. 2012), which develop on the bottom of Lake Saint-Pierre, have also been documented. These wetlands represent growth habitats and refuges for several fish species. This situation raises fundamental questions about the potential effects of habitat loss on a large predator species such as Muskellunge. In addition, critical breeding and growth habitats of juvenile Muskellunge have never been identified in Lake Saint-Pierre, which limits our ability to properly protect and restore habitats of this species. A study was therefore initiated to monitor adult Muskellunge movements during the spawning and growth seasons, to determine habitat characteristics selected by fish and to locate breeding and rearing areas of juveniles.
Figure 1 – Abundance of submerged aquatic vegetation in Lake Saint-Pierre from 2002 to 2016 (from Magnan et al. 2017).
Methodology
Figure 2 – Radio (bottom picture) and acoustic (top picture) transmitters used for Muskellunge marking. Credit : MFFP.
The identification of movement patterns and the precise location of Muskellunge has been made possible through the use of advanced telemetry technologies.
Two types of transmitters have been inserted into the fish abdomen: an acoustic transmitter, which is detected by stationary receivers at strategic locations in the St. Lawrence River and its tributaries (Figure 2) and a radio transmitter including an external antenna visible on the ventral portion of the fish, allowing precise location of the specimens using a mobile receiver, operated from a plain or a boat (Figure 3). In spring 2017 and spring 2018, a total of about 80 fixed receivers were deposited annually near the waterbed between Montréal and the Gentilly sector (Figure 4). These receivers, recovered at the end of each autumn, continuously record the passage of tagged fish. The number of the individual, the date and time of passage are then extracted and used for migration analysis purposes.
Figure 3 – Mobile radio receiver (left picture) and fixed acoustic receiver (right picture) used to locate Muskellunge. Credit : MFFP.
This information provides information on habitat use and residence time of Muskellunge in various sections of the St. Lawrence River and its tributaries. They also help defining the periods and patterns of seasonal migration of the species. In addition, accurate, real-time fish telemetry locations provide information on the location and characteristics of adult staging sites during spring breeding and during summer and fall growth seasons.
Figure 4 – Location of fixed acoustic receptors used to measure the passage of Muskellunge tagged in Lake Saint-Pierre in 2018. The stations installed between Gentilly and Québec city, to the right of this map, were not represented.
Preliminary results
A total of 21 Muskellunge were caught by sport fishing thanks to the valuable collaboration of two professional anglers, Mr. Mike Lazarus and Mr. Marc Thorpe, and to the MFFP wildlife technicians. The fish were surgically fitted with transmitters during the fall of 2016 and fall of 2017. Females and males ranged from 38 to 52 inches in size (Figure 5). The implementation of the transmitters carried out by the wildlife technicians of the MFFP went very well. All Muskellunge were located on at least one occasion, approximately 6 to 18 months after being tagged, indicating that all individuals survived after surgery.
Ten individuals tagged in the fall of 2016 were followed by boat and plain between April 25 and May 24, 2017. During this period, which includes migration to breeding sites and spawning activities, 112 locations of individual Muskellunge were noted. The habitat selected by each individual was also characterized (vegetation, substrate, temperature, current velocity, oxygen concentration, depth, etc.). The locations recorded in the spring of 2017 showed that all Muskellunge tagged at Lake Saint-Pierre during the previous fall used the Lake Saint-Pierre area to reproduce. The data revealed that 38 % of radio tagged individuals used Lake Saint-Pierre tributaries during the breeding season (April-May). Specimens were located in the du Loup, Saint-François and Nicolet Rivers, as well as in the Chenal Tardif (a section of the Saint-François River). After breeding, these individuals migrated to feeding habitats in the St. Lawrence River. The rest of the individuals used Lake St. Pierre wetlands during the spawning season. In the spring, Muskellunge were found at depths ranging from 0.6 to 8.2 m (mean : 3.1 m), in low current velocity, mostly lower than 0.1 m/s. In the majority of cases, Muskellunge were found in habitats showing submerged vegetation of moderate to high abundance.
The analysis of movements recorded in 2017, based on data collected by dozens of fixed receivers, showed that after the breeding season, the majority of fish tagged in the fall of 2016 in Lake Saint-Pierre spent some time in this area during the summer and fall of 2017. However, during summer, 60% of the individuals made large-scale migrations towards the stretch of the river located between Montréal and Sorel. Some Muskellunge even reached the stations located near the Jacques Cartier Bridge in Montréal.
In order to track the movements of the 21 tagged individuals, the telemetry monitoring work will continue in 2018 and 2019. All the results collected during this project will enable to identify and map the preferential habitats for Muskellunge, particularly for reproduction, which could be protected or restored as needed. The preliminary results of 2017 already underline the role of the shallow marshes of Lake Saint-Pierre and some of its tributaries for the reproduction of the species. It will be important to validate these observations over the next few years, to estimate the contribution of these various sectors to the recruitment of the species and to evaluate the state of health of habitats. In addition, the long-distance migrations reported in 2017 emphasize that the management of Muskellunge and its habitats must be done at the scale of the entire studied fluvial section, including the downstream portion of the tributaries. This finding is supported by the results of the genetic structure of populations, which demonstrated the homogeneity of the genetic signature of the Muskellunge population in the St. Lawrence stretch located between Lake Saint-Louis and Lake Saint-Pierre (see Rougemont et al. in the present issue for details on population genetics).
Figure 5 – Length frequency distribution of marked Muskellunge in Lake Saint-Pierre.
Warning to anglers
If you catch a marked Muskellunge, you must release it after noting the fish and telephone number written on the tag that is inserted at the base of the dorsal fin (it is often necessary to scrape the surface of the label to clearly see the numbers therein). Be careful, it is important to avoid taking the specimen out of the water and to limit the handling time. Moreover, these tips apply to all Muskellunge catches, whether tagged or not. Then contact a MFFP biologist at the number written on the tag to provide the date, location of capture, and, if possible, pictures of the ventral portion of the fish.
Acknowledgements
We would like to thank all the partners who participated in the financing and the realization of the telemetry work. Special thanks to professional fishermen Mike Lazarus and Marc Thorpe for their support throughout the development of the study and for their participation in the capture of the specimens. Thanks also to Florent Archambault, Nicolas Auclair, Rémi Bacon, Virginie Boivin, Chantal Côté, Charles-Étienne Gagnon, Guillaume Lemieux, Yves Paradis, and René Perreault for their support and for all efforts in the field. The project is made possible by the collaboration and financial support of the ministère des Forêts, de la Faune et des Parcs, of the Comité ZIP du lac Saint-Pierre, of Muskies Canada, of the Fondation de la faune du Québec, of Thomas marine, of the Fondation héritage faune (Fédération québécoise des chasseurs et des pêcheurs) and of some private donors.
References
De la Chenelière, V., P. Brodeur et M. Mingelbier (2014). Restauration des habitats du lac Saint-Pierre : un prérequis au rétablissement de la perchaude. Le Naturaliste canadien. 138 (2) : 50-61.
Hudon, C., A. Cattaneo, A.-M. Tourville Poirier, P. Brodeur, P. Dumont, Y. Mailhot, Y.-P. Amyot, S.-P. Despatie and Y. De Lafontaine (2012). Oligotrophication from wetland epuration alters the riverine trophic network and carrying capacity for fish. Aquatic Sciences. 74 : 495-511.
Magnan, P., P. Brodeur, É. Paquin, N. Vachon, Y. Paradis, P. Dumont et Y. Mailhot (2017). État du stock de perchaudes du lac Saint-Pierre en 2016. Comité scientifique sur la gestion de la perchaude du lac Saint-Pierre. Chaire de recherche du Canada en écologie des eaux douces, Université du Québec à Trois-Rivières et ministère des Forêts, de la Faune et des Parcs. vii + 34 pages + annexes.
Anne Carrier ¹ ², Philippe Brodeur³, Daniel Hatin⁴ and Louis Bernatchez¹ ¹Département de biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, G1V 0A6, Québec, Canada
²Département de Techniques du milieu naturel, Centre d’études collégiales à Chibougamau, Cégep de Saint-Félicien, Chibougamau, G8P 2E9, Canada
³Ministère des Forêts, de la Faune et des Parcs, Direction de la gestion de la faune de la Mauricie et du Centre-du-Québec, 100, rue Laviolette, bureau 207, Trois-Rivières, G9A 5S9, Canada
⁴Ministère des Forêts, de la Faune et des Parcs, Direction de la gestion de la faune de l’Estrie-Montréal- Montérégie-Laval, 201, Place Charles-LeMoyne, Longueuil, Québec, J4K 2T5, Canada
Muskellunge is one of the most mythical and impressive fish species. Over the past two centuries, biologists and Muskellunge anglers have documented many fascinating aspects of its biology. For example, it’s impressive size (Bernatchez and Giroux 2012), its unusual migration abilities (Kerr and Jones 2017) and even its surprising reproductive behavior (Crossman 1990, Jennings et al. 2011). The history regarding Muskellunge is fascinating, as evidenced by the origin of its name and the history of its management, which reveal the particular importance of Muskellunge in Québec.
This article is a non-exhaustive historical overview of some of the most important aspects of Muskellunge management in Québec. It includes some historical references regarding the nomenclature and taxonomy of Muskellunge, its original and contemporary spatial distribution and the stocking history. This article reports the work done as part of a Master’s thesis, which first aimed at gathering available historical information that would support the interpretation of genetic data on Muskellunge in Québec waters (see article of Rougemont et al. in this issue).
Taxonomy and Québec folklore
As early as the colonization time of New France, documents from the Société Provancher mentions that the first viceroy of France, Sieur Jean-François La Rocque de Roberval, used the basin of the Maskinongé River as his fishing territory. At the time, Muskellunge was a well-known species as evidenced by the multiple presumed Amerindian roots of its name, which meant big pike, ugly pike or spotted pike (Crossman 1986, MacCaughey 1917). Gradually, these appellations have derived to become « long mask » or « elongated mask » in Québec French. Today, the two generally accepted names are « maskinongé » in Canada and « Muskellunge » in the United States, but there are between 40 and 94 common names in French only (see Mellen 1917, Chambers 1923, Weed 1927 and Crossman 1986 for an exhaustive inventory of the different names and their origin). As mentioned by Crossman (1986), probably no other fish has, in a single language, as many forms or spelling of its common name. According to Weed (1927), the number of its common names is a fairly reliable index of the extent to which a fish attracts attention. This partly explains this diverse nomenclature, but as Mongeau (1976) points out, this taxonomic confusion also certainly comes from its great resemblance to the Northern pike (Esox lucius) and the fact that it has been recognized quite lately as a different species from his cousin.
Commercial fishing and natural distribution in the 19th century
Since the nomenclature of the species was highly variable until the beginning of the 20th century, it is very difficult to interpret observations regarding the Muskellunge distribution until the 1900s. In the 19th century, Muskellunge was highly prised by native and non-native anglers and, because of the quality of its flesh and its imposing size, it contributed to a significant commercial fishery in Québec. Although today the opinions are mixed about the taste of the Muskellunge flesh, the naturalist Constantine Rafinesque mentioned in 1818 that « it is one of the best fish (…) its flesh is very delicate and divides easily like salmon, in large white patches like snow » (MacCaughey 1917). According to historical records of the Canadian fisheries management authorities (Crossman 1986), nearly 2.9 million pounds, representing approximately 192 535 Muskellunge, were harvested by the commercial fishery in Québec from 1868 to 1936. Interestingly, commercial catches of Muskellunge in the waters of the Montréal area accounted for 90 % of the landings of this species throughout the province (Fry et al. 1942). Muskellunge commercial fishing ceased in 1936.
The historical texts suggest that native Muskellunge was found only in southern Québec, even if its northern and southern distribution limits are only very slightly defined. Its distribution was likely limited to the waters of the St. Lawrence River watershed and some of its tributaries from the Ottawa River to Québec City (Small 1883, Dymond 1939, Vézina 1977). According to information available at the end of the 19th century, native Muskellunge was found from the southern border of the province (including the Champlain Lake and the Richelieu River watersheds) to Northwest of Outaouais, Laurentides, Lanaudière, and Mauricie regions (Dymond 1939). Specifically, Dymond (1939), Small (1883), Halkett (1906 and 1907), and Montpetit (1897) report that Muskellunge was present (1) in the Rideau River north of Merrickville (Outaouais, Québec), (2) in the Ottawa River south of Rapides des Joachim (MRC de Pontiac, Outaouais, Québec), south of the Petawawa River and up to Travers Lake (Algonquin Provincial Park, Ontario), and (3) in several lakes connected to the Gatineau and du Lièvre Rivers, including Gilmour, Donaldson, and Plumbago Lakes (MRC Collines-de-l’Outaouais, Outaouais, Québec). In addition, some isolated populations were discovered in 1968 after the dismantling of private fishing clubs in the Mauricie region, specifically in the des Envies River watershed, which is a tributary of the Batiscan River, where the Traverse Lake (Potvin 1973, Pageau et al. 1978) analyzed in the study of Rougemont et al. (see article in this issue) is located. Finally, according to the interpretation of Fry et al. (1942), quoted by Robitaille and Cotton (1992), the most important native population in Québec would have been in Lake St-Louis, a fluvial lake of the St. Lawrence River.
Active management period
Stocking
Gustave Prévost, director of the Muskellunge hatchery in 1962. Credit : MFFP.
Muskellunge has been one of the most stocked fish species in Québec (Dumont 1991). Prior to 1950, few Muskellunge stocking in Québec were recorded in the literature (MacCaughey 1917, Dymond 1939, Small 1883, Halkett 1906 and 1907). At the end of the first half of the 20th century, a significant decline of Muskellunge populations in the waters of the St. Lawrence River and of the Montréal Archipelago, associated with overfishing and habitat loss, raised worries and questions. Therefore, the wildlife management authorities undertook a major restoration project which included the construction of the very first Muskellunge hatchery facility in Lachine (borough of Montréal city, Québec) (Pictures 1 to 3), as well as the development of a local expertise on esocids breeding (Vezina 1977). In 1950, these actions led to the beginning of stocking, which were adapted to contemporary knowledge in 1985. Muskellunge stocking continued until 1997. During the same period, the species was also introduced, with or without success, in more than 80 Québec water bodies in order to create new opportunities and enhance existing Muskellunge populations (Vézina 1977, Dumont 1991, Vincent and Legendre 1974, Brodeur et al. 2013, de la Fontaine, Y. unpublished). In a few rare cases, Muskellunge introduction has been used in an attempt to control competing species in brook trout lakes. Introducing a top-predator into the food chain obviously had an impact on the fish communities.
Muskellunge farming began in Québec at the Lachine hatchery in 1950. Due to water supply problems, breeding was transferred to the Baldwin Mills hatchery in 1964 (now known as the Baldwin-Coaticook provincial hatchery) (Dumont 1991). Following unsuccessful attempts to breed Muskellunge from several local lakes such as Lake des Deux-Montagnes (Montréal area) and the Gilmour, Donaldson, and Plumbago Lakes (Outaouais) (MPC 1961, Vezina 1977, Crossman and Goodchild 1978), embrocated eggs were imported from the Bemus Point hatchery (New York, USA) and, to a lesser extent, from the Deer Lake hatchery (Ontario, Canada) to start production (Kerr 2001, Dufour and Paulhus 1977, Christopher Wilson and Christopher Legard, personal communication). Muskellunge from both hatcheries originated respectively from the Chautauqua Lake (New York, USA) and from Stony Lake, Buckhorn Lake, and from the Crowe River, these three last water bodies being part of the Kawartha Lakes system in Ontario. According to the information we gathered, it appears that all the lakes used by these hatcheries have also been stocked with an unknown Muskellunge source to support their respective fishery (Christopher Wilson and Christopher Legard, personal communication). Both of these hatcheries, as well as the one of Lachine, are no longer in operation.
Photo 3 – Muskellunge transport from the Lachine hatchery. Credit : MFFP
From 1965 to 1986, Joseph Lake (Centre-du-Québec, Québec) was used as a broodstock source to supply the Baldwin Mills hatchery (Dumont 1991). Subsequently, from 1986 to 1997, Lake Tremblant (Laurentides, Québec) was used as the source population. Muskellunge was originally introduced in both lakes from the American or Ontarian sources (see Figure 1 – simplified stocking history in Québec). The results of the genetic study confirmed that the American source was the most likely for both lakes.
Stocking, carried out over several decades in the Montréal area, has been effective in improving the stock status and maintaining the Muskellunge sport fishery. In fact, an analysis of Muskellunge recruitment measured from 1962 to 1977 revealed that 55 % of the annual abundance of young Muskellunge could be explained by the number of yearly stocked individuals and the abundance of young Muskellunge stocked the previous year (cannibalism
and/or competition effects) (Dumont 1991). In 1998, the improvement of the Muskellunge population structure, distributed over a long time period, and the presence of natural recruitment justified the end of stocking (Cloutier 1987, Dumont 1991). Since then, no Muskellunge stocking has been done in Québec.
Figure 1 – Simplified representation of stocking in the St. Lawrence River and some inland lakes of Québec. Arrows represent stocking events from the different source populations. Full arrows show clear mentions of stocking, while the dotted arrows reflect anecdotal mentions.
Integrating collaborative science to Muskellunge management
In parallel to the management actions undertaken by the Québec government, a general reflection on fishing practices and a growing interest in the conservation of a high quality fishery focusing on trophy-size specimens emerged, leading to the creation of Muskies Canada (Wachelka 2008a,b,c) and to the beginning of a long collaboration between muskies anglers and the Québec wildlife management authorities. Muskellunge is not vulnerable to capture by the scientific fishing gears used to monitor fish communities in the St. Lawrence River. Monitoring the sport harvest of Muskellunge through angling surveys is therefore an excellent alternative to contribute to its management and to allow evaluation of the effectiveness of the management measures.
To evaluate the status of Muskellunge stocks, a study was conducted in the 1990s in collaboration with the Montréal chapter of Muskies Canada. From 1994 to 1997, five anglers tagged and released 808 Muskellunge, mainly in the Montréal area. The results showed that a few hours of fishing were enough to catch a Muskellunge, whereas in the 1970s, an experienced angler needed approximately 100 hours of fishing to catch a single specimen. After three years of survey, 88 tagged fish were recaptured by anglers, which corresponded to a recapture rate of 11 %, considered relatively low and indicative of a total Muskellunge abundance of several thousands of specimens (Pierre Dumont, personal communication) The gradual increase in the extent of the Muskellunge size structure suggested by the fishing surveys and the presence of a natural production of young Muskellunge justified the cessation of stocking in 1998 (Dumont 1991).
To update the data on the Muskellunge fishery in the St. Lawrence River (from Lake Saint-François to Lake Saint-Pierre) and in Lake des Deux-Montagnes, a second survey was conducted from 2010 to 2013, more than a decade after stocking ended. This second study was conducted with the invaluable collaboration of three professional anglers recognized in Québec, Mr. Marc Thorpe, Mr. Mike Lazarus and Mr. Michael Phillips. A total of 2 569 Muskellunge were captured, of which 2 162 were tagged by three volunteer anglers. Of these tagged fish, 108 were recaptured. The order of magnitude of recapture rates was low in all studied sectors (3.7 % to 4.8 %). Compared to the study carried out in the Montréal area from 1994 to 1997, the recapture rate reported from 2010 to 2013 was twice lower (4.8 % compared to 11 %). Since the recapture rate is generally inversely proportional to the total abundance of a population, this result suggests that the abundance of Muskellunge in the Montréal area has increased since the stocking ended, at least for medium to high size fish, targeted by anglers.
According to archived data from 1918 to 1927, 19 % of Muskellunge caught in Lake Saint-Louis exceeded the legal minimum size of 44 inches (Figure 2). In 1973, this proportion was of 16 % and then increased to almost 50 % in the late 1990s and to 54 % during the 2010-2013 period. This improvement over several decades can be explained by stocking, combined with the enforcement of a minimum legal size of 38 inches in 1986, which has been increased to 44 inches in 1998 (Figure 2). Because of the presence of large specimens, the waters of the St. Lawrence River and of Lake des Deux-Montagnes are now identified as sites of great interest for Muskellunge anglers. In the section of the St. Lawrence River between Montréal and Lake Saint-Pierre, the low abundance of young specimens smaller than 35 inches in the Muskellunge sport harvest suggests a lower recruitment, compared to Lake Saint-Louis and Lake des Deux-Montagnes (Figure 3). This result justified the realization of a study conducted by the ministère des Forêts, de la Faune et des Parcs (MFFP) and its numerous partners that aims to identify the essential habitats of the species by using telemetry
(see the article of Brodeur et al. in this issue).
Figure 2 – Historical comparisons of the proportion of fish larger than 44 inches caught by sport fishing on Lake St-Louis. The year of introduction of minimum sizes to 38 inches in 1986, increased to 44 inches in 1998, is also represented.
The most recent fishery survey has generated some preliminary knowledge about Muskellunge migration. Thus, between 2010 and 2013, the majority of marked individuals (95 %) recaptured by the sport fishery within six months after tagging or one to two years after, were in the same body of water where they had been tagged. The distances measured between specimens capture and recapture were generally less than a few kilometers, both on a one year scale and between years (72.7 % and 58.1 % of recaptures within 5 km from the tagging location, respectively). This result suggests that, although Muskellunge can travel long distances, particularly during the breeding season, a large proportion of individuals return to specific areas corresponding generally to large vegetation beds favorable to feeding. This result demonstrates the importance of preserving and restoring the submerged aquatic vegetation beds of the St. Lawrence River. However, large-scale movements between the various sectors of the river have been observed between Lake Saint-Pierre and the Montréal-Sorel section, with distances of up to 58 km. This result was recently corroborated by the preliminary results of the telemetry study, which shows that a certain proportion of the Muskellunge tagged at Lake Saint-Pierre migrate upstream during the feeding season (see article by Brodeur et al. in this issue). These observations of large scale movements also corroborate the connectivity existing throughout the St. Lawrence River system revealed by genetic analyses.
Figure 3 – Size structure of Muskellunge caught by sport fishing during the 2010- 2013 period in the St. Lawrence River watersheds (LDM: Lake des Deux-Montagnes, LSF: Lake Saint-François, LSL: Lake Saint-Louis, MS: stretch between Montréal and Sorel, LSP: Lake Saint-Pierre). The proportion of fish greater than or equal to 44 inches, 36 to 43 inches and 35 inches or less is shown.
Future perspectives
To maintain the trophy status of the species, which can maintain and improve the quality of the Muskellunge fishery, a regular review of the stock status and management is required. Since 2010, a study aiming at gathering new knowledge on several aspects of Muskellunge biology has been conducted by the MFFP and its numerous partners. This vast study will contribute to Muskellunge management in Québec. To date, this initiative has led to a retrospective of historical management, reported in this article, to a genetic analysis of Muskellunge populations (see article by Rougemont et al. in this issue), and to a study aiming to identify essential Muskellunge habitats between Montréal and Lake Saint-Pierre. Some anglers report a recent decline in the quality of the Muskellunge fishery in some inland water bodies of Québec, which remains to be measured. Muskellunge studies based on angling surveys have thus been underway for some years in the Maskinongé Lake and the Ottawa River (see Deschesnes in this issue).
Acknowledgements
We thank the following people for their valuable collaboration. We would like to acknowledge the involvement of the Muskellunge anglers who participated to the 2010-2013 angling survey: Marc Thorpe, Mike Lazarus, and Michael Phillips. Special thanks to Peter Levick (Muskies Canada), Chris Wilson (Aquatic Research and Monitoring Section, Ontario Ministry of Natural Resources and Forestry), and John Farrell (Department of Environmental and Forest Biology, State University of New York) who shared with us many information on Muskellunge management. Thanks to Christopher Legard (New York State Department of Environmental Conservation) and Christopher Wilson (Fish Culture Section, Ontario Ministry of Natural Resources and Forestry) for sharing the Chautauqua Lake and Deer Lake hatcheries history. Thanks to Steven Kerr (retired biologist, Fisheries Section, Ontario Ministry of Natural Resources) for his invaluable advice and for sharing his knowledge on the history of Muskellunge management in Québec. Thanks to Shawn Good (Vermont Fish and Wildlife Department) and Jeffrey J. Loukmas (New York State Department of Environmental Conservation) for sharing management and stocking history of Champlain Lake. We also thank the Fédération québécoise des chasseurs et des pêcheurs, Ressources Aquatiques Québec and Muskies Inc. for their financial support. Funding was also provided by the ministère des Forêts, de la Faune et des Parcs du Québec and by the Canada Research Chair in Genomics and Aquatic Resources Conservation.
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Abstract: The reach of the Rideau River that flows through Ottawa, Ontario supports a recreational fishery for northern pike (Esox lucius) and muskellunge (Esox masquinongy). The reach is unique not only because such a vibrant esocid-based recreational fishery exists in an urban center, but that these two species co-occur.
Typically, when these species occur sympatrically, northern pike tend to exclude muskellunge. To ensure the persistence of these esocid populations and the fisheries they support it is important to identify key spawning, nursery, foraging and over-wintering locations along this reach, and to evaluate the extent to
which adults of the two species exhibit spatio-temporal overlap in habitat use. Radio-telemetry was used to track adult northern pike (N = 18; length 510 to 890 mm) and adult muskellunge (N = 15; length 695 to 1200 mm) on 73 occasions over one year, with particular focus on the breeding seasons (early April until the end of May [56% tracking effort]). For the two esocids, we observed 19–60 % overlap in key aggregation areas during each season and during the spawning period. The minimum activity (average linear river distance travelled between consecutive tracking events) and core range (linear river distance within 95 % C.I. of mean river position) were greatest in the winter and fall for northern pike and in the spring for muskellunge. On average, northern pike were considerably smaller than muskellunge and had lower minimum activities and smaller core ranges, which
could be a result of thermal biology, limited suitable habitat, prey availability or predation. Results from this study will inform future management of these unique
esocid populations and should be considered before any habitat alterations occurs within or adjacent to the Rideau River.
January 2016 – Report prepared by Steven J. Kerr for Muskies Canada Inc. and Ontario Ministry of Natural Resources and Forestry
Executive Summary
The Muskellunge (Esox masquinongy) is known as a voracious apex predator. In instances where muskellunge are extending their range, either through intentional or inadvertent introduction and natural range extension, concerns have been identified about the potential negative impacts on resident fishes and aquatic biota. This review has been conducted to assemble information on muskellunge predatory habits and diet as well as interspecific competition with other species.
Muskellunge prey on a wide variety of organisms but prefer other fishes. Predation is based largely on whatever species in available at the preferred size. There is a considerable amount of evidence to indicate that Muskellunge prefer soft-rayed fishes and the availability of soft-rayed prey cound determine the degree of predation on other species.
Generally, there a few definitive studies to quantify impacts (if any) of Muskellunge on other fish species. There is very little evidence to indicate that Muskellunge have a significant negative impact on populations of other popular sport fish species including Walleye, Largemouth Bass and Smallmouth Bass. In fact, there are numerous instances where these fish species successfully co-habit the same waterbody. Since Muskellunge seldom occupy coldwater habitats, their interactions with coldwater fishes (i.e. salmonids and coregonids) are poorly understood. This is an area which requires future study.
Potential negative impacts of Muskellunge on other fish species are probably related to the size of waterbody and the composition of the resident fish community. Larger waterbodies and those waters having a diverse forage fish community seem to be relatively unaffected by the presence of Muskellunge. The presence/abundance of soft-rayed fish species likely reduces the predation on other resident fish species.
Other fish species can have negative impacts on the Muskellunge. Northern Pike are known to have a competitive advantage over Muskellunge where they coexist. Young Muskellunge are also subject to predation by other fishes including Largemouth Bass, Yellow Perch, Rock Bass and Walleye.
Based on this literature review several recommendations are offered. These are related to initiating more quantified studies to document impacts (if any) when Muskellunge are introduced or become established in new waters, utilizing new state-of-the-art techniques to determine diets and predatory-prey relationships amongst a broader range of fish community types (including salmonids and species at risk), and developing efforts to improve the public perception of Muskellunge.
The full report is available by clicking the link below.
