1. Human-mediated and natural dispersal of invasive species: implications for watershed- scale management practices Thomas Horvath Biology Department State University New York College at Oneonta

2. Linkages: Lentic-lotic links Human-invasive species links

3. Weekly World News, August 1993

4. “Non-native species cause $123 to 137 billion in damage annually – more than twice the annual economic damage caused by all natural disasters in the US.” D. Pimentel 24 Jan, 1999 AAAS

5. Source: Precious Heritage: The Status of Biodiversity in the United States © The Nature Conservancy and NatureServe 100 80 60 40 20 0 Habitat Degradation/ Loss Exotic/ Invasive Species Pollution Overexploitation Disease %Species Affected by Cause (n=1,880)

6. “Invasive species and their environmental damage are the most irreversible form of pollution.” David Lodge Chair, National Invasive Species Advisory Committee

7. Dreissena polymorpha (Pallas)

8. Economic Impacts

9. Ecological Impacts Direct impact on native Bivalves

10. Freshwater Mussel Diversity Family Unionidae

11. Source: Precious Heritage: The Status of Biodiversity in the United States © The Nature Conservancy and NatureServe Freshwater Mussels Crayfishes Amphibians Fishes Flowering Plants Conifers Freshwater Butterflies/ Damselflies Ferns Reptiles Dragonflies/ Tiger Beetles Skippers Mammals Birds Critically Imperiled Presumably/ Possibly Extinct Imperiled Vulnerable 0%10%20%30%40%50%60%70% Proportion of Freshwater Dependent U.S. Species at Risk

12. Dispersal Mechanisms

13. Adult mussel Veliger Lentic – Lotic Linkages

14. Passive Dispersal

15. Distance from Lake-Outlet (km) Veligers L -1 2003 02468 0 2 4 6 8 10 12 14 16 2004 02468 0 1 2 3 4 5 Eaton Brook

16. Distance from Lake-Outlet (km) Veligers L -1 2003 0510152025 0 2 4 6 2004 0510152025 0 2 4 6 Oaks Creek

17. Eaton Brook Distance from Lake-Outlet (km) Veligers (millions day -1 ) 02468 0 20 40 60 80 100 120 Oaks Creek 0510152025 0 200 400 600 800 1000 1200 1400 1600 1800 Veliger Flux (2003)

19. Linkages due to Human Behaviors

20. Boater Survey Results Eaton Brook Reservoir Estimated 1635 recreational visits to EBR 98% of boaters have heard of zebra mussels 32% of boaters don’t know how to prevent the spread of zebra mussels 224 survey points 126 interviews

21. Boater Survey Results Eaton Brook Reservoir 55 boaters had used their boat in a nearby ZM lake within past week 20% of all boaters were moving to another non-ZM lake within a week

22. Boater Survey Results Eaton Brook Reservoir 14% of boaters had aquatic plants on their boat after as they were leaving 6% of boaters had live zebra mussels on their boats

23. Boater Survey Results Eaton Brook Reservoir 14% of boaters had aquatic plants on their boat after as they were leaving 6% of boaters had zebra mussels on their boats 1635 boat trips x 6% w/ zm ≈ 100 boaters transporting live zebra mussels in 2004

25. What Can We Do?

26. Zebra Mussels (Dreissena polymorpha) in the Chesapeake Bay Watershed: A Regional Management Plan Goals 1.Stop the further spread of zebra mussels by identifying strategies and partnerships necessary to control the spread of mussels 2.Eradicate zebra mussel colonies in the Chesapeake Bay watershed where possible Chesapeake Bay Program

27. Invasive species management plans recommends: public outreach programs monitoring programs rapid response strategies possible eradication methods actions and funding needs to implement each of the recommendations

28. Kolar & Lodge 2001 Species entrained in transport pathway Survives transport & introduction Establishment SpreadSpread Fails in transport Fails in establishment Noninvasive Invasive Preventive Mgt Actions

29. Otsego Lake Cooperstown, NY

31. Ending Thoughts Lakes serve as sources for further invasions Models suggest the “stitch in time” approach makes sense

32. Policy makers should be informed of the benefits of prevention programs from the standpoint of both reducing species invasions other than the targeted species, as well as the economic benefits associated with avoiding potential future direct and indirect costs of unchecked invasion, control, or elimination. Horvath. 2008. Economically viable strategy for prevention of invasive species introduction: Case study of Otsego Lake, New York. Invasive Species 3(1): 3-9.

33. Thank You horvattg@oneonta.edu Shameless Advertisement: We are looking for a Professor of Lake Management See me for details.