CAISN 2011 AGM Programme

Page 1

Final Conference Programme April 27-28, 2011 Quebec City, Quebec

CAISN Annual General Meeting Programme 2011

Table of Contents

Venue Information 2. 2 Wine & Cheese Reception Information 3. 3 Agenda 4-5

Speaker Bios. Janet Walden 6. Siddika Mithani 7.

6 7

Wednesday. Keynote Speaker, James Carlton 8-9. Oral Presentations 10-14.

8-9 10-14

Thursday. Keynote Speaker, Julian Olden 15. Oral Presentations 16-25. Poster Presentation Abstracts: Series I 26-30. Poster Presentation Abstracts: Series II 31-34. Closing Banquet Information 35.

15 16-25 26-30 31-34 35

Quebec City, Quebec April 27–28, 2011



Loews Hôtel le Concorde Québec City, Québec

Experience the Very Best at Loews Hotels In the heart of Québec City, Loews Hôtel Le Concorde brings a FourDiamond and more service to this charming city. Surrounded by the City of Québec you will feel like you are in a European city as you traverse the winding cobblestone streets of the Old City.

Loews Hôtel Le Concorde Hotel features: • • • • • • • • •

406 spacious rooms (364 sq. ft.) and suites with views, including 17 suites and 2 duplex penthouse suites Exercise room, saunas, whirlpool and heated outdoor pool (in season) Multilingual staff and full-service concierge Uniquely local gift shops Our revolving rooftop restaurant-Bar L’Astral In-room dining from 6:30am to 11:00pm everyday Business Workstations in the lobby Wireless high-speed Internet access Valet parking

Phone: (418) 647-2222 Fax: (418) 647-4710

CAISN Poster Display

1225 cours du Général-De Montcalm Québec City, Québec, G1R 4W6

Third Floor

2 Canadian Aquatic Invasive Species Network Final Conference Programme 2011

Wine & Chese Reception

Morrin Cultural Centre Wednesday, April 27, 2011 5:30 pm – 7:30 pm

Join us for a wine and cheese gathering followed by a walk through foreboding jail cells. See messages scratched into the stone by inmates and the iron rings used to chain them to the floor. Then browse the books in the charming Victorian library, housing unique masterpieces dating from 1613 up to the present day. Professional tour guides will be taking us through the building and unlocking the stories hidden in the bones of this historic building.

Quebec City, Quebec April 27–28, 2011


Agenda Wednesday, April 27, 2011

Agenda Thursday, April 28, 2011

All Meeting Sessions are located the Borduas Room – 3rd Floor Loews Hotel

All Meeting Sessions are located the Borduas Room – 3rd Floor Loews Hotel

7:30 - 8:00 am Hot Breakfast “Le Montcalm” La Galerie 8:00 – 8:20 am Welcome and Introductions from the Borduas Room Scientific Chair, Hugh MacIsaac 8:20 – 8:35 am Janet Walden, Vice-President, Research Partnerships NSERC 8:35 – 8:50 am Siddika Mithani, Assistant Deputy Minister, Fisheries and Oceans 8:50 – 9:00 am David Yard, Senior Marine Safety, Transport Canada 9:00 – 10:00 am Keynote Speaker: James Carlton, Professor of Marine Sciences and Director of the Williams College - Mystic Seaport Maritime Studies Program

8:00 – 8:30 am Continental Breakfast La Galerie 8:30 – 8:40 am Welcome Back from the Scientific Borduas Room Chair; Introduction of Keynote Speaker, Julian Olden 8:40 – 9:40 am Julian Olden, University of Washington

7:30 am – 7:00 pm

“Some Principles of Invasion and Vector Science 10:00 –10:30 am Question Period 10:30 –10:50 am Morning Break 10:50 –11:30 am “Regional Variation in Shipping Pathways and Vectors Across Canada”, Sarah Bailey 11:30 –11:50 am “Intertidal Surveys: Contrasting levels of invasion on Pacific and Atlantic coasts”, Francis Choi 11:50 –12:10 pm “Hull fouling as a Vector for the Introduction of Nonindigenous Species”, Abisola Adebayo 12:10 -12:30 pm “A mechanistic model for invasions: using environment as a predictor of copepod population success”, Carly Strasser 12:30 – 1:30 pm Lunch 1:30 – 2:10 pm “Evolutionary Genetics of Aquatic Invasions: From Past to Present Invasions”, Melania Cristescu 2:10 - 2:50 pm “Regulators of the spread and establishment of the spiny water flea, Bythotrephes: the power of a research network”, Norman Yan 2:50 – 3:10 pm “Estimating the probability of NIS establishment from Canadian live fish import data”, Johanna Bradie 3:10 – 3:30 pm “Pathway analysis of species introductions: Identifying critical targets for prevention management”, Andrew Drake 3:30 – 3:45 pm Afternoon Break 3:45 – 4:05 pm “A synthesis of exotic biofouling species in Canadian coastal waters; hot spots and related vectors”, Anais LacoursiereRoussel 4:05 – 4:35 pm Synthesis Talk on Transoceanic sampling – Claudio DiBacco 5:30 – 7:00 pm Wine and Cheese Reception Morrin Cultural Centre 4

8:00 am – 8:30 pm

“Invasive Species and Alternative Global Futures for Freshwater Ecosystems” 9:40 –10:10 am Question Period 10:10 –10:30 am “Jump or creep: Population genetic structure and dispersal dynamics of the introduced golden mussel Limnoperna fortunei in South America”, Aibin Zhan 10:30 – 10:50 am Coffee Break 10:50- 11:10 am “Risk assessment of hull fouling and ballast water discharge as vectors for aquatic non-indigenous species in the Canadian Arctic”, Farrah Chan 11:10 –11:30 am “Coastal traffic as a vector for propagule pressure on Canada’s marine coasts – The case of dinoflagellates”, Suzanne Roy 11:30 –11:50 pm “Physical and Biological Controls on Bacteria populations in ballast water during trans-oceanic voyages of bulk carriers”, Jennica Seiden 11:50 –12:10 pm “Multiple introductions and invasion pathways for the invasive ctenophore Mnemiopsis leidyi in Eurasia”, Sara Ghabooli 12:10 – 1:00 pm Lunch 1:00 – 1:20 pm “Assessing invasion risk across taxa and habitats: life stage as a determinant of invasion success”, Elizabeta Briski 1:20 – 1:40 pm Management implications for monitoring invasive tunicate Ciona intestinalis in Prince Edward Island, Samuel Collin 1:40 – 2:00 pm “Molecular phylogenetics differentiates multiple cryptic species in Botryllus schlosseri, a highly invasive ascidian”, Dan G. Bock 2:00 – 2:20 pm “Presence of native and exotic phylotypes in hotspots of Paralia diversity in Canada”, Michael MacGillivary 2:20 – 2:40 pm Afternoon Break

Canadian Aquatic Invasive Species Network Final Conference Programme 2011

2:40 – 3:00 pm “Discharge of ballast sediment residuals during deballasting procedures: A potential vector for the transfer of AIS?”, Andrea Weise 3:00 – 3:20 pm “A decade of sediment and dinocyst accumulation in the ballast tanks of a bulk carrier”, Andre Rochon 3:20 – 3:40 pm “Influence of the exotic predatory cladoceran Bythotrephes longimanus on the vertical distribution of zooplankton prey in inland lakes of the Canadian Shield”, Anneli Jokela 3:40 – 4:20 pm Poster Presentations Session I 5 minutes; 3-4 slides oral poster Asa Kestrup, “The effects of interspecific interactions andenvironmental heterogeneity on the dominance of an invasive crustacean” Annick Drouin, “Impacts of the invasive green seaweed Codium fragile in eelgrass meadows: observations vs. experiments” Karine Gagnon, “Modelling the long-range dispersal of Codium fragile” Cathryn Clarke Murray, “Drag racing invasive species – buckle up and hold on tight”

4:20 pm – 4:30 pm

Brief 10 minute break

4:30 – 5:15 pm

Poster Presentations Session II 5 minutes; 3-4 slides oral poster

Oscar Casas-Monroy, “Presence of non-indigenous dinoflagellate cysts in ballast sediments: Comparison between Canada’s East Coast, West Coast and the Great Lakes” Erin Gertzen, “Assessing the relationship between propagule pressure and probability of establishment for Bythotrephes” Patricia Pernica, “Barriers to mixing in Lake St. Clair” Yanjun Sun, “Comparisons of the dilution patterns of discharged ship ballast water in Goderich Harbour and in the St. Clair River” Suncica Avlijas, “Patterns of distribution and abundance of Hemimysis anomala in relation to physic-chemical variables” Abisola Adebayo, “Domestic ballast as a potential vector for the introduction of Nonindigenous species in the Great Lakes – St. Lawrence River”

Paul Edwards, “Patterns of dispersal of an early invader: Implications for monitoring”

Natalie Kim, “Impacts of prey quantity and quality on Bythotrephes reared in the laboratory”

Louis Ferguson, “The fertility of Ciona intestinalis eggs under mussel processing plant conditions”

Olivia Lacasse, “Is there a link between dinoflagellate cyst assemblages and shipping traffic in Nova Scotia?”

Lifei Wang, “Effects of sample size and species distribution patterns on the performance of species distribution models”

Corey Chivers, “Modeling responses to management intervention in the control of spread of freshwater invasives” 5:15 – 6:00 pm

Closed Poster Judging

Megan Mach, “Identifying exotic species in Canadian eelgrass beds at a regional and national scale”

6:30 – 8:30 pm

Dinner Banquet Jean-Paul Lemieux Room

Dinner Speaker, Warwick F. Vincent, “Our rapidly changing polar regions: Earth’s final frontier for invasive species” Announcement of Poster Contest Winners

Quebec City, Quebec April 27–28, 2011


Speaker Bios Janet Walden

Vice President Janet Walden Vice President Research Partnership Programs Research Partnerships Programs Natural Sciences and Engineering Research Council NSERC Janet Walden is the Vice President responsible for the Research Partnerships Programs with the Natural Sciences and Engineering Research Council of Canada (NSERC). Janet began her career working in the forestry industry, as an environmental chemist. In 1982, she joined NSERC and since 1997 has been Vice President for Research Partnerships. Janet is responsible for creating and evolving a highly successful spectrum of national policies and partnership programs designed to stimulate increased public-private collaborations and technology transfer, and maximize the benefits to Canada of university research.

Janet Walden is the Vice President She has 25 years of experience in She has 25 years for of experience in leadership positions with NSERC, responsible the Research leadership positions with NSERC, including 7 years as Director of the Networks of Centres of Excellence. Partnerships Programs with the Natural including 7 years as Director of the Under her guidance, NSERC’s partnership initiatives have grown to over $180M and per annum involving Research more than 3,600 university Sciences Engineering Networks of Centres of Excellence. researchers and over 1,400 companies annually. Council of Canada (NSERC). Under her guidance, NSERC’s partnership initiatives have grown to Janet began her career working in the over $180M per annum involving more forestry industry, as an environmental than 3,600 university researchers and chemist. In 1982, she joined NSERC and since 1997 has been Vice President over 1,400 companies annually. for Research Partnerships. Janet is responsible for creating and evolving a highly successful spectrum of national policies and partnership programs designed tostimulate increased publicprivate collaborations and technology transfer, and maximize the benefits to Canada of university research.

6 Canadian Aquatic Invasive Species Network Final Conference Programme 2011

Siddika Mithani

Assistant Deputy Minister Fisheries and Oceans

As announced in November 2009, the merger of the Oceans Directorate and the Science Sector, NCR, will come into effect on February 22, 2010. I am pleased to announce the deployment of Dr. Siddika Mithani, to the position of Assistant Deputy Minister (ADM), Oceans and Science Sector in the NCR, effective on the same day. Since 2007, Dr. Mithani has held the position of Associate ADM, Health Products and Food Branch at Health Canada. Over the years, she has acquired years of experience providing leadership and managing science, policy and regulatory initiatives at both the national and international levels. With at least 10 years of experience at Health Canada, she will bring knowledge and expertise in the areas of safety, efficacy, quality and risk management principles in the health and industry sectors as well as risk management in complex regulatory science programs which balance the needs of both the Canadian public and the views of stakeholders.

Dr. Mithani is a recipient of the Queen’s Medal for her work in the area of developing and implementing regulations for clinical drug trials in Canada, and has been extensively involved in difficult food and nutrition files. Holding a Bachelor of Science degree in Pharmacy and a Ph.D. in Psychopharmacology from the University of Aston in Birmingham, England, she maintains her practising pharmacist license with the Ontario College of Pharmacists by being involved in pharmacy practice where feasible.

Quebec City, Quebec April 27–28, 2011


Wednesday, April 27, 2011 Keynote Speaker

James T. Carlton

Professor of Marine Sciences and Director of the Williams College - Mystic Seaport Maritime Studies Program

Dr. Carlton, Professor of Marine Sciences and Director of the Williams College - Mystic Seaport Maritime Studies Program, has studied aquatic invasions since 1962. His studies have included the history, dispersal vectors, biogeography, and ecology of introduced marine species along the Atlantic, Gulf, and Pacific coasts of North America, as well as in the Hawaiian Islands. Dr. Carlton feels that we must effectively use the Aquatic Nuisance Species Task Force and the National Invasive Species Council to focus, coordinate and synchronize research and education mandates, and he himself has been a participant of the


Canadian Aquatic Invasive Species Network Final Conference Programme 2011

Invasive Species Focus Team for the Gulf of Mexico Program. Dr. Carlton’s research encompasses two aspects of the history of life in the world’s oceans: world-wide biological invasions of non-native species in coastal environments and modernday extinctions of marine organisms in sensitive marine and estuarine habitats. In 1996, he was awarded the prestigious Pew Fellowship. He is the founding editor-in-chief of the journal Biological Invasions and was principal investigator of the NOAA Sea Grant National Biological Invasions Shipping Study. Dr. Carlton was also the principal

Some Principles of Invasion and Vector Science

investigator of one of the first Sea Grant studies of the invasion of European zebra mussels in the Great Lakes. He co-chaired the National Academy of Sciences’ marine biodiversity panel, and in 1999 was the first U.S. scientist to be awarded the federal government’s Interagency Task Force Award for his national and international work to reduce the impacts of exotic invasions in the sea. As Director of the Williams-Mystic Program, Dr. Carlton is committed to developing a curriculum that inspires undergraduates to pursue integrated investigations, across the disciplines of science, history, and policy, in the field of maritime studies.

The scale of invasions in aquatic (marine, estuarine, and freshwater) ecosystems has been significantly underestimated. This underestimation derives from two primary sources: (1) it may be that the majority of species introduced during the first 500 years of global commerce have escaped recognition, potentially strongly skewing our perceptions of the evolution and history of many nearshore communities, and (2) invasions of smaller-bodied and taxonomically more challenging species are reported far less often than invasions of larger-bodied and taxonomically more accessible taxa. The combination of the two suggests that many fundamental but overlooked shifts have occurred in marine ecosystems, and the latter suggests that many current invasions go unreported. In terms of ecological and environmental assessments, an enduring statement in the literature is that most invasions are benign and appear to have little or no impact, but no experimental or quantitative data are available that support that conclusion. Vector science focuses on a framework that abandons the term “pathway” in favor of a focus on cause, route, and vector itself, and characterizes patterns in terms of vector tempo, vector biota, and vector strength. A critical direction forward is the concept of Integrated Vector Management (IVM), which captures all aspects and layers of the invasion matrix from source to donor region, embedded in a world of climate change. Equally critical is the recognition of a polyvectic world (including qualitative and quantitative data on active causes, routes, and vectors in a given management region), and then re-defining management boundaries on a biogeographic and not political basis.

Quebec City, Quebec April 27–28, 2011


Wednesday, April 27, 2011

Oral Presentations Sarah Bailey

Francis Choi

Regional Variation in Shipping Pathways and Vectors Across Canada

Intertidal Surveys: Contrasting levels of invasion on Pacific and Atlantic coasts

The most effective strategy for managing non-indigenous species (NIS) is through prevention via regulation of introduction pathways and vectors. Transporting 90% of the world’s trade, commercial shipping activities have been a leading mechanism for aquatic NIS introductions globally. CAISN researchers sampled 299 ships arriving to three different regions of Canada (west coast, east coast and Great Lakes) to assess colonization and propagule pressure posed by aquatic taxa transported incidentally by commercial shipping activities. Goals of the project were to determine the relative importance of different shipping pathways (transoceanic or coastal shipping) and vectors (ballast water and ballast sediments) for a wide variety of taxa, including invertebrates, diatoms, dinoflagellates, bacteria and viruses. In addition, CAISN researchers investigated the efficacy of ballast water exchange as a management practice. Results of this project indicate that colonization and propagule pressure are differentially influenced by region, pathway, vector and taxon and reveal strategies to further reduce invasion risk.

The establishment of non-indigenous species in natural ecosystems is a growing concern at global, national, and regional scales. Over 100 known marine non-indigenous species (NIS) are found along the Pacific and Atlantic coasts of Canada. It is widely believed that commercial shipping activities associated with international ports (eg. ballast water discharge, hull fouling…) could expose native environments to a variety of potential NIS. Therefore, harbours are recognized as a critical entry point for potential NIS and, pending establishment, can serve as an invasion hub for secondary dispersal vectors (e.g. recreational boats). Although, harbours are critical invasion locations, relatively little is known about the distribution and abundance of NIS in port communities in Canada. In the summer of 2007 and 2008, extensive intertidal surveys were conducted to examine spatial patterns in intertidal community structure, including the distribution of NIS in Canadian ports. Sixteen major international ports, eight along the Pacific coast and eight along the Atlantic coast were surveyed for richness and abundance of both native and non-indigenous marine intertidal

Fisheries and Oceans Canada

University of British Columbia

10 Canadian Aquatic Invasive Species Network Final Conference Programme 2011

species. Results showed significant differences both among ports and between coasts with respect to native and NIS composition. NIS richness was higher on the Pacific coast, but the contribution of each species to total abundance was much lower. For coastal regions of Canada our data suggest: 1) for intertidal communities in Canadian ports, the establishment of non-indigenous species appears dependent on an “environmental-based invasion” rather than dependence on biological resistance by existing native diversity; and 2) ecosystems situated in similar latitude zones but on opposite sides of the continent exhibit significant differences both in species composition and distribution, including the importance of NIS in these ecosystems. Future risk assessment models should consider treating coastal ecosystems independently, to prevent false predictions due to regional differences that could be heavily biased by historic events.

Abisola Adebayo GLIER, University of Windsor

Hull fouling as a vector for the introduction of nonindigenous species

Hull fouling is an important vector for the dispersal of nonindigenous species (NIS) in marine and coastal ecosystem; despite this hull fouling studies are rare. During 2007 – 2009, divers conducted in situ sampling of harbour fouling communities on the east and west coast, they also sampled and recorded video transects of the hull of 20 vessels in the Great Lakes, east, and west coasts of Canada. Results indicate that hull fouling appears to be a low risk vector for NIS introduction to the Great Lakes. Only one dead individual of a freshwater NIS (Alexandrovia onegensis, Oligochaeta) not yet reported in the Great Lakes was detected. In contrast, hull fouling appears to be a strong vector on the coasts of Canada, where low Sørensen’s similarity values of 0.03 in Halifax and 0.01 in Vancouver indicated a high divergence between hull and harbour communities. Propagule (up to 600,000 ind./ship) and colonization pressure (up to 156 species/ship) were high for both ports, with Vancouver receiving much higher abundances and diversity of potential NIS. Time spent in previous port-of-call and time since last application of antifouling paint were positively related to increasing propagule pressure, whereas colonization pressure increased with time since last painting and the number of regions visited by the ship. Propagule and colonization pressure were inversely related to time spent at sea and latitude of ports visited. The results presented here indicate that hull fouling has a strong potential for introduction of NIS to coastal, marine habitats and management should be considered.

Carly Strasser

National Center for Ecological Analysis and Synthesis, UCSB

A mechanistic model for invasions: Using environment as a predictor of copepod population success We used a birth rate model to determine the environmental niche for an estuarine copepod in terms of salinity and temperature. We then expanded the model application to compare growth rates of two (sub)species that may share the same environment. One potential use of this application is for comparing multiple species or subspecies to understand the dynamics of a community where environmental niches may overlap. This might be particularly useful in ecosystems subject to invasion by a species that shares demographic characteristics with an established species, such as non-indigenous copepod taxa introduced via ballast discharge. We conducted laboratory experiments to estimate demographic parameters over a range of three temperatures crossed with three salinities for the estuarine copepod Eurytemora affinis collected from the Nanaimo Estuary, British Columbia. These parameters were then used in our model to explore what environmental combinations of temperature and salinity resulted in population growth versus decline. For comparing (sub) species, we re-parameterized our model using previously published data for E. affinis collected in the Seine Estuary, France and compared population dynamics between this population and the population from BC.

Melania Cristescu GLIER, University of Windsor

Evolutionary genetics of aquatic invasions: From past to present invasions

Biological invasions are natural processes. Species have constantly experienced range expansions and contractions under the continuous evolutionary forces of a changing environment. These dynamic changes in population structure and demography have triggered waves of extinctions and radiations that have ultimately shaped the Earth’s biodiversity. However, contemporary rates of human-mediated invasions are orders of magnitude higher than historical levels of invasions. This exceptionally high rate of invasions has triggered a sharp biodiversity decline. Widespread aquatic invaders, such as tunicates, enable us to investigate how invasion history, life history traits, and stochastic events influence colonization dynamics across invaded areas. Our results, based on phylogenetic and population genetic analyses, indicate that many prevalent tunicate invaders represent assemblages of morphologically cryptic species with intricate evolutionary histories. While many tunicate lineages remain geographically restricted or are facing extinction, their close relatives are quickly reaching a global distribution. The genetic structure of such highly invasive tunicate lineages indicates recent population expansion, relatively high global homogeneity, and contrasting patterns of spread across invaded regions. We discuss how evolutionary genetic data can inform conservation policy when “the world is becoming irretrievably different”.

Quebec City, Quebec April 27–28, 2011 11

Wednesday, April 27, 2011

Oral Presentations Norman Yan

Johanna Bradie

Regulators of the spread and establishment of the spiny water flea, Bythotrephes: the power of a research network

Estimating the probability of NIS establishment from Canadian live fish import data

York University

The spiny water flea, Bythotrephes, was selected by CAISN as a model freshwater non-indigenous species for three reasons. It is the world’s best studied freshwater planktonic invader; it is spreading rapidly among inland lakes in the watershed of the Laurentian Great Lakes; and invasions in North America are consistently followed by substantial damage to pelagic biodiversity. CAISN researchers applied manifold techniques to assess the risk of spread and establishment of the spiny water flea in Shield lakes, and the widespread agreement among these many studies adds great weight to their results. Selected highlights of the research are: 1) two of the world’s largest, probabilistically designed, synoptic Bythotrephes surveys proved the ongoing rapid spread and establishment of this invader, almost tripling the number of known invasions in the region; 2) the evidence from both field observations and gravity models that humans are much more important vectors of spread than is natural dispersal among lakes in connected landscapes; 3) the consistent evidence from gravity and population-based models and an in situ experiment that the establishment success of Bythotrephes is subject to Allee affect thresholds; 4) the multiple lines of evidence that while propagule size and timing linked to human-assisted

McGill University

introductions are the key factors in spread and establishment, that knowledge of lake chemistry, especially lake pH, and the presence of sport fish improves predictions; 5) that vertical migratory behaviour of the invader interacts with wind-induced water mass movements to form large invader patches which can be delivered to lake outflows to initiate dispersal events, 6) that ongoing climate change has a complex interaction with the spread and establishment of Bythotrephes, with small temperature increases likely reducing Allee effect thresholds, fostering spread, while larger forecast temperature increases will likely kill this cold stenotherm, eventually setting geographic limits to spread; and 7) that ongoing calcium decline on the Shield will not slow the spread of Bythotrephes, rather it will likely increase the damage to its planktonic prey, which have higher Ca needs. CAISN’s research has profoundly increased our understanding of the threat posed by this damaging invader, and provided greatly improved tools which can be applied to the study, assessment and management of other invasions. Keys to this success were excellent interactions among field ecologists and modelers fostered by the network, and the fine work of HQP, many of whom have now moved into Canada’s workforce.

12 Canadian Aquatic Invasive Species Network Final Conference Programme 2011

Aquarium introductions have been responsible for 10 NIS established in the Great Lakes, up to 40 NIS established in North America, and one-third of the world’s worst aquatic NIS. Previous research on the aquarium vector has quantified the probability of live release, identified fish at risk for invasion, and qualitatively described the relationship between establishment and propagule pressure. This study attempts to quantify the relationship between propagule pressure and establishment for the aquarium trade using Canadian records for live fish imports in 2004/2005 as a surrogate for propagule pressure. Intuitively, the probability of establishment increases with propagule pressure; however, this relationship has rarely been quantified. This is in part due to a lack of information on introductions, but also due to the uncertainty and stochasticity inherent in the invasion process. Nevertheless, there is a need to generate estimates of establishment probability and the associated uncertainty for use in risk analyses. The results of this study will not only help quantify the probability of NIS establishment via the aquarium trade, but may also enable managers to determine necessary import restrictions.

Andrew Drake

Fisheries and Oceans Canada

Pathway analysis of species introductions: Identifying critical targets for prevention management

Prevention is recognized as the most effective use of management resources to control aquatic invasions. To identify pathways that pose risk of aquatic invasive species (AIS) introduction, estimates of the number of propagules released, and their spatial context across the aquatic landscape, are necessary. The baitfish pathway in Ontario is one of several secondary pathways that have the potential to transfer AIS within and beyond the Laurentian Great Lakes basin. We quantitatively examined the risk of AIS introduction through the baitfish pathway by quantifying: 1) the probability of inadvertent AIS sale to the angler; 2) the probability of angler risk activity (e.g., bait-bucket release); and, 3) the spatial distribution of introduction events based on vector (angler) movement. Models were parameterized through empirical sampling of angler baitfish purchases and social surveys of angler behaviour. To estimate the probability of introduction, a spatiallyexplicit, agent-based model was used to predict the yearly distribution of lake introduction events across a landscape of n = 2,920 lakes. Models implied that most AIS, if released, already occur in destination waterbodies due to the overwhelming influence of the Laurentian Great Lakes and other large, invaded lakes, as preferential angling

destinations. Movements to beyond these areas occurred with reduced probability; however, the large number of event trials (an estimated average of 4.12 million yearly baitfish events) confirmed that species introductions across uninvaded lake ecosystems were possible. For example, models predicted a maximum of n = 1,495 introduction events associated with angler purchase, movement and release of Round Goby (Neogobius melanostomus) to lakes that do not currently support the species. To determine the parameters (e.g., P release) having the greatest influence on lake-specific and overall probabilities of introduction, a sensitivity-based model approach was used to observe patterns of lake introduction in relation to varied parameter inputs. Model sensitivity results implied that the probability of AIS purchase by anglers had the greatest influence on the overall probability of lake introduction. Although results of pathway analysis suggest that AIS introduction may occur at current parameter values, modeling results provide meaningful managerial targets that, if achieved, will allow the probability of AIS introduction to be reduced to acceptable levels.

Quebec City, Quebec April 27–28, 2011 13

Wednesday, April 27, 2011

Oral Presentations Anais Lacoursiere-Roussel

Claudio DiBacco

A synthesis of exotic biofouling species in Canadian coastal waters; hot spots and related vectors

Synthesis Talk on Transoceanic Sampling

ISMER, Université du Québec à Rimouski

In recent years, multiple invasions of marine biofouling species have been recorded on both temperate coasts of Canada. We examine the role of human maritime vectors for the primary introduction and secondary spread of exotic biofouling species in Canadian waters. We compared the diversity of exotic biofouling species (i) at the community level among ports exposed to a gradient of shipping activity, (ii) at the population level between ports and marinas to determine the relative role of ships and boats to the establishment of primary introductions, and (iii) on boats to quantify their potential role for secondary spread in regions where boats are removed from the water each winter. Fouling macroinvertebrate communities were surveyed by diving in 8 ports on the Atlantic and Pacific coasts of Canada. Tunicate population diversity was obtained from the mitochondrial DNA cytochrome oxidase subunit I gene (COI) and 10 microsatellite markers

Fisheries and Oceans Canada

of 149 Botryllus schlosseri individuals sampled from 5 populations exposed to shipping activities (i.e. ports) and 719 B. schlosseri individuals from 21 populations exposed to local boating activities (i.e. marinas) in Nova Scotia, eastern Canada. Biofouling species were quantified on 223 boats in Nova Scotia. The richness and species composition of exotic biofouling communities on the two coasts was similar. Genetic markers indicated a loss of genetic diversity from ports to marinas, indicating a greater influence of ships than boats as vectors of primary introductions. Although boats are well-maintained in eastern Canada, all exotic tunicate species were recorded on boats there. Forty eight per cent boats were infected by B. schlosseri in the fall, suggesting the importance of this vector to the spread biofouling species. We finish with an overview of boating activity patterns in eastern Canada and discuss how this may facilitate the spread of exotic biofouling species.

14 Canadian Aquatic Invasive Species Network Final Conference Programme 2011

Scientists conducted sampling surveys on transoceanic vessels scheduled for arrival in the Port of Halifax and the Port of Vancouver from overseas sources. Ballast water samples were collected daily while the vessel crossed the open ocean on its way to Canada to examine the changes that occur in species composition for a wide variety of organisms. Data on species survivorship and environmental changes was compiled. Results will be discussed.

Thursday, April 28, 2011 Keynote Speaker

Julian Olden University of Washington

Invasive Species and Alternative Global Futures for Freshwater Ecosystems

Julian D. Olden is an Assistant Professor in the School of Aquatic and Fishery Sciences at the University of Washington. His research focuses on the ecology and management of invasive species, environmental flows, biogeography of freshwater fishes, and the development of conservation strategies in natural and built environments. This research is multi-faceted and draws upon a diverse array of disciplines including conservation biology, invasion biology, quantitative ecology, landscape ecology, biogeography, community ecology, hydrology and fisheries. Ongoing research is being conducted in Arizona, Washington, Oregon and Wisconsin, and in river systems of Australia. My research is highly collaborative and aims to integrate science-based approaches with “onthe-ground” management strategies in order to address pressing conservation questions.

Invasive species stand accused of ecological insubordination, mass murder, and other horrific crimes against nature. Ecologists have reacted by using militaristic terms such as “battle”, “harm”, “destroy”, and “meltdown” when communicating about these species. Although the use of such war metaphors in science is not new and often packs political punch, they have also led to a drastically limited perception of non-native species within society. I argue for a reconsideration of our managerial ethos towards freshwater invasive species with the hope that it encourages a constructive discourse about the undertones of invasion biology: our grief, our challenges, our opportunities and even our hopes. Freshwater ecosystems now contain a species blend of the old and the new; we must decide as a society what our future will look like, where we can control it and where we cannot. Drawing from a rich body of literature and my lab’s research I deploy a futuristic approach to postulate the possible, probable, and preferable alternative global scenarios of freshwater ecosystems in response to biological invasions and the worldviews and myths that underlie them. By capturing the essential elements of this complex issue in a fairly small number of alternative futures, my hope is that society will begin to move toward a common understanding and possible resolution and collective action (or inaction) in response to invasive species in a rapidly changing world.

Quebec City, Quebec April 27–28, 2011


Thursday, April 28, 2011

Oral Presentations Aibin Zhan

Farrah Chan

Jump or creep: Population genetic structure and dispersal dynamics of the introduced golden mussel Limnoperna fortunei in South America

Risk assessment of hull fouling and ballast water discharge as vectors for aquatic non-indigenous species in the Canadian Arctic

GLIER, University of Windsor

Dispersal dynamics hold important consequences for population genetic structure and management of introduced nonindigenous species. Natural dispersal of introduced freshwater mussels may occur by downstream “creep” associated with advection of large numbers of free-swimming larvae. In addition, local or long-distance “jump” dispersal across landscapes by larvae and/or adults may also occur owing to human activities such as shipping. These different components of stratified dispersal may produce different genetic patterns at different geographical scales. Here we explore these issues in the golden mussel Limnoperna fortunei, which is native to Asia but introduced to and widely distributed in South America. We performed genetic analyses based on a comprehensive sampling strategy

GLIER, University of Windsor

encompassing 22 populations (N = 712) throughout the invaded range in South America, using the mitochondrial cytochrome c oxidase subunit I (COI) gene and eight nuclear polymorphic microsatellites. A relatively high level of population genetic differentiation (FST = 0 - 0.108) was detected between populations throughout the invaded range. Bayesian clustering and threedimensional factorial correspondence analyses consistently revealed two genetically distinct clusters, highlighting genetic discontinuities in the invaded range in South America. Results of all genetic analyses suggest “jump” dispersal as the dominant mode of spread of golden mussels in South America, while “creep” dispersal has had very limited effects on contemporary patterns of population genetic structure.

16 Canadian Aquatic Invasive Species Network Final Conference Programme 2011

Global warming is reducing Arctic sea ice, and may provide additional navigation routes and a prolonged shipping season in the future. Therefore, the Arctic may be exposed to greater ship traffic and thus greater risk for ship-mediated invasions. We used a two-step model to identify high risk ports in the Canadian Arctic based on ship traffic and environmental suitability. First, we summarized 2005-2008 shipping data from the Canadian Coast Guard and Transport Canada, and used vessel arrivals and ballast water discharge volume as proxy measures for propagule pressure. We estimated 533 arrivals discharging 228,445 m3 of ballast water annually. Based on the number of vessel arrivals or ballast water discharged at each port, Iqaluit, NU and Churchill, MB appear to be at highest risk for aquatic non-indigenous species (AIS) introductions via hull fouling and ballast water discharge, respectively. We then compared the environmental conditions of Churchill, MB with those of the connected ports and bioregions to estimate establishment probability for potential AIS at multiple spatial scales. We determined that Port Alfred, Québec is the most likely source of AIS able to survive post-introduction at Churchill, MB. These results can be used to develop early detection programs at high risk ports and as a baseline for long-term monitoring of biological invasions as climate conditions and shipping activities in the region change.

Suzanne Roy

ISMER, Université du Québec à Rimouski

Coastal traffic as a vector for propagule pressure on canada’s marine coasts – the case of dinoflagellates There has been a lot of emphasis in the past on risks associated with the introduction of non-indigenous aquatic organisms from ballast water in trans-oceanic ships. However, a number of studies now highlight the risks associated with coastal traffic. Some regions which have received (and are still receiving) a large number of invasive species seem to act as spreading centres for other nearby coastal regions. Here, we examine if coastal traffic represents such a risk for the marine coastal waters of East and West Canada, using dinoflagellates as our target organisms. These planktonic organisms seem to survive well in ballast tanks and their interest also

stems from the fact that several of them are toxic or harmful. Our data show that coastal traffic on both coasts represents an important risk particularly for toxic/harmful species. On the East coast, domestic ships without a ballast exchange carry the greatest abundance of these organisms, while on the West coast, all domestic ships (with and without ballast exchange) have greater abundances of these toxic/harmful species compared to trans-oceanics. Ballast water exchange results in greater abundances and number of species of non-indigenous dinoflagellates (irrespective of their toxic character) on the East coast, while on the West coast, there are more

non-indigenous species in coastal ships, particularly those without ballast exchange, suggesting spreading from some US ports. Trans-oceanic ships represent the lowest risk on the West coast (both for non-indigenous and toxic/harmful species), while on the East coast, these ships bring in more non-indigenous dinoflagellates (and a greater number of toxic/harmful taxa, but at a lower concentration). While this work examines propagule supply in ballast tanks, actual establishment of non-indigenous dinoflagellates in our coastal waters may be hard to detect particularly since long-term monitoring of toxic/harmful algae has been halted almost everywhere in Canada.

Quebec City, Quebec April 27–28, 2011


Thursday, April 28, 2011

Oral Presentations Jennica M. Seiden

Ocean Sciences Center, Memorial University of Newfoundland and Labrador, St. John’s

Physical and biological controls on bacteria populations in ballast water during trans-oceanic voyages of bulk carriers We assessed (i) what changes occur to bacteria populations present in ballast water during transit from one port to another, (ii) what physical and biological factors control these changes, and (iii) the effects of MOE on the ballast water bacterial community deballasted into coastal waters during two transPacific voyages from Japan to the west coast of Canada and two transAtlantic voyages from the Netherlands to the east coast of Canada. Water samples were collected from ballast tanks that either underwent mid-ocean exchange (MOE) or were unexchanged (control). Bacterial abundances in the MOE and control tanks were not significantly different at the end of the voyage. Moreover, abundances were not lower immediately after compared with immediately before MOE suggesting MOE alone is not effective in reducing ballast water bacterial


abundances. Results of this study suggest that the duration of the voyage plays a critical role in determining the bacterial propagule pressure. Although the bacterial growth dynamics were complex, we found a significant and positive relationship between bacterial abundance and temperature and a significant and inverse relationship between bacterial abundance and dissolved oxygen concentrations. Altering the temperature and dissolved oxygen concentrations of ballast tanks could potentially be used as a management strategy for reducing bacterial populations. Moreover, we found a highly significant predictive relationship between bacterial abundance and both temperature and dissolved oxygen concentration of the ballast water (p < 0.001). By combining these two environmental parameters it is possible to predict bacterial

Canadian Aquatic Invasive Species Network Final Conference Programme 2011

abundance in ballast water and the predicted vs. observed abundances are not significantly different. This has the potential to be a very powerful management tool and provides evidence that these environmental variables could be used as a model to predict bacterial propagule pressure. Through a dilution experiment conducted during the October 2009 trans-Atlantic voyage we have determined for the first time a biological control on ballast water bacteria populations. If the microzooplankton grazer component of the ballast water microbial community is removed, bacteria growth would significantly increase. This has may have implications in ballast water treatment methods as many potential options do not rid ballast water of bacteria but do remove the grazer component of the microbial community.

Sara Ghabooli

GLIER, University of Windsor

Multiple introductions and invasion pathways for the invasive ctenophore Mnemiopsis leidyi in Eurasia The introduction and spread of nonindigenous species (NIS) in marine ecosystems accelerated during the 20th century owing to human activities, notably international shipping. Genetic analysis has proven useful in understanding the invasion history and dynamics of colonizing NIS and identifying their source population(s). Here we investigated sequence variation in the nuclear ribosomal Internal Transcribed Spacer (ITS) region of the ctenophore Mnemiopsis leidyi, a species considered as one of the most invasive globally. We surveyed five populations

from the native distribution range along the Atlantic coasts of the United States and South America, as well as eight populations in the introduced range from the Black, Azov, Caspian, Baltic, and Mediterranean Seas. Allelic and nucleotide diversity of introduced populations were comparable to those of native populations from which they were likely drawn. Introduced populations typically exhibited less genetic differentiation (lower FST values) than native populations. Population genetic analyses supported the invasion of Eurasia from at least two different

pathways, the first from the Gulf of Mexico (e.g., Tampa Bay) to the Black Sea and thence to the Caspian Sea, the second from the northern part of the native distribution range (e.g., Narragansett Bay) to the Baltic Sea. The relatively high genetic diversity observed in introduced populations is consistent with large inocula and/or multiple invasions, both of which are possible given ballast water transport and the extensive native distribution of the ctenophore in the Atlantic Ocean.

Quebec City, Quebec April 27–28, 2011


Thursday, April 28, 2011

Oral Presentations Elizabeta Briski

Samuel Collin

Assessing invasion risk across taxa and habitats: life stage as a determinant of invasion success

Management implications for monitoring the invasive tunicate Ciona intestinalis in Prince Edward Island

GLIER, University of Windsor

Many aquatic invertebrates produce dormant life history stages as a means to endure inhospitable environments and to facilitate natural long-distance dispersal, yet we have little understanding of the role of dormant stages as a mechanism for human-mediated introductions of non-indigenous species. We explore the survival of invertebrate dormant eggs in collected ships’ ballast sediment over a one year period to determine relative invasion potential across taxa (i.e. rotifers, copepods, cladocerans, bryozoans) and different habitats (freshwater, marine). During 2007 and 2008, 19 ballast samples were collected as a part of a larger study. The degradation rate of dormant eggs was assessed by enumerating dormant eggs and by conducting viability hatching experiments. Taxa examined included rotifers, copepods, anomopods, onychopods and bryozoans. Dormant eggs of rotifers degraded at the highest rate of all taxa examined, with no viable eggs remaining within ten


University of Laval

months. Copepods showed a less rapid degradation rate than rotifers. The degradation rate of anomopod dormant eggs was significantly slower than that of both rotifers and copepods. Onychopods and bryozoans did not visibly degrade at all over twelve months. Viability hatching experiments were successful for rotifers, copepods and anomopods. Onychopods and bryozoans did not hatch during any of the three hatching trials. Dormancy is not equally beneficial to all invertebrate taxa. Our results indicate that dormant eggs of rotifers and copepods degrade at a rapid rate and may not pose high invasion risk. In contrast, the slow degradation rate of anomopod dormant eggs and the lack of degradation of onychopod and bryozoan dormant eggs could result in high invasion risk due to accumulation of their dormant eggs in ballast tanks. Species having resistant dormant eggs mostly belong to freshwater taxa making freshwater habitats more vulnerable to invasion by dormant invertebrates.

Canadian Aquatic Invasive Species Network Final Conference Programme 2011

The ability to forecast the spread of Non Indigenous Species (NIS) is an essential component of successful invasion management. Identification of loci suitable for future spread increases the probability of early detection and improves chances of rapid response. The recent introduction of Ciona intestinalis in Prince Edward Island (PEI) demonstrates how efficiently some NIS are invading new environments and how quickly they can become problematic. At present C. intestinalis is contained within a few locations, but there is a high risk of further spread and broadening impacts on the aquaculture industry. The detection of C. intestinalis in Boughton Bay, Eastern PEI in 2007 provided a rare opportunity to monitor patterns and dispersal mechanisms of a known problematic species from the time of introduction. In the summers of 2008 and 2009, spatial and temporal data were taken on adult distribution and larval settlement of C. intestinalis around Boughton Bay. A rapid

Dan G. Bock

GLIER, University of Windsor

Molecular phylogenetics differentiates multiple cryptic species in Botryllus schlosseri, a highly invasive ascidian expansion in adult population density and distribution occurred between 2008 and 2009, as reflected in our larval settlement data. Over the first two years of invasion, a distinct pattern of settlement emerged, varying between 0 and approximately 35,000 larvae per station. We attempt to capture the form of this spatial pattern and the relationship between settlement density and proximity of adult populations. These data demonstrate that even on small scales (<5km), patterns of dispersal can be highly complex but are undoubtedly of great value to managers.

Recent genetic surveys of marine taxa have emphasized the commonality of cryptic speciation in the sea. Identifying previously unrecognized species diversity may be particularly important in the case of non-indigenous species (NIS). Such information can help resolve key issues of NIS invasion history, such as the cryptogenic status of widespread invaders or the sources of introduced populations. Here, we explore the evolutionary history of the golden star tunicate (Botryllus schlosseri), a species with unsettled taxonomy that has come to be recognized as one of the world’s most widespread aquatic invaders. We determine genetic patterns in 12 native European and 10 introduced North American B. schlosseri

populations, using two mitochondrial genes [cytochrome c oxidase subunit I (COI) and cytochrome oxidase b (COB)], one nuclear ribosomal gene fragment (18S), and 10 independent polymorphic microsatellite loci. Phylogenetic analyses strongly support the existence of at least three morphologically cryptic but deeply divergent lineages of B. schlosseri within the native European range. The geographic distribution of genetic variation further suggests that only one of these lineages is currently established along North American coasts. We interpret our findings in light of previous knowledge of B. schlosseri invasions, earlier genetic surveys of this widespread ascidian, and historical biogeography of European marine species.

Quebec City, Quebec April 27–28, 2011


Thursday, April 28, 2011

Oral Presentations Michael MacGillivary Mount Allison University

Assessing invasion risk across taxa and habitats: life stage as a determinant of invasion success

Paralia Heiberg is arguably one of the most recognizable, widely distributed, and commonly reported diatom genera from contemporary coastal marine environments. In three trans-Atlantic voyages (TAVs) from Europe to Canada, Paralia comprised the majority of diatoms encountered (up to 94%). We determined the morphological and genetic profile of Paralia from these TAVs and 184 monoclonal cultures of Paralia from 76 sites from Europe, the east and west coast of Canada, and other sites worldwide. The isolates were sequenced for a fragment of the RuBisCo large subunit (rbcL) gene, and the internal transcribed spacer (ITS) and 18S regions


of nuclear encoded ribosomal RNA. In total 6 phylotypes were found with 5 of the molecular variants corresponding to new Paralia species, most of them cryptic. Species of Paralia resolved included Paralia “Mexico Pacific”, Paralia “Caribbean” from Jamaica and Panama, Paralia “Europe” (formerly P. sulcata sensu Crawford, 1979) which was also present in samples from Uruguay and New Zealand, Paralia “north-northwest Pacific” from Vancouver Island and Washington State, and Paralia “panCanada 1” and Paralia “pan-Canada 2” from both the Atlantic and Pacific coasts of Canada and the United States. All sequences recovered from

Canadian Aquatic Invasive Species Network Final Conference Programme 2011

TAVs corresponded to Paralia “Europe”. Despite the number of Paralia “Europe” cells arriving to eastern Canadian waters in ships’ ballast, likely for decades, it was only detected from one site, Cheticamp, Nova Scotia. In addition, our results show the existence of two genetic hotspots for Paralia in Canada; Vancouver Island, British Columbia and Cape Breton Island, Nova Scotia as each harbours three Paralia species. If the propagule pressure of Paralia “Europe” continues to arrive at the same or at an increased rate, native Canadian Paralia diversity could potentially be most affected in these two hotspots.

AndrĂŠa M. Weise Fisheries and Oceans Canada

Discharge of ballast sediment residuals during deballasting procedures: A potential vector for the transfer of AIS? Ship’s ballast water and associated sediment residuals may be an important vector for the introduction of aquatic invasive species (AIS). Although efforts are made to minimize the uptake of sediments when loading ballast, it is not possible to prevent some entrained sediments and their associated organisms from being pumped with the water into ballast tanks. Ships cannot completely empty their ballast tanks due to structural and pumping limitations and, as a result, some ships may accumulate significant quantities of sediment after several years. Recent studies carried out by CAISN revealed that residual sediments collected from trans-oceanic and coastal ships contained adults, larvae, and resting stages of many taxa. This study addresses the existing knowledge gap concerning residual ballast sediments as a vector for the transfer of AIS. To date,

propagule pressure associated with ballast water and sediments has been calculated as the product of the quantity of ballast water or sediments discharged x the density of organisms in the ballast water or sediments x the proportion of these that are viable. However, we do not know what proportion of sediments and associated organisms are released during deballasting procedures. To address this question, we sampled a commercial bulk carrier following two consecutive trans-oceanic voyages. The objectives of this study were to 1) measure at regular intervals the concentration of suspended particulate matter (SPM) in the ballast water that was being pumped out to estimate the quantity of sediments released; 2) examine in situ sediment dynamics by mapping the distribution of sediments and organisms; 3) measure the quantity of sediments remaining in the tank to

estimate the proportion of sediments released; and 4) assess the depthdependent viability of diapausing invertebrates and dinoflagellate cysts. Preliminary results show increasing SPM concentrations towards the end of deballasting procedures, some interior hull fouling organisms (anemones, hydrozoans, and bryozoans), up to 18 cm to 30 cm of sediment accumulation in some areas of the tank, abundant invertebrate eggs with concentrations varying with sediment depth and spatially, and abundant dinoflagellate cysts with viable cysts even in the deepest sediment strata (16-18 cm). Results will help to better assess propagule pressure associated with ballast sediment release and will be relevant to the management of residual sediments and AIS.

Quebec City, Quebec April 27–28, 2011


Thursday, April 28, 2011

Oral Presentations André Rochon

ISMER, Université du Québec à Rimouski

A decade of sediment and dinocyst accumulation in the ballast tanks of a bulk carrier

Ballast water and sediments are one of the main vectors for the introduction of aquatic invasive species in Canada. In particular, sediments can contain an array of resting spores of several organisms, including dinoflagellate cysts (dinocysts). These cysts can survive several months/years in cold, dark and low oxygen conditions, and then germinate when environmental conditions become favorable. Sediments containing dinocysts are usually uptaken with ballast water in shallow coastal/ports areas, and then settle to the bottom of the tanks. When deballasting, the pumps remove much of the water, but sediments may accumulate overtime in some areas further away from the pumps.

upper 2 cm of the core, then at 2-cm intervals all the way down to 20 cm. Measurements of 210Pb were used to calculate a mean sediment accumulation rate of ca. 1.4 cm/year. Therefore, the 20 cm long sequence represents ~14 years of sediment accumulation. Subsamples of 1 cm3 were sieved with filtered sea water (salinity of 32) on 20µm Nytex membranes and 1 ml of this fraction was transferred to a SedgwickRafter cell for dinocyst counting and identification. Dinocyst counts varied between 188 and 718 specimens. The remaining fraction was incubated in F/2 –silica culture medium in a growth chamber at 10ºC (12:12 lightdark cycle) to assess the excystment potential of cysts with cell content.

downcore to reach values around 35%. No viable toxic species were observed in any of the samples, but 6 nonindigenous taxa were identified. Motile dinoflagellate cells were observed in “all” the samples after 2-3 days of incubation, and started dividing rapidly afterward.

A 20 cm long sediment core collected at the bottom of a bulk carrier performing regular trips between Europe and Canada revealed the deposition history of sediment and dinocyst accumulation at the bottom of the tank. The objectives of the study were to: 1) Document the dinocyst assemblages; 2) Determine the age of the sediments; and 3) Assess the viability of “live” cysts with incubation experiments. Sediment subsamples were collected at 1 cm intervals in the

Total cyst concentrations ranged between 320 and 2730 cysts/g dry sediment (av. 1800 cysts/g dry sediment) and reached maximum values at the top of the core. A total of 46 taxa were identified to the genus or species level (16 autotrophic and and 30 heterotrophic taxa) in all the samples. Viable dinoflagellate cysts (with cell content) represent up to 83% of the dinocyst assemblage in the upper samples and gradually decreased

3 The relative abundance of viable dinocysts is maximum at the top of the core (83%) and reach an average value of ~35% below 7 cm downcore;

24 Canadian Aquatic Invasive Species Network Final Conference Programme 2011

Although no toxic species were identified in any of the samples, this study highlights important facts: 1 The deballasting process does not remove all of the sediment from the bottom of the ballast tanks; 2 Important quantities of sediment may remain in place for long periods of time (~14 years) even after regular maintenance and cleaning schedules;

4 Despite the fact that no toxic species were found within the present study, the high number of swimming motile cells in incubated samples, even from the base of the core, highlights the threat posed by dinoflagellates as invasive organisms.

Anneli Jokela Queen’s University

Influence of the exotic predatory cladoceran Bythotrephes longimanus on the vertical distribution of zooplankton prey in inland lakes of the Canadian Shield Adaptive responses by native prey species can influence the invasion success of exotic predators. The exotic predatory cladoceran Bythotrephes longimanus is a visual predator which occupies a shallow position in the water column. Adaptive movement by zooplankton prey could have important consequences for the long-term success of Bythotrephes by reducing resource availability. A stratified field survey was conducted to determine the diel distribution of Daphnia in invaded and uninvaded lakes. We found that the epilimnetic proportion of Daphnia in invaded lakes was significantly lower during the day than at night and the epilimnetic proportion of these individuals decreased with increasing Bythotrephes density. In contrast, we found no significant difference between the day and night epilimnetic proportion

of Daphnia in uninvaded lakes. Together, these results suggest that Daphnia are migrating away from the epilimnion during the day in lakes with Bythotrephes. To further investigate this pattern, we conducted lab experiments to determine the phototactic response and vertical distribution of Daphnia from invaded and uninvaded lakes when exposed to Bythotrephes kairomone. Contrary to patterns described for the Great Lakes, we found no evidence of a behavioural response induced by Bythotrephes’ kairomone. Instead, the overall mean vertical position within the experimental columns differed between Daphnia from invaded and uninvaded lakes. These differences in the vertical position could represent the effects of selective consumptive pressure by Bythotrephes on nonmigrating individuals in invaded lakes.

Quebec City, Quebec April 27–28, 2011


Poster Abstracts Series I

Asa Kestrup

Annick Drouin

Canadian Forest Service, Natural Resources Canada

Fisheries and Oceans Canada

Impacts of the invasive green seaweed Codium fragile in eelgrass meadows: observations vs. experiments

The effects of interspecific interactions and environmental heterogeneity on the dominance of an invasive crustacean

The upper St. Lawrence River is a physically heterogeneous system that has been invaded by several Ponto-Caspian species, including the amphipod crustacean Echinogammarus ischnus. This invader is replacing the native amphipod Gammarus fasciatus in the lower Great Lakes, but the native remains dominant in the St. Lawrence River. Echinogammarus is adapted to ion-rich waters, whereas Gammarus can tolerate low conductivity. We conducted a series of experiments that tested whether local environmental conditions can explain the relative dominance of these species. We discovered that both species are mutual intraguild predators whose differing physiological tolerances influence the magnitude and direction of predation, such that a dominant predator can reverse to an inferior predator along a conductivity gradient. Additional experiments compared the survival, growth and fecundity of both species

across a range of conductivities. At low conductivity, the growth of both species is reduced and Echinogammarus also suffers higher mortality. A further study examined predation by adults on the juveniles of opposing species at different conductivities. Contrary to expectations, Gammarus had a higher Type-II functional response than Echinogammarus regardless of conductivity. This counteracts the advantage of Echinogammarus in high conductivity waters, helping to explain spatial patterns of exclusion and co-existence in the field. In addition, differential infection by a parasitic water mold (Saprolegniaceae) of unknown origin, with Echinogammarus being more vulnerable, may further explain why Echinogammarus has not successfully displaced Gammarus in ion-rich waters of the river. These results highlight the importance of context dependence in invader success and dominance.

26 Canadian Canadian Aquatic Aquatic Invasive Invasive Species Species Network Network Final Final Conference Conference Programme Programme 2011 2011

The impact of biological invasions on indigenous communities varies greatly and predicting impacts for a given system is difficult. In coastal marine ecosystems, the green seaweed Codium fragile ssp. fragile (Codium) is a notorious invader. However, its reputation is largely based on studies done on rocky shores. Codium has recently invaded soft-bottom eelgrass communities by attaching epiphytically to eelgrass (Zostera marina) rhizomes, raising concerns that it may impact these important coastal habitats through competition or disturbance. We investigated how Codium affects various aspects of eelgrass performance (shoot density and length, shoot growth, above- and below-ground biomass, and carbohydrate storage) using both small-scale manipulative and largescale observational experiments. Manipulative experiments that varied Codium abundance demonstrated

Karine Gagnon Université Laval

Modelling the long-range dispersal of Codium fragile

clear negative effects on eelgrass shoot density and carbohydrate reserves over a 4 month period, but only for the highest Codium biomass evaluated. The precise mechanism for these effects is unknown but likely involves shading of young eelgrass shoots by the algal canopy. In contrast, these effects were either not detected or very weak when examined correlatively with field surveys done at larger spatial scales, even in sites that had been invaded for 4+ years. The generalization of this species’ impact on eelgrass communities is thus premature and further efforts are required to assess the long-term threats that this invader poses to this ecosystem. This study demonstrates the need to investigate impacts of invasions over multiple scales, especially those that incorporate the temporal variability and spatial heterogeneity of the invader’s abundance.

The secondary spread of an invasive species after its initial establishment is a major factor in determining the magnitude of its economic and ecological impacts. Long-range dispersal events (jump dispersal) are particularly important as they lead to the establishment of new populations. Determining and modeling the factors driving this secondary spread is therefore of great importance to manage and predict invasions. Previous results have shown that long-range dispersal of the invasive alga Codium fragile depends on winddriven dispersal of buoyant fragments, which can then settle and give rise to new populations. The positive buoyancy of these fragments is caused by the accumulation of air bubbles within the thallus due to high levels of photosynthesis in high light intensity conditions. When light intensity is low,

these air bubbles dissipate or are used up in respiration, and fragments sink. We used a combination of field data and previously published data to create a mechanistic model incorporating photosynthesis and respiration rates for the buoyancy of Codium fragments. Using previously determined photosynthesis-irradiance curves, we were able to determine the floating time (i.e. dispersal time) of fragments under different light conditions. A dispersal model was also created, incorporating random movement (diffusion) and advection due to wind. The spread of fragments after a certain period of time was then determined for different wind speeds and directions. We compared values obtained from these models to historical spread rates, and predicted possible future spread in the Gulf of St. Lawrence.

Quebec Quebec City, City, Quebec Quebec AprilApril 27–28, 27–28, 2011 2011


Poster Abstracts Series I

Cathryn Clarke Murray

Paul Edwards

Drag racing invasive species buckle up and hold on tight

Patterns of dispersal of an early invader: Implications for Monitoring

University of British Columbia

Marine invaders transported by commercial and recreational vessels must undergo journeys of considerable time and distance, while enduring extreme physical conditions. Successful transportation of hull fouling species primarily depends on the ability to avoid hydrodynamic dislodgement from the vessel. We would therefore expect that highly successful hull fouling invaders would have adaptations to reduce the probability of dislodgement. Possible adaptations include behavioural modifications in flow, strong attachment, low-drag body forms and larval settlement preferences. In this study we asked the question: Are invasive species better adapted for transport than native ones? We used measurements of attachment strength and drag to estimate dislodgment

McGill University

velocity for a variety of common native and nonindigenous fouling species. Nonindigenous species not only had greater attachment strength than congeners but some also utilized reconfiguration to reduce drag. These adaptations likely contribute directly to their ability to utilize hull fouling vectors for successful introduction and spread of non-native invaders. Estimated dislodgment velocities matched well with our observations of vessel type with invasive tunicates attached. These results can be integrated into a transport model to predict future invasions based on morphological and biomechanical characteristics, thereby improving vector management strategies and identifying potentially risky species and vessel types.

28 Canadian Canadian Aquatic Aquatic Invasive Invasive Species Species Network Network Final Final Conference Conference Programme Programme 2011 2011

Invasive species are a growing problem and the ecological, financial and health impacts they cause are a new form of global change. Early detection of invasions maximizes the likelihood of treatment success, yet monitoring efforts are typically ad hoc, leading to inefficient or ineffective monitoring. Logically, focusing monitoring where the species are likely to occur maximizes probability of detection and minimizes required effort. However, this relation has not yet been formalized. Ciona intestinalis was first detected in Boughton Bay, PEI in 2007. There we documented the post-colonization spread using a grid of 85 settlement plates. Analysis shows intriguing heterogeneity that suggests multiple drivers at play. Beyond elucidating the mechanisms of early spread, analysing these patterns can address which station would have had the highest probability of detection. We can compare, for instance, if sampling the lower, middle or upper bay would have been most efficient; or if sampling only close to shore or artificial structures would be more effective. In each case, detection can be quantified and compared to random methods. In addition I present a model-driven assessment of hydrodynamic influence to establish if this improves settlement predictions beyond simple habitat modeling. If so, transport models may inform monitoring programs in similar bays in PEI and the Magdalen Islands where there is a high risk of future introductions.

Louis Ferguson

Lifei Wang

The fertility of Ciona intestinalis eggs under mussel processing plant conditions

Effects of sample size and species distribution patterns on the performance of species distribution models

Ciona intestinalis is the dominant invasive tunicate species in the Montague River estuary, Prince Edward Island and is now present in adjacent bays. The spread of this solitary tunicate in PEI, however, is not limited to larval dispersal. Removal of C. intestinalis from mussels in processing plants can lead to the release of gametes in effluent water and the subsequent fertilization of eggs in the plant or in the bay. C. intestinalis eggs are exposed to salinity, temperature, water flow, and turbidity variations within this effluent water. The two separate trials in this experimental study focused on the effect of water turbidity and water flow on C. intestinalis egg fertilization. The first trial evaluated the effect of water turbidity (0, 300, 600 and 1 200 NTU), and the second evaluated the effect of water turbidity (0, 300, 600 and 1 200 NTU) with water flow (0.9583 L/s). Unfertilized eggs were then exposed to viable sperm and incubated at 21⁰C for 48h. Total propagules (eggs, larvae and recruits) were counted under a dissecting microscope for the three repetitions in the trials. Levels of turbidity did not change the fertilization rate (65.88±2.95%). Water flow decreased fertilization rates but there was no difference between turbidity levels. The control had a mean fertilization rate of 63.14% (±1.75%), while the mean of the treatments was 50.25% (±2.85%). These trials continue to provide a clear indication of the potential propagule pressure of processing plants. Additional in situ experiments are needed to determine potential mitigation measures.

Knowledge of species’ ecological and geographic distributions is increasingly important for investigating the habitat requirements of native or introduced species, planning management programs for invasive species and conservation programs for endangered species, and understanding the essential determinants of biodiversity patterns. Detailed information on species distributions is often unavailable for some taxa or regions, and collecting such data may be costly and timeconsuming. Therefore, to determine the effects of sample size on model performance is important for making reliable predictions. It is difficult for ecologists to evaluate modeling approaches for predicting species distributions using field data because the true situation is unknown. Predictive models should be able to approximate the true relationship if ecologists want to use them as reliable tools. In our study, simulated data (known values) derived from explicit theory were used to evaluate the performance of different modeling approaches. The generalized beta function was used for describing different shapes of species

University of Prince Edward Island

University of Toronto

responses, and the true dataset was generated using it. Data with different sample sizes were randomly drawn from the true dataset and then used for developing models. Modeling approaches including linear discriminant analysis, multiple logistic regression, random forests and artificial neural networks were developed on the sampled datasets. The performance of model predictions was evaluated using the area under the receiver operating characteristic curve (AUC) and several other performance metrics. With increasing sample size, model accuracy increased and variability decreased across species response shapes and among models. Prediction success of artificial neural networks increased a lot when sample size increased, whereas random forests performed more consistently at different sample sizes. ck of a relationship between port activity and number of exotic species also suggests that eelgrass may have limited available resources for newly arrived species or that eelgrass has some other mechanism for resisting introduced species.

Quebec Quebec City, City, Quebec Quebec AprilApril 27–28, 27–28, 2011 2011


Poster Abstracts Series I

Megan Mach

University of British Columbia

Identifying exotic species in Canadian eelgrass beds at a regional and national scale

Eelgrass beds provide important structure for invertebrate communities and act as nursery grounds and shelter for many commercially important species of fin & shellfish. It is essential not only that these beds continue to exist along our coasts but that scientists fully understand threats to the species they support. Exotic species are becoming a common threat to coastal marine populations, yet little is known about what exotic species are in Canadian eelgrass beds. With human transport of exotic species via shipping as one of the most common vectors of invasion, we would expect exotic species to have greater diversity in areas where there is a greater amount of shipping traffic. To test this we sampled 18 Zostera marina eelgrass

beds on the Pacific and Atlantic coasts of Canada, 12 port sites with a gradient of shipping activity and 6 non-port sites, for infaunal, epifaunal and mobile macroinvertebrates. We used these data to compare exotic to native species diversity and abundance across varying levels of shipping activity within each coast and across coasts. In British Columbia (BC) there were 10 exotic and 6 cryptogenic species in the infaunal and epifaunal eelgrass invertebrate communities. Of the 11 eelgrass beds sampled on the BC coast, composition of exotic species in individual eelgrass beds was highly site specific and was mostly comprised of exotic arthropods and mollusks. In contrast, eelgrass beds in Nova Scotia (NS) contained only two exotic species, Littorina littorea and

30 Canadian Canadian Aquatic Aquatic Invasive Invasive Species Species Network Network Final Final Conference Conference Programme Programme 2011 2011

Carcinus maenas. These species were found at all 7 sites sampled. We found no relationship between number of ships or amount of ballast and the richness or abundance of exotic species in BC or NS. Nor did we find a relationship with native species richness, diversity or abundance. The low number of total exotic species in eelgrass in both BC and NS is surprising when considering the high level of shipping activity of some of these ports, such as Vancouver, BC and Halifax, NS. The lack of a relationship between port activity and number of exotic species also suggests that eelgrass may have limited available resources for newly arrived species or that eelgrass has some other mechanism for resisting introduced species.

Poster Abstracts Series II

Oscar Casas-Monroy

Erin Gertzen

Presence of non-indigenous dinoflagellate cysts in ballast sediments: comparison between canada’s east coast, west coast and the great lakes

Assessing the relationship between propagule pressure and probability of establishment for Bythotrephes

ISMER, Université du Québec à Rimouski

Shipping activities are believed to be primarily responsible for most introductions of non-indigenous species (NIS) in North America. To reduce the abundance/diversity of NIS, ships have to exchange their ballast water in midocean, before reaching coastal regions. However, introductions continue, even with mandatory regulation for the control of ballast water management. To understand the invasion process the present study focuses on the abundance/diversity of resting cysts of dinoflagellates and their toxic/harmful species in ballast sediments and compares the efficacy of ballast water exchange (BWE) for ships arriving to the East and West marine coasts and the Great Lakes of Canada. Most of the 147 sampled ships performed BWE using empty-refill (34%) or flow-through (31%) while only 5% used alternative method. Species richness was higher in CE ships arriving to the West coast (17), followed by CNE ships visiting the East coast (16), but quite similar in ships examined for the Great Lakes. The maximum number of taxa was recorded in samples from ships in West coast (60 taxa), while the maximum number of NIS was recorded from ballast sediments from ships entering the Great Lakes (38 taxa), out of which 6 were considered potentially harmful/toxic species. For marine regions, 14 taxa were identified as NIS and a maximum of 7 were considered as potentially harmful/toxic. Several dinocyst NIS observed here live in marine environments with relatively similar temperature/salinity conditions as local coastal ecosystems, which could facilitate their successful establishment.

McGill University

Estimating the probability of establishment of non-indigenous species is a crucial element in managing their spread. We used two approaches to estimate the probability of establishment of Bythotrephes longimanus. At a watershed level, we developed a vector based model to predict the probability of establishment of Bythotrephes over time. We used metrics of propagule pressure from anthropogenic and natural dispersal to estimate spread, and extend the model to incorporate spatial and temporal gaps in knowledge of the invasion status of lakes. We found that recreational boating traffic is the dominant vector of spread. Next, at the scale of a local population introduction, we investigated probability of establishment empirically. We followed Bythotrephes populations over their entire life cycle and looked for evidence of early invasion dynamics that

may affect establishment, including Allee effects, demographic and environmental stochasticity, windows of opportunity and bottlenecks during sexual reproduction. We found that populations introduced at low doses exhibit weak Allee effects during sexual reproduction and that these effects strengthen over the season. Further, we found evidence that populations may use adaptive sex-ratios to minimize the Allee effect. Probability of establishment was positively related to propagule pressure; however, the relation was highly stochastic. The insights obtained on the characteristics of the relation between propagule pressure and probability of establishment at population and watershed scales can be linked in management plans aimed at slowing the spread of Bythotrephes in inland lakes.

Quebec Quebec City, City, Quebec Quebec AprilApril 27–28, 27–28, 2011 2011


Poster Abstracts Series II

Patricia Pernica

Yanjun Sun

Suncica Avlijas

Barriers to mixing in Lake St. Clair

Comparisons of the Dilution Patterns of Discharged Ship Ballast Water in Goderich Harbour and in the St. Clair River

Patterns of Distribution and Abundance of Hemimysis anomala in Relation to Physico-chemical Variables

Lake St Clair is a large, shallow lake situated in between Lake Huron and Lake Erie that carries the outflow of the 3 upper Great Lakes. Lake St Clair is known to be a “hotspot” for the establishment of Aquatic Nuisance Species (ANS) within the Great Lakes, so it is of interest to know if this could be due to the circulation patterns within the lake. Empirical evidence suggests that there are significant differences in the residences times and water quality measurements in the east and west basins of Lake St Clair, therefore there may be large regions of the lake that effectively act as incubators for ANS. We seek to determine the underlying physical mechanisms that lead to the separation of the lake into to these two distinct regions. Using depth averaged 2D velocity data produced from the NOAA model (FVCOM) of Lake St Clair we identified dynamically different regions of the flow termed Lagrangian Coherent Structures (LCSs) for the week of July 17th to July 23rd 2009. Boundaries of LCSs indicate barriers to fluid mixing and the existence of a persistent LCS transport barrier between the east and west basin is observed even with changes in wind speed and direction. Numerical particle trajectories are compared with 9 GPS track drifters released during the same time period as part of a ballast water dye release study. Comparison demonstrates fairly good agreement between the field experiment and the numerical simulation, and suggests that LCS could be used a tool to determine the best locations for ballast water release.

The physical dilution patterns of ballast water discharged from freight ships in the Great Lakes influence the process of biological invasions. An aquatic population can be written as: ∂D/∂t = physical dilution rate + net biological growth rate (D: the population density; t: time). Two field experiments were conducted in 2008 and 2009 to determine the potential range of dilution rates that might occur at typical ballast water discharge sites within the Great Lakes. The sheltered Goderich Harbour on Lake Huron can be an example site that is expected to have low dilution rates, while the St. Clair River is expected to have high dilution rates. The observed dilution patterns in the river and harbour can be divided into different stages. During the initial stage the strongest dilution of ballast water occurs due to mixing in the discharge jet. In the following stages the ballast water is diluted due to the river dispersion or harbour flushing. The peak tracer concentration decayed with an exponential rate beyond the initial stage. The decay rate in the river (over 10 day-1) is much higher than in the harbour (about 1 day-1). The decay rate observed in the harbour is comparable to some maximum growth rates rmax of zooplankton (0.1~1 day1). We suggest that management of ballast water discharge into the Great Lakes should pay more attention to the discharge into harbours that are subject to limited flushing or long residence time, whereas lower risk is associated with discharge into fast flowing rivers.

The bloody red mysid Hemimysis anomala, a Ponto-Caspian crustacean, is expanding its range in the Great Lakes – St. Lawrence River basin. Negative impacts associated with introductions of mysid species to North American and European lakes raise concerns about the potential ecological consequences of this invasion. Useful risk assessments require a predictive understanding of habitat conditions that support dense local populations of the mysid. However, large gaps exist in current knowledge of the relative importance of different habitat variables for H. anomala’s establishment and proliferation. To address this need, data were collected through nearshore field surveys in Lake Ontario in 2009 and the St. Lawrence River in 2010, targeting a diverse suite of sites at two spatial scales: 1.5km wide sites and 10m wide nested subsites. Mysid populations were found across sites in Lake Ontario and the upper St. Lawrence River at densities spanning more than 3 orders of magnitude. We related the mysid’s local occurrence and abundance to physico-chemical variables (selected based on European studies suggesting their importance) including water conductivity, water discharge, shoreline heterogeneity and macrophyte cover at the site scale, and sediment size, local flow and shoreline slope at the sub-site scale. The resulting predictive models will be presented. Such models are valuable for planning future surveys for H. anomala and for anticipating and prioritizing invaded habitats for management.

University of Toronto

University of Toronto

32 Canadian Canadian Aquatic Aquatic Invasive Invasive Species Species Network Network Final Final Conference Conference Programme Programme 2011 2011

Redpath Museum, McGill University

Abisola Adebayo

Natalie Kim

Domestic Ballast as a Potential Vector for the Introduction of Nonindigenous Species in the Great Lakes – St. Lawrence River

Impacts of prey quantity and quality on Bythotrephes reared in the laboratory

Great Lakes ports receive approximately equal amounts of transoceanic and domestic (St. Lawrence River – SLR) ballast. While transoceanic ballast is recognized as a historically important introduction vector of NIS to the Great Lakes and is now well managed by ballast water exchange regulations, domestic ballast is generally considered to be lower risk and is currently unregulated. Here we examine the potential risk of ballast from the SLR as a vector of NIS to the Great Lakes. We conducted biological surveys at 6 Great Lakes’ ports, 16 SLR ports, and sampled ballast water of 29 vessels with transits originating from SLR ports. We compare the invertebrate communities and environmental similarity between SLR and Great Lakes ports and estimate colonization and combined propagule pressure to the Great Lakes. Species level identification is currently underway; to date, 1 NIS (Microsetella norvegica) found in samples to date has not been reported from the Great Lakes. The comparative invasion risk posed by ballast moved from SLR ports to the Great Lakes will be discussed.

The invasive crustacean zooplankter Bythotrephes longimanus (herein Bythotrephes) continues to spread rapidly across lakes of the Canadian Shield. Through laboratory bioassays, we consider the possible influences of both prey quantity and quality on a variety of Bythotrephes life table metrics. First, we reared Bythotrephes neonates under low (15 prey d-1), medium (30 prey d-1) or high (45 prey d-1) food levels, consisting of assorted prey species. As expected, intrinsic rates of natural increase and net reproductive rates rose with increasing prey abundance, while cohort generation times fell. Next, batches of the green alga Scenedesmus obliquus were enriched with the essential omega-3 fatty acid, eicosapentaenoic acid (20:5(n-3)). Daphnia cultures were then reared on non-enriched or enriched algae, and offered as prey

GLIER, University of Windsor

York University

to Bythotrephes. Daphniids reared on enriched algae were significantly larger than animals reared on non-enriched algae. Perhaps as a consequence of this, the mean feeding rate of young Bythotrephes on “enriched” daphniids was significantly lower than those feeding on “non-enriched” daphniids. By day 11 however, Bythotrephes reared on the enriched diet had a significantly higher number of eggs or embryos in their broodsacs than those maintained on the non-enriched diet. Our findings suggest that prey availability in terms of both quantity and quality may be critical for Bythotrephes establishment success in the field. While high food quality may confer an escape advantage to prey from young Bythotrephes, the availability of a single fatty acid, EPA, can potentially have vast repercussions on Bythotrephes population growth rates.

Quebec Quebec City, City, Quebec Quebec AprilApril 27–28, 27–28, 2011 2011


Poster Abstracts Series II

Olivia Lacasse

Corey Chivers

Is there a link between dinoflagellate cyst assemblages and shipping traffic in Nova Scotia?

Modeling responses to management intervention in the control of spread of freshwater invasives

ISMER, Université du Québec à Rimouski

The impacts of introduced marine organisms are numerous, they can either be economical, ecological or even public health related. With their ability to produce Harmful Algal Blooms (HAB), dinoflagellates represent a serious threat because they can impact all three sectors mentioned above. Because of the potential threat these organisms represent it is important to monitor their introduction but before knowing if a new species has been introduced, we need to document their present occurrence in a given environment. Therefore, this study focuses on identifying the dinoflagellate cyst (dinocyst) assemblages found in the sedimentary deposits of selected East coast Canadian ports. Samples were collected in triplicate in July 2008 from six sites in eight ports in Nova

McGill University

Scotia. Samples were sieved on 100 and 20 µm mesh size Nytex membranes and the >20 µm fraction was analysed with an inverted microscope. Results show that there are three distinct groups of dinocyst assemblages. The average concentrations range from 1346 to 83 351 cysts/g dry sed and the species richness index ranges from 14 to 40. The distribution of the dinocyst assemblages within a given port is quite homogeneous. Statistical analysis indicate that there is a positive influence of the number of ships on the concentrations of dinoflagellate cysts (Mean cyst conc. = 3188.07 + 71.7*Number of ships; r2 = 0.83; ANOVA model: F1,6 = 29.46; p = 0.0016). This study constitutes the first attempt to demonstrate the link between shipping and the dinocyst concentrations.

34 Canadian Canadian Aquatic Aquatic Invasive Invasive Species Species Network Network Final Final Conference Conference Programme Programme 2011 2011

Several freshwater aquatic invaders have been found to spread between inland lakes primarily via overland dispersal mediated by recreational boaters. In the interest of mitigating further spread, management actions such as the inclusion of mandatory boat hull cleaning stations has been proposed. The implementation of any locationspecific management strategy such as hull cleaning at specific boat launches imposes an additional factor which may influence recreational boaters’ decision to use a given lake. As such, in addition to the per boat reduction in propagules that such a management action would achieve, the behavioural consequences of management must also be considered. We conducted an online survey of recreational boaters (n=580 respondents, t=2354 boating trips) in Ontario in order to assess how boater behaviour might change under location-specific management strategies. By building on the concept of gravity models, we integrate boaters’ behavioural feedbacks to management actions and test the efficacy of various scenarios. Our results suggest that the efficacy of location-specific management actions can be either positive or negative depending on the timing and configuration of the strategies.

Closing Banquet Jean Paul Lemieux Room Le Concorde Lower Level Thursday, April 28, 2011 6:30 pm

We invite you to come celebrate and close CAISN’s Final Conference with a dinner banquet held in the Jean-Paul Lemieux Room beginning at 6:30 p.m. Dr. Warwick Vincent will inspire us with his talk entitled, “Our rapidly changing polar regions: Earth’s final frontier for invasive species”. Poster Award Winners will also be announced.

Lower Level

Quebec Quebec City, City, Quebec Quebec AprilApril 27–28, 27–28, 2011 2011