WATER SEDIMENTS SHORELINES BIOLOGICAL RESOURCES USES

2nd edition ST. LAWRENCE FRESHWATER FISH COMMUNITIES

Background Figure 1. St. Lawrence Fish Monitoring Network: Sampling years and site map for the first two sampling campaigns (1995–97 and 2001–2006) hile the initial impression of the The third campaign is under way. WSt. Lawrence River is one of strength and stability, this highly 1995, 1997, dynamic environment is in fact 2002, 2003, 2007 1997, 2006 Lake Saint-Pierre Grondines– constantly changing. This is why it and archipelago Saint-Nicolas must be closely monitored. Fish are 1997, 2005 Grondines Batiscan Lake Saint-Louis Trois-Rivières Donnacona excellent indicators of the health of the Québec City Berthierville Gentilly St. Lawrence, not only because they Lanoraie Bécancour Saint-Nicolas Sorel integrate spatial and temporal changes Coteau- Laval in the physical environment, but also Landing Cornwall Montréal Boucherville Bécancour– because they are sensitive to most Longueuil Batiscan environmental pressures and stresses. Beauhamois Montréal–Sorel 1996, 2001, 2008 Fish are easy to sample, useful for Lake Saint-François 2001

1996, 2004 0 25 50 km measuring the effects of toxic UNITED STATES substances, and of interest to decision- makers and the general public because on fish communities and the popula- cycle (2001–2006). The study areas of their great heritage value and socio- tion dynamics of several fish species stretch from the Quebec–Ontario economic importance. of interest. The goal is to assess the border, upstream, to Quebec City, Since 1995, the St. Lawrence Fish health of the Quebec portion of the downstream. The portion between Monitoring Network (FMN) has been freshwater St. Lawrence. Sectors Montréal and Sorel was added to using a standardized and reproducible fished during the 1995–97 campaign the second sampling campaign method to collect quantitative data were sampled again during the second (Figure 1). BIOLOGICALBIOLOGICAL RESOURCES

Many concrete actions have been taken to better protect and manage the wildlife, plants and habitats of the St. Lawrence and reduce the sources of contamination (see http://www.planstlaurent.qc.ca/sl_obs/ sesl/publications/fiches_indicateurs/ fiches_e.html). However, the signs of an unbalanced ecosystem continue to abound and are, in many ways, symp- tomatic of the river’s fragile health. Today, the river, which is already sub- ject to several natural and anthro- pogenic pressures, is faced with new stresses whose effects are poorly Photo: Yves Mailhot, ministère des Ressources naturelles et de la Faune understood, if at all. Specifically, a number of emergent contaminants are Overview of the variety of aquatic habitats in the Nicolet area: from left to right, large grass beds, contrasting water masses, and deeper water. being found (and going untreated) in wastewater, including some that have estrogenic (feminizing) effects on the river’s aquatic biota. Other threats to the ecological integrity of the St. Lawrence are: invasive species; Free movement of fish climate change, which modifies the The St. Lawrence fish communities include a great number of migratory river’s flow and water temperature; and species, and habitat fragmentation could have extremely negative effects on the interactions among these new their development. In natural situations, fish frequent many and varied crit- ical habitats during their various life stages, habitats that may be very far pressures (e.g. rising temperatures apart, such that the connections among these different habitats must be could facilitate the spread of invasive maintained to prevent the local extinction of some populations. species). The FMN contributes to The free movement of fish is important all along the St. Lawrence and measuring these effects on the aquatic between the river and its tributaries, no matter their size. Observations of environment over time and space by Lake Sturgeon, American Shad, Walleye, Atlantic Tomcod, Yellow Perch and providing the decision-support data Copper Redhorse, for example, further illustrate the important role the necessary to minimize the stresses on tributaries play in river-tributary dynamics, specifically in reproduction, as the ecosystem. well as the importance of good water quality in the tributaries. Furthermore, fish often derive thermal benefits from frequenting smaller bodies of water that heat up faster, which has positive effects on the maturation of adults, Overview of the Situation the growth of the young and their food supply. Sometimes, construction of fish ladders of various designs and sizes, like A Heterogeneous Environment those that exist for the American Eel on the St. Lawrence and for other The St. Lawrence River is a complex species on the Richelieu River and the Rivière aux Pins or the Ruisseau de ecosystem, comprised of fluvial lakes Feu, may partially reduce the impacts of habitat fragmentation, without and narrow reaches with physio- compensating for it. graphic and hydrological characteris- tics that are highly variable over space and time. This natural heterogeneity greatly influences the river’s habitats

State of the St. Lawrence River St. Lawrence Freshwater Fish Communities BIOLOGICALBIOLOGICAL RRESOURCESESOURCES

and fish communities, which vary with the diversity of available aquatic also by the tide (downstream from the very different flow patterns of habitats, and the introduction, over Trois-Rivières), shelter smaller areas of calm-water and fast-flowing areas. In more than a century, of non-native aquatic plant communities having a addition, many tributary rivers and species like carp, Tench and Round lower diversity of fish compared to the effluents discharge into the St. Goby. fluvial lakes. Lawrence, carrying with them their dis- Lake Saint-Louis and Lake Saint- tinctive natural physical and chemical Biotic Integrity Index Pierre and its archipelago are by far the Although the available fis h habitat characteristics, including some that richest in terms of species numbers has remained fundamentally unchanged are highly degraded compared to the and abundance—characteristics that since the overall assessment was pub- river. In fact, over a large part of its can be associated with the free move- lished in 2003, several findings remain course, the river appears as the juxta- ment of fish, the large areas of avail- harsh and worrisome. Compared to positioning of several rivers flowing able habitat and the varied physical 1995–97, most biotic integrity index side by side, each with its own “signa- conditions in these sections of the (BII) values, developed to assess the ture” that can be identified over a great river. On the other hand, the potential health of the river’s living communi- distance: these we refer to as “water of Lake Saint-François for use by fish ties, have remained within the limits masses.” Moreover, the river is artifi- seems to be greatly diminished by considered low or average (Figure 4). cially split in two by a ship channel the dams that isolate it from the that restricts the flow between the St. Lawrence system, cutting off access The BII comprises 12 descriptors north and south banks, further concen- to migratory species, causing local combining species diversity, species trating water flow to the centre. This losses of riparian and whitewater abundance based on certain trophic natural physical heterogeneity, along habitats, and creating highly stable levels (insectivore, omnivore, pisci- with many small-and large-scale water levels. Freshwater reaches, vore), the contribution of tolerant and anthropogenic disturbances, is the which are narrower and influenced by intolerant species to some types of pol- reason for the wide contrasts among faster currents (Montréal–Sorel) and lution, and the prevalence of external the fish communities of the different sections of the river. Figure 2. Upstream-downstream trends in fish community diversity in the St. Lawrence Diversified Fish Communities Lake Saint-Louis and Lake Saint-Pierre and its archipelago have the richest species diversity. The experimental fisheries conduct- 40 ed under the FMN for the sampling periods 1995–97 and 2001–2006 35 confirmed the tremendous diversity of 30 St. Lawrence River fish communities (Figure 2). Overall, nearly one hundred 25 freshwater and diadromous species are distributed throughout the river 20 based on physical conditions and 15

habitat preferences (Figure 3). This Numb e r of s p e cies diversity is the result of the large 10 geographic extent of the river, its 5 position between the Great Lakes and the Atlantic Ocean, its connections 0 215 464 221 226 232 237 274 280 383 388 392 396 401 406 411 416 421 427 459 468 473 494 512 518 322 327 333 338 343 348 353 358 363 368 with southern river systems such as 267 500 506 Lake Lake Montréal–Sorel Lake Lake Gentilly– Grondines– the Mississippi via Lake Michigan and Saint- Saint- Saint-Pierre Saint-Pierre Batiscan Donnacona the Hudson River via Lake Champlain, François Louis archipelago

StateoftheSt.LawrenceRiver St.LawrenceFreshwaterFishCommunities BIOLOGICAL RESOURCES

Figure 3. Average abundance of three dominant St. Lawrence River species abnormalities (deformities, erosions, From Lake Saint-François to Bécancour–Batiscan, the Yellow Perch is the most lesions, tumours). Several of these vari- abundant species sampled under the FMN. It is highly prized by fishers. Despite its great fecundity, it is in trouble in Lake Saint-Pierre. The Sauger, very sensitive to light, ables are influenced, to varying has disappeared from Lake Saint-François, but is progressively abundant from degrees, by both natural and anthro- upstream towards downstream. This predator could play an important role in control- ling invasive species such as the Round Goby. Spottail Shiner, an abundant, ubiquitous pogenic changes observed in the living and sedentary forage fish, is used as a sentinel species to track the local effects environment of the fish. Therefore, of several contaminants, including mercury, and endocrine disruption in the Great Lakes–St. Lawrence system. healthy sections of the St. Lawrence contain a high number of indigenous 5 species, several of which are intolerant a. Yellow Perch (Perca flavescens) to pollution and have a low prevalence 4 of external abnormalities. Due to the absence of data time-series of suffi- 3 cient length, and without accurate historic references, BII values consid- 2 ered “excellent” represent the river’s health at its potential best. 1 The BII developed for the St. Lawrence is a sensitive tool for identi- 0 fying the overall, cumulative effects of habitat disruption and of certain b. Sauger (Sander canadensis) pollution sources. It can be used to 2 determine the quality of the aquatic environment based on the level of integrity of the communities inhabit- ing it. A preliminary report from the 1 FMN’s second sampling cycle shows Abundance clearly that there is still significant room for improvement of the aquatic environment. Some river sections have

0 gotten better, some have gotten worse, 4 and some cases point to the success of c. Spottail Shiner (Notropis hudsonius) management plans to enhance the health of certain fish populations by 3 reducing fishing and rehabilitating critical habitats.

2 The BII was not the sole indicator examined to assess the health of St. Lawrence fish. Highly informative data 1 from the FMN have also been used to calculate the parameters of the popu- lation dynamics of several fish species: 0 the results are presented below. 215 221 226 232 237 267 274 280 322 327 333 338 343 348 353 358 363 368 383 388 392 396 401 406 411 416 421 427 459 464 468 473 494 500 506 512 518 Lake Lake Montréal–Sorel Lake Lake Gentilly– Grondines– Saint- Saint- Saint-Pierre Saint-Pierre Batiscan Donnacona François Louis archipelago

State of the St. Lawrence River St. Lawrence Freshwater Fish Communities BIOLOGICAL RESOURCES

Figure 4. Upstream-downstream trends in the BII along the north and conducive to the growth and matura- south shores for 1995–97 and 2001–2006 tion of these fish. The maintenance of Each sequence of points corresponds to a river section. The south shore of the Lake populations is entirely dependent on Saint-Pierre islands could not be sampled due to the strength of the current and the proximity of the ship channel. Most BII values during the two sampling periods were the ability of the different life stages within the range considered low or average (BII classes: 1–24: very low; 25–36: low; moving freely among critical habitats— 37–47: average; 48–56: good; 57–60: excellent). habitats that are spread out over the a. North shore entire river. This is the case of both the 60 Excellent Atlantic Sturgeon and the Lake Period 1 (1995–1997) Good 50 Period 2 (2001–2006) Sturgeon, whose future was still in

Ottawa doubt less than a decade ago. Today, Average River thanks to careful planning and major 40 initiatives to protect and enhance their habitats, both species support sus- 30 Low tainable fisheries in the fresh and Portneuf River brackish waters of the St. Lawrence. 20 Stocks of American Shad, another

Very low migratory species, return to the river to 10 spawn each spring from the Bay of Fundy, with some travelling as far as 0 upstream of Montréal. Reintroduction

b. South shore of the Striped Bass also seems to be 60 Excellent progressing well: fish caught after the Saint-Louis Period 1 (1995–1997) Good River river was stocked indicate that habi- Period 2 (2001–2006) 50 tats are of good quality, since there Biotic Integrity Index (BII) has been survival, growth and disper- Average 40 sion of the species over a wide area. Low Other migratory species, however, are 30 more vulnerable: the recruitment of American Eel, historically important to

Gentilly-2 20 discharge channel the fluvial food web as well as being of economic value, fell two orders of Very low 10 magnitude in less than 25 years. On a smaller scale, the Rainbow Smelt pop- ulation of the south shore of the estu- 0 464 215 221 226 232 237 274 280 383 388 392 396 401 406 411 416 421 427 459 468 473 494 512 518 267 500 506 ary remains small, despite efforts

Lake Lake Lake Lake Gentilly– Grondines– invested toward its recovery. Saint- Saint- Saint-Pierre Saint-Pierre Batiscan Donnacona François Louis archipelago The picture also varies for the typi- cal freshwater species. Cut off from Fish Communities Destabilized whitewater following the construction migratory routes and subject to condi- by Numerous Pressures of dams at either end of Lake Saint- tions of increased water transparency François. However, the portion of the with the introduction of the Zebra The upstream portion of the fluvial river running nearly 350 km between Mussel into the ecosystem, Sauger section is still subject to the effects of Lake Saint-Louis and the freshwater have disappeared from Lake Saint- environmental fragmentation and sta- limits still allows the free movement of François. Walleye in this lake are vul- bilization and the loss of vast areas of migratory species and offers conditions nerable for the same reasons, though

State of the St. Lawrence River St. Lawrence Freshwater Fish Communities h nagrdCpe ehre pce htol xssi otwsenQuebec. southwestern in exists only that species a Redhorse, Copper endangered The Lawrence. St. the of tributary a River, Ouareau the on spawn Sturgeon Lake s e i t i n u m m o C h s i F r e t a w h s e r F e c n e r w a L . t S r e v i R e c n e r w a L . t S e h t f o e t a t S ILGCLRESOURCES BIOLOGICAL

Photo: Daniel Hatin, ministère des Ressources naturelles et de la Faune Photo: Yves Chagnon, ministère des Ressources naturelles et de la Faune Pickerel) are also protected under under protected Act. ’sRisk At Species also are Pickerel) Grass and Darter Sand Darter,Eastern River Redhorse, Bridle Shiner, Channel and Redhorse (Copper species these law.Quebec of under Six vulnerable or threatened as designated be to likely species 14 and estuary), southern the Shad, in Smelt Rainbow (American and Darter Channel species nerable endangered one vul- three Redhorse), (Copper are species today River Lawrence St. the of part Quebec the in present fish the Among years. ten past the of efforts restoration and tection pro- the of maintenance medium-term the on depends survival Its species. endangered an Redhorse, Copper of is home to the world’s only population River Lawrence St. The place. in rently cur- measures protective the despite term medium the in reversed be only Lake in Saint-Pierre, however and, at best, may continued has population YellowPerch the of decline The Pierre. Saint- Lake in specifically river, the in healthy remain populations but tats, habi- its of degradation to due taries tribu- the in vulnerable very is Shiner Bridle The areas. other in well faring shoreline habitats,environmental such their Besides effects on the dynamics of riparian and carp. especially for are decimating which 2001, in seen abnor- mally high temperatures such as those with associated die-offs fish and earlier periods, low-water or lower lower floods, of things, probability other water the among river’s with, the regime, of modification major to lead may way under changes ecosystem, the with still unknown effects. The climatic on bear to brought New ye o pesrs r being are pressures of types BIOLOGICALRESOURCES

Table 1. Partial list of pressures and disturbances on St. Lawrence fish outreach is international in scope. The and their habitats since the early twentieth century knowledge acquired under the network Protection and conservation efforts must be adapted to new realities. has already contributed toward the production of more than 50 reports, Pressures Effects on fish scientific papers and brochures, and Dams, hydraulic and hydro- Habitat fragmentation, barriers impeding fish 40 far-reaching oral communications. electric works, flow regulation migration, direct mortality or serious injury during downstream migration, water-level stabilization, It has been widely used in impact loss of habitat, modified flow studies, legal assessments (fish Waterways and dredging Habitat fragmentation, limited movement between habitat) and wildlife notices (legal banks, habitat loss at sediment deposition sites, authorizations, consultations, restora- increased turbidity tion projects, etc.) in the adjoining Flow regulation Water-level stabilization modifying plant succession, areas of the river. By availing itself of habitat loss, restricting of floods services such as those of the FMN, the Various types of pollution Degraded water quality, habitat loss, fish die-offs Government of Quebec is respecting Various types of contamination Acute or chronic diseases, mortality, reduced the commitments it made in 1992 in immunity Rio de Janeiro and in 2002 in Overfishing Direct mortality and decreased fishery production Johannesburg to preserve biodiversity. Bank erosion Habitat loss, increased turbidity The basic sampling data contained Encroachment, filling, etc. Habitat loss, modified flow in the FMN are invaluable. They are Climate: more frequent Habitat loss, mortality, lower immunity, modified being used in myriad ways to extremes, lower water levels, recruitment and fishery production, modified flow, enlighten managers and contribute to modified flood signals new biogeographical distribution research on the St. Lawrence ecosys- Numerous invasive and Modified ecosystem and trophic network functions, plant species: Zebra Mussel, habitat disruption, competition with indigenous tem: fish health, impact of river flow Chinese Mitten Crab, species, positive effect of addition of forage fish regulation, management of fisheries Round Goby, Tench, stocks, monitoring Striped Bass Common Reed, etc. reintroduction, status of rare or threat- New diseases Acute or chronic diseases, mortality, modified ened species, contamination of fish ecosystem functions tissue, monitoring the spread of inva- Partially-treated wastewater Endocrine disruption: feminization of male fish, sive species, feminization by estro- containing many emergent reproductive failure genic or related substances, etc. The pollutants Bromine: little-known effects, possibly comparable to chlorine compounds FMN has been so successful that it is being extended to cover the upper estuary of the St. Lawrence. Planning for this initiative began in 2006. conditions make the task of reconcil- transfer routes in the food web, as well ing the protection of biodiversity and as nutrients, contaminants and The choice of BII metrics will be the maintenance or development of pathogens in the aquatic ecosystem. fully reviewed and new ones devel- shipping on the river even more com- oped in order to adapt the BII to plex. Inputs of nutrients via tributaries Outlook the new realities of the St. Lawrence located in farming areas may also (global warming, invasive species, etc). aggravate the harmful effects on the The Fish Monitoring Network (FMN) BII values will also be associated with quality of the aquatic environment. was formed in 1995 as part of the all the known sources of stress on the The Round Goby’s rapid colonization St. Lawrence Action Plan. This unique ecosystem, including the contami- of the river is likely to modify, in a cur- initiative has had many positive scien- nants contained in the wastewater rently unforeseeable manner, energy tific and political benefits, and its discharged by the City of Montréal.

StateoftheSt.LawrenceRiver St.LawrenceFreshwaterFishCommunities Aussi disponibleenfrançaissousletitre : Lescommunautésdepoissonsd’eaudoucedansleSaint-Laurent Legal deposit–NationalLibraryofCanada, 2008 Envirodoq: ENV/2002/0343A ISBN 0-662-33249-0 Catalogue No.En4-14/2002E © GouvernementduQuébec,2002,2nd edition 2008 de l’EnvironnementetdesParcsduQuébec Published byAuthorityoftheMinistreduDéveloppementdurable, © HerMajestytheQueeninRightofCanada,2002,2ndedition2008 Published byAuthorityoftheMinisterEnvironment U Québec, du Faune la de et relles natu- R esourc des Minstère t he Québec, Cand, O ceans and du Fisher Parcs des et ment l’Enviroe- d e durable, pemnt Canada, theMinistèreduDévlop- partnes—Eviom governmt for aSustinbleDvpm,x Plan L awrenc St. the agremnt, • • aqutic eosymb: provide nfmathl descripto comunity and poulatin fish Al nder thcuCa–Qéb biotc integry dxoBI. a calute to posible it makes this them; among abnormlites f o types various the a nd polutin to ensitv s s pecis of ber fish comunites hab,dvry- f o charteis main the measuring suply arekmtobnid; ductive s,rmngowhaf r epro- are, habit avilbe demographics; ed tohvariuslfg,n charteizng fspouldym- KEY MEASURES State s e i t i n u m m o C h s i F r e t a w h s e r F e c n e r w a L . t S of the r e v i R e c n e r w a L . t S e h t f o e t a t S St. LawrenceMonitoringProgram regular intervals. at River Lawrence St. the of state Canadians withinformationonthe pooling theirexpertisetoprovide are comunites, rivesd with ctively a w orks tha no-gvermtal organizt a gency— A aint- S Laurent, Straégies Cand with togehr Parks the and Agency, Space Canadian the pour lefleuveSaint-Laurent, biotique d’intégrité indice d’un développement et poissons Y. MAILHOT2003.Caractérisationdescommunautésde and LA VIOLETTE,N.,D.FOURNIER,P.DUMONT, faune Mauricie-Centre-du-Québec–May2006. la de l’aménagement de Direction la – de Montérégie and Laval Montréal, de faune la de ment recherche surlafaune–Directiondel’aménage- Monitoring Network(1994–2006).Directiondela Fish Lawrence St. the from data from produced List ofdocumentsandresearchcommunications la de Direction recherche surlafaune.237pp. Québec, du parcs des et faune Ministère desRessourcesnaturellesetdelaFaune Secteur Faune, Chantal CôtéandNathalieLaViolette Yves Mailhot,PhilippeBrodeur,DeniseDeschamps, Marc Mingelbier,YorickReyjol,PierreDumont, Prepared by: R ESOURC BIOLGCA at: Progam, plesvituWb Stae ofh.LwrncMig the about information additional To KnowMore and sheets fact the obtain To w.planstureqc 1995-1997. 1995-1997. Société dela

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