Bay Of Quinte Research Articles

Nearshore fish community assessment on Lake Ontario and the St. Lawrence River: A trap net-based index of biotic integrity

Abstract An index of biotic integrity (IBI) based on an Ontario provincial standard nearshore community index netting (NSCIN) protocol was developed to assess nearshore fish communities and ecosystem health in the Lake Ontario/St. Lawrence River ecoregion. The IBI was based on 11 individual metrics representing aspects of fish assemblage integrity: taxonomic richness, habitat guilds, trophic guilds, and overall abundance and biomass. Thirteen geographic areas were sampled and grouped into three habitat types: sheltered embayments, exposed embayments, and riverine. IBI values were higher for sheltered embayments (mean IBI = 71, excluding Hamilton Harbour) than for exposed embayments (62, excluding Toronto Harbour) and riverine areas (64). The IBI accurately reflected anticipated contemporary differences in ecosystem health among geographic areas as well as historical changes within the Bay of Quinte. Two designated areas of concern (AOCs) where remedial action plans (RAP) are ongoing, Hamilton Harbour, a sheltered embayment, and Toronto Harbour, a more exposed area, had lowest IBI values (45 and 47, respectively). IBI values on Bay of Quinte and Lake St. Francis AOCs, where RAPs are nearing completion, were very similar to IBI values from less affected embayments and nearshore areas within their respective habitat types. Upper and middle Bay of Quinte IBIs increased from 47.3 and 45.9, respectively, to 71.8 and 69.2 over a 45-year time period (1969–2013) consistent with previously documented major ecosystem change.

Delineation of the role of nutrient variability and dreissenids (Mollusca, Bivalvia) on phytoplankton dynamics in the Bay of Quinte, Ontario, Canada

The Bay of Quinte, a Z-shaped embayment at the northeastern end of Lake Ontario, has a long history of eutrophication problems primarily manifested as spatially extensive algal blooms and predominance of toxic cyanobacteria. The purpose of this study was to identify the structural changes of the phytoplankton community induced by two environmental alterations: point-source phosphorus (P) loading reduction in the late 1970s and establishment of dreissenid mussels in the mid-1990s. A combination of statistical techniques was used to draw inference about compositional shifts of the phytoplankton assemblage, the consistency of the seasonal succession patterns along with the mechanisms underlying the algal biovolume variability in the Bay of Quinte over the past three decades. Based on a number of diversity and similarity indices, the algal assemblages in the upper and middle segments of the Bay are distinctly different from those typically residing in the outer segments. Our analysis also identified significant differences among the phytoplankton communities, representing the pre- and post-P control as well as the pre- and post-dreissenid invasion periods. Recent shifts in phytoplankton community composition were mainly associated with increased frequency of occurrence of toxin-producing Microcystis outbreaks and reduced biovolume of N2 fixers, such as Aphanizomenon and Anabaena. Bayesian hierarchical models were developed to elucidate the importance of different abiotic factors (light attenuation, water temperature, phosphorus, and ammonium) on total cyanobacteria, Microcystis, Aphanizomenon, and Anabaena relative biovolume. Our modelling exercise suggests that there is significant spatial heterogeneity with respect to the role of the factors examined, and thus total phosphorus alone cannot always explain the year-to-year variability of cyanobacteria succession patterns in the system. The lessons learned from the present analysis will be helpful to the water quality criteria setting process and could influence the management decisions in order to delist the system as an Area of Concern.

The ecological history of Lake Ontario according to phytoplankton

Abstract Lake Ontario's condition has fluctuated since European settlement, and our understanding of the linkages between observed ecosystem shifts and stressors is improving. Changes in the physical and chemical environment of the lake due to non-indigenous species, pollution, sedimentation, turbidity, and climate change altered the pelagic primary producers, so algal assessments have been valuable for tracking long-term conditions. We present a chronological account of algal assessments to summarize past and present environmental conditions in Lake Ontario. This review particularly focuses on pelagic, diatom-based assessments as their fossils in sediments have revealed the combined effects of environmental insults and recovery. This review recaps the long-term trends according to three unique regions: Hamilton Harbour, the main lake basin, and the Bay of Quinte. We summarize pre-European impact settlement; eutrophication throughout most of the 20th century; subsequent water quality changes due to nutrient reductions; and filter-feeding dreissenid colonization and contemporary pelagic, shoreline, and embayment impairments. Recent data suggest that although phytoplankton biovolume is stable, species composition has shifted to an increase in densities of spring eutrophic diatoms and summer cyanobacteria. Continued monitoring and evaluation of historical data will assist in understanding and responding to the natural and anthropogenic drivers of Lake Ontario's environmental conditions.

Nearshore habitat associations of stocked American eel, Anguilla rostrata, in Lake Ontario and the upper St. Lawrence River

Abstract Approximately 3.9 million glass and elver stage American eels ( Anguilla rostrata ), life stages never before represented in Lake Ontario, were stocked into two locations, the upper St. Lawrence River and the Bay of Quinte, to help recover a segment of the panmictic population under severe decline. We characterized near-shore patterns of abundance and size and indicated habitat associations in the two stocking locations. Generalized additive models identified that in spring, eel presence was positively associated with the percentage of soft (organic or silt) substrate, and negatively associated with gravel substrate. In the fall, eel presence was positively associated with rubble substrate. Canonical correspondence analysis demonstrated eel habitat preferences that change as eels grow, and that these preferences do not vary with season. Small eels ( 1 m). These habitat shifts are likely due to a combination of physical space requirements, habitat availability and prey preference changing with increasing body size. The availability of suitable habitats differed between main stocking locations, yet neither location had an ideal mix of coarse substrates (for smaller eels) and fine substrates (for larger eels). The observed habitat shifts resulted in the stocked American eels utilizing an array of habitats, fitting the general view of the species as a habitat generalist, but it is apparent that in the Great Lakes eels use specific substrate features that change with increasing length.

A model of the three-dimensional hydrodynamics, transport and flushing in the Bay of Quinte

Abstract The Bay of Quinte, Ontario, receives excessive nutrient loads and suffers from poor water quality. The 70 km long z-shaped bay traps the nutrients due to limited flushing with Lake Ontario, leading to increased nutrient residence times. Therefore, it is important to understand the three-dimensional hydrodynamic conditions within the bay, as these drive horizontal transport, dilution of nutrient rich inflows and water exchange to the lake. In this study, the effects of meteorological forcing, river inflows and Lake Ontario exchange on the hydrodynamics and mixing were investigated using a numerical model. The model was validated against temperature time series and profile data, with a maximum root-mean-square deviation

The Laurentian Great Lakes in transition: A chronicle of research at the base of the foodweb

A unique science and management strategy has been developed for the Laurentian Great Lakes due to their enormous size, geographic-ecological diversity, political and economic importance. This article is a documentary of more than 40 years of research conducted at the base of the foodweb by Fisheries and Oceans Canada, which has contributed significantly to the management of the Great Lakes. In the 1960s, the governments of Canada and the United States responded to the threat of cultural eutrophication which eventually resulted in the signing of the binational Great Lakes Water Quality Agreement. Dr. R. A. Vollenweider and Dr. J. R. Vallentyne were instrumental in developing a phosphorus abatement program, as well as the adoption of the “ecosystem approach” resulting in an holistic and integrated protocol for managing multiple environmental stressors. By showcasing some selected examples (Lake Ontario, Bay of Quinte, current research activities), an attempt is made to chronicle the evolution of phytoplankton, primary productivity and microbial foodweb research in the Great Lakes. Some of the research programs, techniques, models, policies and international cooperation are highlighted, in addition to the strong European influences on Great Lakes research. The lessons learned from the long-term Great Lakes research experience could be extrapolated and applied to enhance understanding of the ecology and management of other large lake ecosystems throughout the world.

Management of Great Lakes fisheries: Progressions and lessons

Fishery resources include the fishes, the other biota they interact with, and the habitats they occupy. The historical sequences in the use and management of these resources may be considered as a series of interacting sequences of change. These sequences can span from social, economic, institutional and landscape changes, through water quality, habitat supply, and climate changes, to biotic composition changes, introductions and extinctions, and species harvest changes. A selection of these sequences is examined for the St. Lawrence-Great Lakes which has been subjected to intense development and study over the last 200 years. While the whole basin is considered, some detailed attention is given to Lake Ontario and, within it, the Bay of Quinte. Brief selective development histories are given for the three areas as context. The management history is outlined and critiqued. While much progress has been achieved in cleaning up the load-driven problems in the basin, little secure progress toward rehabilitation and sustainability has been achieved. In the current period of economic problems, governments, particularly Canada’s, are undoing past ecosystem management progress. The development of St. Lawrence-Great Lakes’ ecosystem science has drawn heavily from both oceanography and limnology. A brief, selective overview of several progressions in ecosystem science illustrates how knowledge and understanding of this ecosystem has expanded over the last 60 years, providing an improved basis for management action. As with use and management, the science of fishery resource management has consisted of many historical progressions. The many sequences in the St. Lawrence-Great Lakes management and science histories lend support for recognition of (i) the importance of taking an ecosystem approach to renewable resource management, (ii) the value of adaptive management practices and, particularly, (iii) the vital complementary roles of long-term monitoring and mathematical modelling.

Comparison of ovum lipid provisioning among lake whitefish, walleye and northern pike co-habiting in Bay of Quinte (Lake Ontario, Canada)

We compared size, total lipid contents, percent of lipids as neutral lipids and fatty acid profiles of ova from Bay of Quinte (Lake Ontario) populations of lake whitefish and northern pike to previously reported data from Bay of Quinte walleye. We also assessed how the relationships between ovum lipid fatty acid composition and maternal size or age varied among these species. Ovum size, total lipid content and percent neutral lipid differed among the three species and in general were not influenced by maternal size or age. The highest percentage of neutral lipid occurred in walleye ova and the lowest in northern pike. Principal components analysis revealed significant separation of fatty acid profiles among the three species, with greater differences in the neutral lipids than in the polar lipids. Lake whitefish were more distinct from the walleye and northern pike than the walleye and northern pike were from each other in the neutral lipids. Lake whitefish ova had higher percentages of eicosapentaenoic acid (EPA) in both lipid fractions than those of the other two species. In direct contrast to the previously observed trends in walleye, percentages of arachidonic acid and docosahexaenoic acid decreased while those of EPA increased with maternal size in the lake whitefish. None of the major fatty acids in northern pike ova varied significantly with maternal size or age. Our study reveals that the Bay of Quinte populations of the three species have different patterns of allocation of fatty acids to ova as they grow and age.

A modeling assessment of contaminant fate in the Bay of Quinte, Lake Ontario: Part 2. Organic chemicals

A mass balance model of contaminant fate-transport was applied to 11 organic compounds in the Bay of Quinte and its foodweb. Total loadings were back-calculated from measured concentrations in sediment and/or fish for most chemicals due to limited measured concentrations in the contributing tributaries and point sources such as STPs. Total loadings decreased between 1988 and 2000 from 1–2 orders of magnitude for TCDD/F to 30% B[a]P and 80% for ΣPCBs. Total loadings in 2000 ranged from 10 mg day−1 for TCDD/TCDF to ∼0.01–0.5 kg year−1 for mirex, p,p′-DDT and BDE-47, to ∼1 kg year−1 for dieldrin and HCB, ∼10–50 kg year−1 for ΣPCB and B[a]P, and 2000 kg year−1 for atrazine. Despite concentration reductions, sport fish exceeded the lowest Ontario fish consumption guidelines for ΣPCB, TCDD and TCDF. Model results suggested that atmospheric deposition was the main source of lower molecular weight PCBs, TCDD/F and DDT, tributaries for higher molecular weight PCBs, and Lake Ontario for mirex, atrazine and dieldrin loadings. The main source of B[a]P was thought to be urban runoff, unknown for long-banned HCB and sewage treatment plants for 17β-estradiol. Results for BDE-47 were illustrative due to the lack of data. Industrial sources did not contribute to overall sediment or fish concentrations (not including “hot spots”). Organic compounds in the Bay were estimated to have a short residence time of days in the water column due to rapid export to Lake Ontario, except for HCB and 17β-estradiol which were estimated to be lost by volatilization and transformation, respectively. The response time of organic compounds in sediment varied from <1 year (atrazine) to ∼50 years (ΣPCB).

Wild fish from the Bay of Quinte Area of Concern contain elevated tissue concentrations of PCBs and exhibit evidence of endocrine-related health effects

The Bay of Quinte (BOQ) is an Area of Concern listed under the Great Lakes Water Quality Agreement. The presence of dioxins and dioxin-like PCBs in fish in the BOQ AOC has led to restrictions on fish consumption by humans, which is a beneficial use impairment. Adult yellow perch (Perca flavescens) and brown bullhead (Ameiurus nebulosus) were sampled from Trenton, Belleville, and Deseronto (reference site) in the BOQ. A suite of hormone assays and various measures of exposure and/or sublethal health effects were used to assess the health status of fish of both species and sex. Condition factor, hepatosomatic index, ethoxyresorufin-O-deethylase activity, circulating steroid and thyroid hormones, thyroid activation, oocyte size distribution, spermatogenic cell stages, and plasma vitellogenin were among the endpoints that were significantly (p<0.05) affected by location. Many of those effects corresponded with significantly (p<0.05) greater tissue concentrations of polychlorinated biphenyls (PCBs) at Belleville and Trenton. Hepatic extracts from brown bullhead sampled from Trenton had significantly (p<0.05) greater binding activity to the androgen receptor and sex steroid binding protein. Taken together, these data and preliminary data from a concomitant study suggest that PCBs are likely being hydroxylated in vivo, resulting in enhanced bioactivity at endocrine receptors and measurable health responses. The present study supports the growing body of evidence that PCBs and their metabolites can affect fish thyroid and steroid hormone systems.

Complex seasonality observed amongst diverse phytoplankton viruses in the Bay of Quinte, an embayment of Lake Ontario

Summary To initiate research on algal viruses (viruses that infect eukaryotic algae) and cyanophages (viruses that infect cyanobacteria) in the Bay of Quinte, a Lake Ontario embayment, samples of viruses free in the water (i.e. not associated with particulate material) were collected throughout 2011 with the goals of examining the diversity of phytoplankton viruses and monitoring their dynamics. PCR and sequencing of DNA polymerase (polB) and major capsid protein (MCP) genes from algal viruses, and sheath protein genes from cyanophages, revealed diverse phytoplankton viruses in the bay. Specifically, polB sequences from the bay were most closely related to sequences from viruses that infect prasinophyte algae, MCP sequences were related to sequences from viruses that infect prasinophytes and from Mimivirus‐like viruses that infect prymnesiophytes and prasinophytes, whilst sheath protein sequences were related to sequences from the phage Ma‐LMM01 that infects M. aeruginosa. The abundances of 10 distinct viral genes monitored using quantitative PCR ranged from exceptionally high values (e.g. 256 441 gene copies mL−1 for a putative M. aeruginosa phage) to values that were just above detection limits (e.g. a putative Prasinovirus never exceeded 20 gene copies mL−1). Patterns of abundance included genes that were seasonally sporadic or geographically patchy, as well as some that were stable throughout the bay over the entire year. Despite the heterogeneity of viral abundance across the bay, gene abundance clustered by sampling date and geographical location. Even for closely related viruses, seasonality and geographical distribution were distinct. By providing evidence for the complex seasonality of diverse phytoplankton viruses, this work highlighted significant gaps in knowledge of aquatic virus ecology that can be extrapolated from this one system to most aquatic environments.

The science of ecosystem-based management on a global scale: The Laurentian Great Lakes, Lake Ontario, and the Bay of Quinte as a nested case study

Lake ecosystems are our sentinels of environmental change and their effective management is one of our key planetary challenges in the 21st century. The evolution of ecosystem science as a basis for management is reviewed using the nested set of the Laurentian Great Lakes, Lake Ontario, and the Bay of Quinte as a primary focus. Other great lakes of the world, many of which are in Canada, provide a secondary focus. Ecosystem science has a long history in the Laurentian Great Lakes with developments driven in large part by the Great Lakes Water Quality Agreement, Lake-Wide Management Plans, and Remedial Action Plans for Areas of Concern. By comparison most other large Canadian lakes have received little attention as is the case with many of the world's great lakes. The substantial arsenal of tools and knowledge accumulated in the Great Lakes can serve as a model for other lake systems. As the range of ecosystem management problems has continued to grow, the motivating theme has shifted from restoration through rehabilitation to adaptation. The main challenge is to coalesce the many stresses we previously have sought to manage singly: land use, population growth, habitat degradation, resource exploitation, invasive species, pollutant and contaminant loadings, and, finally, climate change. Essential features of effective ecosystem-based management are: a whole system view, active adaptive management, acceptance of science-based evidence, and shared goals with common objectives. The last two may prove the greatest hurdle as society becomes ever more divided and fractious given the global onslaught of environmental and societal challenges. The Great Lakes experience shows there is hope.

A tribute to the Aquatic Ecosystem Health and Management Society and its founder, Mohi Munawar

Aquatic ecology received a boost globally in 1989 with the establishment of the Aquatic Ecosystem Health and Management Society (AEHMS). The mission of the Society is “to encourage and promote integrated ecosystemic and holistic initiatives for the protection and conservation of global aquatic resources.” It focuses on “adoption of ecosystem health concepts and practices in relation to remediation and restoration of stressed aquatic ecosystems.” Its mandate includes the organization of conferences and workshops and the publication of its primary journal, Aquatic Ecosystem Health and Management (AEHM), and books in the Ecovision World Monograph Series.A total of 42 special issues of the journal have been published to date. Over half of the issues contain contributions pertaining to the Laurentian Great Lakes, with the remainder devoted to aquatic ecosystems in other temperate and tropical regions worldwide. Publication of books in the Ecovision World Monograph Series commenced in 1995 with “The Lake Huron Ecosystem: Ecology, Fisheries and Management.” Of the 21 Ecovision books published to date, 10 directly concern the Laurentian Great lakes including the landmark State of the Lakes volumes. Other volumes feature ecosystem concepts and aquatic resources in Mexico, China, the Persian Gulf, the Nordic Region, the Himalayas and other Great Lakes of the world.The global scope of both the special issues and Ecovision publications reflects the mandate of AEHMS to promote an integrated ecosystem-based approach to aquatic ecology in the Northern and Southern hemispheres. Most of the publications are proceedings of conferences and workshops organized by AEHMS alone, or with other organizations. This process is ongoing. Publications in progress include results from studies in Sweden, India, Africa, Lake Ontario, Bay of Quinte and Hamilton Harbour. Clearly, the mission and mandate established by the Society in 1989 have been fulfilled and will continue into the future.The amount and scope of information on global aquatic ecosystems organized and published by AEHMS is enormous. This would not have been possible without the foresight and outstanding leadership provided by Dr. Mohi Munawar, President of AEHMS and Chief Editor of AEHM and Ecovision World Monograph Series. He initiated the concept of the Society, organized it and has managed its activities since inception.Dr. Munawar's energy and productivity are legendary. Peer respect is reflected in the eight distinguished awards he has received to date including all three major awards from the International Association for Great Lakes Research. His contributions to Great Lakes science through his research activities and numerous publications are without parallel in the Great Lakes research community. His enormous contributions to aquatic ecosystem science through AEHMS are recognized and appreciated globally as evidenced by the international awards he has received including an Honorary Doctorate from Gothenburg University, Sweden and a Fellowship from The Aca- demy of Science, Engineering and Technology of India.Dr. Munawar is the originator and prime motivator of a world-class ecological society and the wealth of information accruing over more than two decades would not have been generated without his initiative and dedication. It is also important to mention that the AEHMS has a competent, diligent and dedicated editorial staff which ensures that each issue of the journal and Ecovision volumes is published with the utmost quality and excellence.

Can simple phosphorus mass balance models guide management decisions? A case study in the Bay of Quinte, Ontario, Canada

We test the capacity of an existing simple mass-balance total phosphorus (TP) model to evaluate nutrient loading scenarios in the Bay of Quinte, Ontario, Canada. Our study examines whether model parameters and loading inputs are well characterized and relevant to the current conditions in the Bay of Quinte and its drainage areas. We also identify critical data gaps and influential assumptions in regard to the uncertainty of model outputs and the credibility of predictive statements about the achievability of delisting objectives of the system. Our analysis shows that the model closely reproduced the observed variability of the TP seasonal averages during the calibration period 1972–2001, but its performance was significantly reduced when the actual predictive capacity was assessed in the 2002–2009 validation period. The most troublesome result is the inability of the model to reproduce the observed TP variability at temporal scales that are more meaningful from an environmental management point of view (i.e., monthly averages or daily snapshots from the system). Sensitivity analysis shows that several parameters associated with the role of the sediments were significant drivers of the model outputs, suggesting that considerable uncertainty exists in regard to the characterization of the sediments. The loadings from Trent River and the TP levels of the inflowing water masses from Lake Ontario predominantly shape the variability in the upper and lower segments of the Bay of Quinte, respectively. We also present a critical review of the suitability of the existing water quality criteria to depict the trophic status throughout the system. Our study contends that the summer average TP concentrations do not adequately reflect the prevailing conditions and that the development of proper water quality criteria should place more emphasis on inshore sites, where the eutrophication problems are more frequently manifested. Finally, we pinpoint factors unaccounted for by the original model that are likely to modulate the response of the system in its present state. We also discuss important directions of model structure augmentation and ways to optimize the spatial segmentation.

Improving the representation of internal nutrient recycling with phosphorus mass balance models: A case study in the Bay of Quinte, Ontario, Canada

We evaluate the relative importance of the causal connection between exogenous total phosphorus (TP) loading and internal nutrient recycling with the water quality conditions in the Bay of Quinte, Ontario, Canada. First, we examine the temporal trends of all the major point and non-point loading sources over the last four decades. We then enhance the mechanistic foundation of an existing simple mass-balance total phosphorus (TP) model, originally developed to guide the eutrophication management in the system. The structural improvements include the incorporation of macrophyte dynamics, the explicit representation of the role of dreissenids in the system, and the improved portrayal of the interplay between water column and sediments. The upgraded model was in good agreement with the observed TP variability in the system during the study period (2002–2009) and successfully reproduced the TP accumulation patterns toward the end of the summer-early fall. We provide evidence that phosphorus dynamics in the upper Bay are predominantly driven by the inflows from Trent River, while the middle and lower segments likely receive substantial internal subsidies from the sediment diagenesis mechanisms and/or the activity of macrophytes and dreissenids (e.g., pseudofeces production, nutrient pump effect). We also forced the model with scenarios of reduced nutrient loading and examine the likelihood of the system to meet its water quality delisting targets, although we caution that our complex overparameterized modeling construct is primarily intended for heuristic purposes. The present study together with the companion paper by Zhang et al. (2013) illustrate how phosphorus mass balance models can offer useful tools for improving our understanding of freshwater ecosystems.

Assessing the fish consumption beneficial use impairment in the Bay of Quinte

The state of contamination in Bay of Quinte fish was assessed to determine whether delisting criteria have been met, and to recommend further studies/actions to be undertaken. We examined fish contaminant data collected by the Ontario Ministry of the Environment between 1975 and 2008 for seven sites in Lake Ontario including the Bay of Quinte. Where sufficient data was available, we tested for differences in recent years by examining the post-1998 data for Walleye, Smallmouth Bass, Yellow Perch and Brown Bullhead. Our analysis specifically focused on known contaminants of concern within the Bay of Quinte: polychlorinated biphenyls (PCBs), mercury (Hg), as well as Mirex which is known to originate from Lake Ontario. Insufficient data was available for the examination of total TEQs (dioxins, furans and dioxin-like PCBs). When appropriate, we used the general linear model (GLM) to compare contaminant concentrations among sites as a function of fish length. When no significant relationship between contaminant concentration and fish length was found, mean values among sites were compared using analysis of variance. While there were no significant differences for the majority of contaminants among sites, some species and contaminant combinations at one or more of the Bay of Quinte sites had elevated fish concentrations compared to some reference sites. For instance, mercury concentrations in Yellow Perch and Brown Bullhead at Quinte sites exceeded those from some reference sites. Current consumption restrictions for Brown Bullhead and Yellow Perch are more severe in the Upper Bay of Quinte compared to the other sites, indicating impacts of local sources. As a result, the fish consumption beneficial use impairment continues to be classified as impaired for the Bay of Quinte. As many sport fish such as Walleye and Smallmouth Bass are large, long-lived and potentially wide-ranging species, it is difficult to link contaminant concentrations to local sources. To investigate the impact of sources within the Upper Bay of Quinte, comparison of contaminants in sentinel fish collected on the same scale as the source of the contamination is recommended.

Communicating research findings and monitoring data in support of management: A case study of the Bay of Quinte Remedial Action Plan

The Bay of Quinte is a nearly enclosed bay in Lake Ontario which has been impacted by multiple industrial contaminant events and persistent eutrophication. As a result, it became one of 43 Great Lakes Areas of Concern (AOC) identified and supported by the International Joint Commission (IJC) for remediation. The Bay of Quinte Remedial Action Plan (RAP) relies on data from Project Quinte, a long-term monitoring program, to set targets, assess the status of beneficial use impairments and evaluate restoration progress. The ability of organizations to communicate relevant and timely scientific research and monitoring to decision-makers has recently emerged as an important issue in the literature. This article explores the issue of communicating research and monitoring information for the purpose of aiding decision-making through a case study of the Bay of Quinte RAP. Research included semi-structured interviews with scientists, regulators and community stakeholders involved with the Bay of Quinte RAP, observational research, document analysis and literature review. Findings indicate that multiple and diverse techniques are used to communicate research and monitoring data to decision-makers. Furthermore, our findings indicate that accurate tracking of trends, valuing high quality monitoring, promoting stakeholder cooperation, collaborating with other groups implementing RAPs and informing management and decision-making are key beneficial outcomes of shared science about the Bay of Quinte. Lessons learned emphasize the importance of administrative support and institutional memory; integration of ecosystem models; consistent long-term monitoring; and public engagement. These lessons are instructive for stakeholders conducting ecosystem restoration, planning or management, particularly those involved in any of the other RAPs ongoing on the Great Lakes.

Phosphorus and chlorophyll in the Bay of Quinte: A time-series/intervention analysis of 1972–2008 data

Three independent methods of time-series analysis were applied to a 37-year record of total phosphorus and chlorophyll-a data collected at four sampling stations representing the upper, middle and lower sections of the Bay of Quinte, NE Lake Ontario, Canada. The three methods were used to build consensus around the significance of the apparent declines in total phosphorus (TP) and chlorophyll-a (Chl-a) concentrations following two interventions: (1) point-source phosphorus loading reductions of about 50% to the upper bay in the winter of 1977–1978 and (2) the establishment of Zebra Mussels (Dreissena spp.) in the early to mid-1990's. The methods were applied to May to October monthly means and included: (1) nonparametric tests that accounted for persistence and seasonality and determined the statistical significance of step-trends, (2) ARIMA-Intervention modelling that produced forecasts into post-intervention time periods that were compared statistically to measured data and (3) regime shift detection for identifying the significance of persistent steps after removal of the seasonal components of the data series (modelled as periodic functions). Strong gradients in total phosphorus (TP) and Chl-a concentrations between the upper and lower Bay of Quinte still existed three decades after reductions in point-source loadings of TP to the upper bay, where, during 2000–2008, May-October average TP was 3.8 times higher and Chl-a, 2.9 times higher than in the lower bay. The Remedial Action Plan May-October TP objective of 0.030 mg l-1 for the upper Bay of Quinte was not achieved consistently in recent years. Concurrence among the data analysis methods suggests that the relative decreases in the upper bay TP (31%) and Chl-a (37%) after phosphorus loading reductions were greater than in the lower bay (0% and 10%, respectively). The relative decreases in the upper bay TP (0%) and Chl-a (29%) associated with Dreissena establishment were less than those measured in the lower bay (20% and 50%, respectively).

Submerged aquatic vegetation in the Bay of Quinte: Response to decreased phosphorous loading and Zebra Mussel invasion

Originally mesotrophic, the Bay of Quinte ecosystem has experienced eutrophication since the 1940s, which resulted in the decline of once-lush submerged aquatic vegetation (SAV) beds in the upper bay by the mid-1960s. Since 1972, twelve SAV surveys have been conducted along ten index transects, recording:% cover, distance SAV beds extended from shore (extent), maximum depth of colonization (Zc), species composition, and, in later years, wet plant biomass. Offshore secchi depth and ϵpar, (the vertical light extinction rate (m−1) for photosynthetically active radiation), were also recorded either weekly or bi-weekly during the growing season since 1972. During this time, two major changes occurred within the bay: the reduction in point-source phosphorus (P-control) loadings in 1978 and the 1993 invasion by Dreissenid Mussel. SAV response to these changes varied temporally and spatially, with the shallow upper bay showing the greatest response, particularly after Zebra Mussels establishment. In the upper bay, mean secchi depth increased by 8% from 1.2 m prior to P-control (pre-P), to 1.3 m after P-control (post-P) and further increased by 46% to 1.9 m after Dreissena establishment (post-D). Upper bay SAV responded to these invasive species with increases in the means of three variables: Zc from 1.6 to 3.5 m, extent from 114 m to 417 m and wet biomass from 50 g m−2 to 962 g m−2. SAV in the middle and lower bays were in better condition in 1972, with pre-P cover in excess of 50% and Zc of 2.6 and 3.7 m, respectively. SAV cover did increase in the post-D (1994 to 2007) period by approximately 25% and Zc increased to 3.7 and 6.5 m, but the narrow fringing strip of shallower water along the shore in these two deeper bays limited substantial increases in bed extent. Both water clarity and basin morphometry strongly influenced SAV distribution and abundance within the Bay of Quinte.

Fish community structure in the Bay of Quinte, Lake Ontario: The influence of nutrient levels and invasive species

Intensive, long-term sampling in the Bay of Quinte with multiple gears (i.e. gill nets, bottom trawls, trap nets and boat electrofishing) allowed examination of the fish community and major fish populations in the context of key stressors up to 2009. Excessive nutrient input and hyper-abundant non-native fish species, White Perch and Alewife, shaped the depreciated fish community of the 1970s. After implementation of phosphorus input control measures and simultaneous winter-kills of the hyper-abundant non-native fish in the late 1970s, Walleye recovered and served to restore a predator-prey balance to the fish community by the late 1980s. However, in the absence of a significant recovery of submerged aquatic vegetation (SAV) in littoral areas, off-shore species (e.g. Alewife and White Perch) still tended to dominate; even in littoral areas. Following establishment of Dreissenid Mussels in the mid-1990s, water transparency increased and SAV increased significantly in littoral areas. This pivotal event led to a shift in the fish community that included an overall decline in Walleye, an increase followed by a decrease in Yellow Perch, and dominance by centrarchids (i.e. Bluegill, Pumpkinseed, Black Crappie and Largemouth Bass) in the nearshore. Round Goby invaded in 1999, proliferated and became important in the diet of piscivores by 2003. The current species assemblage, including the piscivores, is diverse and indicative of a healthy fish community.