1. Control of Aquatic Invasive Species and Restoration of Natural Communities in Ireland Dr Joe Caffrey Central Fisheries Board QUB, Belfast – 7 th April 2009

2. Scope High impact aquatic invasive species in Ireland Case studyLagarosiphon major (Curly Waterweed) Future work and funding

3. High Impact Aquatic Invasive Species Curly WaterweedLagarosiphon major Nuttall’s WaterweedElodea nuttallii DaceLeuciscus leuciscus Zebra MusselDreissena polymorpha New Zealand PigmyweedCrassula helmsii Parrot FeatherMyriophyllum aquaticum Fringed Water lilyNymphoides peltata Water FernAzolla filiculoides

4. Chinese Mitten CrabEriocheir sinensis ChubLeuciscus cephalus Bloody Red ShrimpHemimysis anomala Floating PennywortHydrocotyle ranunculoides Potentially High Impact Aquatic Invasive Species

5. Lagarosiphon near Kilmeaden, Waterford 2005

6. Nuttall’s Waterweed (Elodea nuttallii) in Carrigadrohid Reservoir

7. New Zealand Pigmyweed (Crassula helmsii) Emergent and submerged

8. Parrot’s Feather (Myriophyllum aquaticum)

10. Fringed Water lily (Nymphoides peltata)

11. Water Fern (Azolla filiculoides)

12. Azolla in River Barrow and Limerick Canal

13. Chinese Mitten Crab (Eriocheir sinensis) - 2005

14. Chub (Leuciscus leuciscus), River Inny – 2006

15. Bloody Red Shrimp (Hemimysis anomala) Photo - Dan Minchin (2008)

16. Floating Pennywort (Hydrocotyle ranunculoides)

17. Case Study Lagarosiphon major in Lough Corrib INVASIVE SPECIES CONTROL

18. Curly Waterweed (Lagarosiphon major) Submerged aquatic ‘Oxygenating weed’ Artificial watercourses ~ Only natural habitat is Lough Corrib

19. Rinerroon Bay, Lough Corrib pre-Lagarosiphon major

20. Rinerroon Bay, Lough Corrib post-Lagarosiphon major (2005)

22. Why is Lagarosiphon a Problem? No natural enemies in Ireland Rapid growth rate Dispersal through fragmentation Actively grows in winter Canopy forming – excludes indigenous macrophytes Alters macroinvertebrate community structure Creates improved conditions for coarse fish No legislation to prohibit its sale and distribution

23. Lagarosiphon Control Methods Currently Employed Hand removal using Scuba Mechanical cutting and harvesting Herbicides Light exclusion Life cycle studies [Biological control]

24. Hand Removal using Scuba Lagarosiphon in low abundance - recently colonised sites - edge of large stands - following other treatment methods

25. Herbicides for Lagarosiphon Control Lough Corrib is a SAC and drinking water supply !!! Only one approved herbicide to treat submerged weeds Lagarosiphon is susceptible to dichlobenil Applied locally in upper lake

26. Mechanical Cutting in Lough Corrib Deep cut with trailing knives (V-blades) 10 infested sites treated in 2008 4,700 tonnes of Lagarosiphon removed 29.2 hectares of infested lake bed cleared

27. Light Exclusion using Biodegradable Geotextile - 2008 Trials commenced in August 2008 1,750 sq m at 4 sites treated Early indications positive

28. Little is known about the life cycle strategies or adventive traits of Lagarosiphon under Irish conditions Life Cycle Studies as an Aid to Lagarosiphon Control Less is known about the factors that influence its growth in Irish waters This information is vital if potential weak links in Lagarosiphon’s life cycle are to be identified and targeted for specific control

29. Restoration of Natural Communities Natural recolonisation of indigenous species from spores, seeds, fragments Transplant indigenous species Create conditions favourable for indigenous species

30. Funding & Future Research Primary source of funding for 2009 - 2013 is Life+ (EU & NPWS) €1.5 million 2 Projects Lagarosiphon control in Lough Corrib Invasive species in Grand Canal / Barrow corridor Worth approx. €180k per annum per project (vs c. €200k for 6 months on Lagarosiphon in 2008)

31. Strategic Control of Lagarosiphon in 2009 Clearance of sites from all upstream sites

32. Strategic Control of Lagarosiphon in 2009 Mechanical cutting of sites on north-western shore

33. Strategic Control of Lagarosiphon in 2009 Apply geotextile to all sites in the middle lake

34. Road Map for Lagarosiphon Control in Lough Corrib

35. Biocontrol PhD to be funded – commencing in summer 2009 Collaboration with University of Grahamstown in SA No. of candidate species already identified Photos J-R Baars

36. Can We Eradicate Lagarosiphon in Lough Corrib? Enormous task – using traditional methods Best expertise available will be utilised Biocontrol may provide the ‘silver bullet’