Aquatic Redpath Museum McGill University

This presentation was made possible with funding from the PromoScience programme of NSERC

www.wikipedia.org: public domain or licensed under a Creative Commons Attribution Share-Alike 3.0 License

©McGill University 2011 One of these things is not like the others…

www.wikipedia.org: licensed under a www.wikipedia.org. Public domain. Creative Commons Attribution-Share Alike 3.0 Unported license.

www.wikipedia.org: licensed under a www.wikipedia.org: USDA, public domain Creative Commons Attribution-Share Alike 3.0 Unported license. ©McGill University 2011 A very different beast

• mussels are not native to Canada: they are an invasive species

www.wikipedia.org: licensed under a Creative Commons Attribution-Share Alike 3.0 Unported license. ©McGill University 2011 What is an invasive species?

• An invasive species is a species that: – is not originally from an area (i.e., it is not a species native to that area)

– may threaten the environment, the economy, or society including human health in the new area to which it is introduced or spreads. ̶ ̶ • An invasive species can be an , plant, fungus, bacteria, or virus.

©McGill University 2011 Aquatic invasives • Aquatic invasives live in aquatic environments. • Some species live only in fresh water, others live only in salt water, and some species can tolerate both fresh and salt water, Chinese mitten crab: enabling them to spread an invasive species that can tolerate a range of salinities throughout many different but needs salt water to ecosystems. reproduce www.wikipedia.org: Creative Commons Attribution-Share Alike 3.0 Unported license. ©McGill University 2011 How do invasives harm the environment? (i) • Without native predators and parasites to control them, invasive species often flourish.

Zebra mussels covering a current meter.

www.wikipedia.org: public domain ©McGill University 2011 How do invasives harm the environment? (ii)

• In their new ecosystems, invasive species may become • predators • competitors • parasites

• diseases Sea lampreys attached to a lake trout of our native and domesticated plants and .

www.wikipediia.org: USGS, public domain. ©McGill University 2011 Aquatic invasives: mussels (i) • Invasive species can change habitat and make it inhospitable for some native species. • E.g., Zebra mussels in the filter tremendous amounts of plankton out of the water: • The water is clearer • Sunlight penetrates deeper • There can be overgrowth of vegetation and toxic algal blooms • There can be less plankton available for native plankton-feeders (e.g., other invertebrates, www.wikipedia.org. Public domain. fish), that now have to compete for food ©McGill University 2011 Aquatic invasives: mussels (ii)

• Zebra mussels and one of the newer invaders, the mussel, have wiped out most of the native mussel populations in the Saint-Lawrence River, changing the invertebrate populations in ways that scientists are still studying.

Native mussels (Lampsilis sp.) Native mussel (Lampsilis sp.) covered with zebra mussels. www.wikipedia.org. Public domain. Photo credit: A. Ricciardi. ©McGill University 2011 Aquatic invasives: mussels (iii)

• In a strange twist that pits invasive vs. invasive, the quagga mussel may now be out-competing the ! • In some areas of the St. Lawrence and most of the Great Lakes, the quagga mussel has replaced the zebra mussel as the dominant bivalve.

Zebra mussel www.wikipedia.org. Public domain. Quagga mussel ©McGill University 2011 Aquatic invasives: fish

• Invasive species can prey on native species, including species at risk, and threaten their survival. This reduces biodiversity. • For example, the is a bottom-feeder that preys on local invertebrates that feed native fish species. The round goby also eats fish eggs.

Round goby

www.wikipedia.org. Public domain. ©McGill University 2011 Aquatic invasives: shrimp

• Bloody red mysid shrimp (Hemimysis anomala) were found in the Great Lakes in 2006 and are spreading throughout the St. Lawrence river. • There are no native freshwater shrimp in North American rivers. When an invasive has no equivalent in the environment it is invading, the impact it has is more likely to be an important one.

NOAA, Great Lakes Environmental Research Laboratory. www.wikipedia.org. Public domain.

©McGill University 2011 Invasives and disease (i)

• Viral Hemorrhagic Septicemia (VHS) virus is an invasive species that affects over 100 species of fish, including muskellunge, northern pike, , walleye, and smallmouth bass. Photo credit: Dr. Mohamed Faisal, Michigan State University. Accessed at http://www.nps.gov/piro/naturescience/vhs.htm • VHS has been present in the Great Lakes- St. Lawrence system since 2003 or earlier, and it has caused several fish die-offs in the Great Lakes and upper St. Lawrence River. Die-offs have not yet been recorded in Quebec waters.

©McGill University 2011 Invasives and disease (ii)

• VHS was probably introduced to the Great Lakes- St. Lawrence system from the Atlantic coast of North America, but it is not known how it was introduced.

• For more information, please see this VHS factsheet.

Photo credit: Dr. Mohamed Faisal, Michigan State University. Wikipedia.org. Public domain.

©McGill University 2011 Invasives and biodiversity

• In freshwater systems, invasive species are the second most significant threat to biodiversity, after habitat loss! • On average, a new invasive species is discovered in the Great Lakes every 28 weeks. That suggests the highest rate of invasion known for any freshwater system.1

1Ricciardi, A. 2006. Patterns of invasion in the Laurentian Great Lakes in relation to changes in vector activity. Diversity and Distributions 12: 425-433

©McGill University 2011 Do invasive species have only negative effects? (i) • Nearly all invaders have both positive and negative effects.

• Even those invasive species that produce strong negative impacts can also produce strong positive ones, depending on the ecosystem component you are considering.

©McGill University 2011 Do invasive species have only negative effects? (ii) • For example, the increased water clarity generated by zebra mussels benefits submerged aquatic plants, the invertebrates that live on them, and the fish that use weedy habitats. • However, because we do not know what impact any invader will have, it is best to prevent the entry and spread of invasive species right from the start.

©McGill University 2011 How do aquatic invasive species get to Canada? • In the ballast water of ships • Snagged on recreational boats • As live bait, aquarium fish, and exotic pets released into our water bodies

www.wikipedia.org. Public domain or Creative Commons Attribution-Share Alike 3.0 Unported license.. ©McGill University 2011 The trouble with ballast (i)

• Large ships coming from freshwater ports in Europe and Asia used to release ballast water they picked up at home into the Great Lakes.

• This meant that any species present in that water could have been released into the Great Lakes as well.

www.wikipedia.org. Creative Commons Attribution-Share Alike 3.0 Unported license. . ©McGill University 2011 The trouble with ballast (ii)

• Invasive species have been introduced to the Great Lakes by ballast water release since the early 20th century. This trend increased greatly after the St. Lawrence Seaway opened in 1959.

Many of the invasive species currently in the St. Lawrence River spread there following ballast water introductions in the Great Lakes.

www.wikipedia.org. Creative Commons Attribution-Share Alike 3.0 Unported license. . ©McGill University 2011 Ballast water blacklisted • In 1990, new guidelines from the Canadian government were put in place. These guidelines meant that ships were no longer allowed to exchange freshwater ballast in lakes, rivers, etc. Instead, ships had to release all of their ballast water in the ocean before entering the river. They would then take on salt water as ballast.

• In 2008, a loophole that still allowed certain ships to exchange ballast water in freshwater lakes, rivers, etc. was closed. Since then, scientists have not been able to attribute any new invaders to ballast water.2, 3

2 Ricciardi, A. 2006. Patterns of invasion in the Laurentian Great Lakes in relation to changes in vector activity. Diversity and Distributions 12: 425-433 3 Ricciardi, A. and MacIsaac, HJ. 2008. Evaluating the effectiveness of ballast water exchange policy in the Great Lakes. Ecological Applications 18(5): 1321–1323 ©McGill University 2011 Everyone’s problem

• Aquatic invasives affect everyone using our waters: – fishing industries – boaters – anglers and harvesters – divers – cottage owners – municipalities

©McGill University 2011 How you can help

• Thoroughly wash your boat and all gear, including waders, after use

• Remove all aquatic plants and animals from boats and gear

• Drain water from your boat, trailer, tackle, and gear before leaving an area

• Do not release aquarium pets, plants, or live bait into aquatic environments

• Do not move live fish and other aquatic organisms from one body of water to another.

From: Fisheries and Oceans Canada, www.dfo-mpo.gc.ca

©McGill University 2011 More information

• Aquatic invasive species: Fisheries and Oceans Canada • Aquatic Invasive Species Identification Booklet: Fisheries and Oceans Canada • Battle for the Riverbed: Montreal Gazette • Invasive Species Fact Sheets: Dr. A. Ricciardi, Redpath Museum, McGill University

©McGill University 2011 Acknowledgements

• Scientific consultation: Dr. Anthony Ricciardi, Redpath Museum • Concept, design, and production: Jacky Farrell, Redpath Museum

This presentation was made possible with funding from the PromoScience programme of NSERC

©McGill University 2011