Prevention is better than cure. The case for aquatic invasive species control

Rory Sheehan, Dr. Frances Lucy, Dr. Joe Caffrey

Centre for Environmental Research Innovation and Sustainability, (CERIS), IT Sligo

• Impacts of invasions

• The cure

• Dredging of Corbicula

• Prevention

• Angler risk scoring

• Conclusion

Introduction

• Biotic homogenisation (Olden, 2006)

• Modern rates of invasion are high (Ricciardi, 2006)

• Some question Invasion biology (Davis et al., 2011)

• The field of invasion biology playing an increasingly important role (Lucy & Panov 2014; Simberloff et al., 2013)

The impacts

• Eradication and control measures

• Some have been successful

• Some have been mixed

• Some have failed

• All have high costs

• With potential for further impacts

• Intermediate Disturbance

• Benefits R strategists like Corbicula

The cure

Joe Caffrey

Joe Caffrey

• Curly leaved waterweed Lagarosiphon major

• Matting used

• Controls and remediates

• Chub Leuciscus cephalus

• River Inny

• Electrofishing used

The success stories

Graph reproduced from the CAISIE project. caisie.ie

Photo from IFI website

• Lake Tahoe Corbicula (Wittmann et al., 2012)

• Suction dredging and benthic barriers in two studies

• Non-target species reduced, over one year later

• Reduced Corbicula over one year later

• $1.4 million as of 2011 for localised hotspots

• Asian clam in Lake George

• $1.5 million for 2011 – 2012 (2013 Report)

Mixed results

Brant Allen, UC Davis.

Lake George Asian clam project

• River Barrow (Sheehan et al., 2014)

• Three differing dredges

• Box, Electric, Hydraulic

• Significant reduction in clam numbers and biomass

Dredging

Biomass Abundance

• Reducing propagule pressure

• Dangers of multiple introductions (Roman and Darling 2007)

• Targeted dredging is a useful tool but not a panacea

• Areas with high human contact

• Directing resources

• Risk scoring of angling type

• Biosecurity

• New EU Regulation

• ((EU) No 1143/2014)

Prevention

Risk score scoring

Informed direction of resources

Risk score

Angling type

Angling frequency

General population

Distance travelled

Nationality

Equipment useBiosecurity

practices

World Pairs match anglers

Angling Variable Risk Breakdown Risk Points

Angling Frequency > Once a week 100 Once a week 80 Once a fortnight 60 Once a month 40 Once a year or less 20 Average distance travelled per trip 100km or greater 100 50 – 100 km 80 20 – 50 km 60 10 – 20 km 40 10km or less 20 Total catchments visited (Ireland and international) 6 100 5 83 4 67 3 50 2 33 1 17 Number of items of equipment 12 100 11 92 10 84 9 76 8 68 7 60 6 52 5 44 4 36 3 28 2 20 1 12 Number of biosecurity steps taken 0 100 1 86 2 71 3 57 4 43 5 29 6 15 7 0 Use of a boat for angling Yes 100 No 0 Trailer movement of boat between venues Every trip 100 Most trips 67 Rarely 33 Never 0

Preliminary risk results

Signage

• Control can be highly successful

• Needs to be carefully considered

• Prevention is better than cure

• Lower cost association

• No impacts on associated species

• Targeted direction of scant resources

• National Angling Development Plan

• Public submission phase

Conclusion

• Core Funding

• IT Sligo presidents bursary

• IFI

• Support from IFI

Acknowledgements

Davis, Mark A., Matthew K. Chew, Richard J. Hobbs, Ariel E. Lugo, John J. Ewel, Geerat J. Vermeij, James H. Brown et al. "Don't judge species on their origins." Nature 474, no. 7350 (2011): 153-154.

Lucy, F. E., & Panov, V. E. (2014). Keep beating the drum: ICAIS confirms aquatic invasive species are of continuing concern. Aquatic Invasions, 9(3), 239-242.

Olden, J. D. (2006). Biotic homogenization: a new research agenda for conservation biogeography. Journal of Biogeography, 33(12), 2027-2039.

Ricciardi, A. (2007). Are modern biological invasions an unprecedented form of global change?. Conservation Biology, 21(2), 329-336.

Roman, J., & Darling, J. A. (2007). Paradox lost: genetic diversity and the success of aquatic invasions. Trends in Ecology &Evolution, 22(9), 454-464.

Sheehan, R., Caffrey, J. M., Millane, M., McLoone, P., Moran, H., & Lucy, F. (2014). An investigation into the effectiveness of mechanical dredging to remove Corbicula fluminea (Müller, 1774) from test plots in an Irish river system. Management of Biological Invasions, 5(4), 407-418

Simberloff, Daniel, Jean-Louis Martin, Piero Genovesi, Virginie Maris, David A. Wardle, James Aronson, Franck Courchampet al. "Impacts of biological invasions: what's what and the way forward." Trends in Ecology & Evolution 28, no. 1 (2013): 58-66.

Wittmann, M. E., Chandra, S., Reuter, J. E., Caires, A., Schladow, S. G., & Denton, M. (2012). Harvesting an invasive bivalve in a large natural lake: species recovery and impacts on native benthic macroinvertebrate community structure in Lake Tahoe, USA. Aquatic Conservation: Marine and Freshwater Ecosystems, 22(5), 588-597.

Reference