Invasive Species in Great Lakes: Zebra Mussels by M.Foster
Great lakes facts   <ul><li>Great Lakes  -  hold 20 % of the world’s fresh water and 95 %  of North America’s surface wate...
Zebra Mussels Invasion <ul><li>Zebra mussels first appeared in North America in 1988 in Lake St. Clair (btw.Lake Huron & E...
Zebra Mussels Spread <ul><li>Invasives that enter the Great Lakes can then spread across the continent through river syste...
 
 
Further Spread <ul><li>Larvae spreads via water currents, fishing activities, recreational sports; </li></ul><ul><li>Adult...
What are Zebra Mussels? <ul><li>Dreissena Polymorpha  is a species of small freshwater mussel, an aquatic bivalve mollusk,...
What are Zebra Mussels? <ul><li>Max length - 2 inches;  </li></ul><ul><li>Life span of between 2-5 years; </li></ul><ul><l...
 
“ Life Style” & Predators <ul><li>Filter-feeding organisms: remove particles from the water, increasing water clarity and ...
Biological & Ecological Impacts <ul><li>Swimming areas become abandoned due to sharp-edged shells washing up from storms; ...
Crayfish populated  with zebra mussels
Biological & Ecological Impacts <ul><li>Zebra mussels may present a health hazard by increasing human and wildlife exposur...
Residential, Industrial and Recreational Impacts <ul><li>Zebra mussels can harm almost every aspect of water and related r...
Electrical conductor  (Lake Michigan)
Eradication issues <ul><li>Many chemicals kill zebra mussels, but these exotics are so tolerant and tough that everything ...
Eradication issues <ul><li>Controlled methods: preoxidize water at the point of intake, chemical treatments, mechanical co...
New Research Projects <ul><li>Improvement of optical techniques for mussel veligers detection </li></ul><ul><li>Veliger en...
Pseudomonas fluorescens <ul><li>It is a common soil bacteria found everywhere but harmless to humans;  </li></ul><ul><li>O...
 
Conclusion <ul><li>Effective  Monitoring : earliest possible detection of new infestations for successfully planning and d...
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Invasives

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Invasives

  1. 1. Invasive Species in Great Lakes: Zebra Mussels by M.Foster
  2. 2. Great lakes facts <ul><li>Great Lakes - hold 20 % of the world’s fresh water and 95 % of North America’s surface water; </li></ul><ul><li>The 37 million people who live in the Great Lakes Area depend on this freshwater resource for: food, water, jobs & industry; </li></ul><ul><li>The Great Lakes are one of the most invaded aquatic systems in the world, after San Francisco Bay. More than 180 different introduced species have been identified and 1-2 new species/year; </li></ul><ul><li>US alone, aquatic invasives are estimated to cost more than $73 billion/year ( $5 billion Zebra Mus.) </li></ul>
  3. 3. Zebra Mussels Invasion <ul><li>Zebra mussels first appeared in North America in 1988 in Lake St. Clair (btw.Lake Huron & Erie) </li></ul><ul><li>Mode of introduction : via ballast water or on ancors & chains; </li></ul><ul><li>Zebra mussels can survive out of water several days/weeks; </li></ul>
  4. 4. Zebra Mussels Spread <ul><li>Invasives that enter the Great Lakes can then spread across the continent through river systems such as the Mississippi to the western US; </li></ul><ul><li>North America is now going through a second major expansion of these mussels, following their establishment in the Colorado River systems; </li></ul><ul><li>In early 2008, larval zebra mussels were confirmed to be present in Pueblo Reservoir, Colorado, and adult zebra mussels were found in San Justo Reservoir, California; </li></ul>
  5. 7. Further Spread <ul><li>Larvae spreads via water currents, fishing activities, recreational sports; </li></ul><ul><li>Adult Zebra Mussels can further spread from one body of water to another by attaching to organisms (crayfish) or boats; </li></ul><ul><li>Scientists predicts that the zebra mussel will continue spreading passively, to more rivers in North America </li></ul>
  6. 8. What are Zebra Mussels? <ul><li>Dreissena Polymorpha is a species of small freshwater mussel, an aquatic bivalve mollusk, triangular in shape with an obvious ridge; </li></ul><ul><li>Zebra mussels get their name from the striped pattern of their shells; </li></ul>
  7. 9. What are Zebra Mussels? <ul><li>Max length - 2 inches; </li></ul><ul><li>Life span of between 2-5 years; </li></ul><ul><li>Preferred T - 68 and 77 o F; Depths 6-24 ft; </li></ul><ul><li>Prolifiration: 30,000 – 1 million eggs/year, - (most reproductive species: in 1m 2 Zebra Mussel populations jumped fm 1000 to 700 000 in 6 month; Only 2 - 5% adulthood; </li></ul><ul><li>By filtering 1 litre of water/day: there are now enough Zebra Mussels in Lake Erie to filter the entire volume/week; </li></ul>
  8. 11. “ Life Style” & Predators <ul><li>Filter-feeding organisms: remove particles from the water, increasing water clarity and reducing pollution: particles are consumed as food, and feces are deposited; </li></ul><ul><li>This biomass becomes available to bottom feeding species & to the fish; </li></ul><ul><li>Zebra mussels have high nutritional value & consumed in large quantities by crayfish, waterfowl & muskrats: crayfish consumes ~105 zebra mussels/day; </li></ul>
  9. 12. Biological & Ecological Impacts <ul><li>Swimming areas become abandoned due to sharp-edged shells washing up from storms; </li></ul><ul><li>Threat to Other Species: can wipe out whole populations of fish by eating all the plankton; </li></ul><ul><li>May contain high concentrations of toxic materials that will harm or kill fish & wildlife; </li></ul><ul><li>Interfering with their feeding, growth, movement, respiration, and reproduction; </li></ul>
  10. 13. Crayfish populated with zebra mussels
  11. 14. Biological & Ecological Impacts <ul><li>Zebra mussels may present a health hazard by increasing human and wildlife exposure to organic pollutants: PCB & PAH; </li></ul><ul><li>Pollutants accumulated in 300,000 times greater than in the environment; </li></ul><ul><li>Passing pollutants up the food chain; </li></ul><ul><li>Possible source of avian botulism that has killed tens of thousands of birds in the Great Lakes since the late 1990s; </li></ul>
  12. 15. Residential, Industrial and Recreational Impacts <ul><li>Zebra mussels can harm almost every aspect of water and related resources: </li></ul><ul><li>block water treatment plant intakes and pipes; restrict water flow; </li></ul><ul><li>Navigation hazards: attach themselves to boats, ropes or anything else in the water; </li></ul><ul><li>damage boat engine cooling systems; </li></ul><ul><li>Increase corrosion of cast iron pipes; </li></ul>
  13. 16. Electrical conductor (Lake Michigan)
  14. 17. Eradication issues <ul><li>Many chemicals kill zebra mussels, but these exotics are so tolerant and tough that everything in the water would have to be poisoned first; </li></ul><ul><li>Cost of dealing varies widely, depending on the type of facility, the length of infestation, and the control methods chosen; </li></ul><ul><li>For many plants, average costs hundreds of thousands of $ per year; </li></ul>
  15. 18. Eradication issues <ul><li>Controlled methods: preoxidize water at the point of intake, chemical treatments, mechanical controls, & filtration. </li></ul><ul><li>Physical barriers and chemical coatings are used to prevent zebra mussels from attaching to structures. </li></ul><ul><li>Removal: with mechanical scrapers, hot water, air, chemicals, and sound; new methods are constantly under investigation. </li></ul>
  16. 19. New Research Projects <ul><li>Improvement of optical techniques for mussel veligers detection </li></ul><ul><li>Veliger enumeration method validation </li></ul><ul><li>Early detection of Zebra mussels using PCR </li></ul><ul><li>Evaluation of filtration for excluding Zebra mussel veligers from cooling water systems </li></ul><ul><li>Evaluation of ultraviolet (UV) treatment to prevent mussel settlement in water systems </li></ul><ul><li>Field trials to demonstrate control of Zebra mussels using Pseudomonas fluorescens </li></ul><ul><li>Coatings evaluations to prevent or minimize mussel attachment </li></ul><ul><li>Fish screening technologies to reduce impacts of Zebra mussels at screened diversions </li></ul><ul><li>Controlling Zebra mussels with natural predators </li></ul><ul><li>Mussel control using copper-ion generators </li></ul><ul><li>Effects and spread of Zebra mussels in rivers and streams </li></ul>
  17. 20. Pseudomonas fluorescens <ul><li>It is a common soil bacteria found everywhere but harmless to humans; </li></ul><ul><li>Ontario’s Ministry of the Environment has approved the one-year pilot project, which could ultimately make the product legally available to other industries: 170-megawatt power stations on Twelve Mile Creek in St. Catharines was identified as a first field trial site in Canada to test chemical-free zebra mussel killer Pseudomonas fluorescens; </li></ul>
  18. 22. Conclusion <ul><li>Effective Monitoring : earliest possible detection of new infestations for successfully planning and deploying effective control strategies </li></ul><ul><li>Control solutions: proactive (excluding mussel from critical water systems) or reactive (remove from water systems after they settle) </li></ul><ul><li>Ecological impacts understanding: a wealth of experience in the Great Lakes region over the last decade has demonstrated that zebra mussels infestations create significant long-term ecological changes. </li></ul>

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