mosquitoes, wetlands and aquatic plants
DESCRIPTION
Managing mosquitoes associated with constructed and rehabilitated wetlands is a major concern. A key factoring influencing mosquito production is aquatic vegetation. Here are the key slides from a presentation from ‘Managing constructed wetlands and water plants’ workshop at Sydney Olympic Park, NSW, Australia.TRANSCRIPT
Mosquitoes in Constructed Wetlands
Dr Cameron Webb
Department of Medical Entomology
Pathology West – ICPMR Westmead, Westmead Hospital
Marie Bashir Institute of Infectious Diseases and Biosecurity, University of Sydney
Email: [email protected]
Twitter: @mozziebites
• Most common in Australia (~5,000 cases/pa)• Symptoms:
Not fatal but rash, fever, joint pain, polyarthritis
• Complex ecology, in different regions: Seasonal & geographic variation Different vectors
• Marsupial hosts? Bird hosts? Human hosts?
Ross River & Barmah ForestRoss River & Barmah Forest
Water Sensitive Urban Design Integration of water management into
urban planning and design Urban developments contain a suite
of water conservation strategies Constructed wetlands Bioretention swales Raingradens Rainwater tanks
Mosquito risk variable Design, construction, installation and
maintenance issues can increase the mosquito risk
Constructed WetlandsConstructed Wetlands Stormwater retention & treatment Wildlife conservation Change local mosquito diversity Change in local environmental
drivers of mosquito populations Change in reservoir hosts Wetland design & maintenance
Water quality, depth & flow rates Edge structure and slope Vegetation zones Predators
Well funded management plan
Wetlands support diverse habitats
Vegetation and mosquito risk?
Stem density: multiple stems increase refuge Growth density: more plants per area Invasiveness: create monoculture Plant litter: increase refuge & organic content Deep water tolerant: potentially greater coverage Floating plants: density & root mass provides refuge Terrestrial plants: grow into water & provide refuge? What plants are required to meet wetland objectives
Plant group Plant nameMosquito Risk
High Med Low
Emergent Alisma spp. (e.g. Water Plantain) +
Sagittaria spp. (e.g. Arrowhead) +
Cyperus spp. (e.g. Giant Sedge) +
Typha spp. (e.g. Cumbungi) +
Phragmites spp. (e.g. Common Reed) +
Bolboschoenus spp. (e.g. Clubrush) + +
Eleocharis spp (e.g. Common Spikerush) +
Persicaria spp. (e.g. Slender Knotweed) +
Floating Azolla spp. (e.g. Water Fern) +
Eichhornia spp. (e.g. Water Hyacinth) +
Lemna spp. (e.g. Duckweed) +
Potamogeton spp. (e.g. Pondweed) +
Salvinia spp. (e.g. Salvinia) +
Ranunculus spp. (e.g. Buttercups) +
Based on Knight et al. (2003) Ecol. Engineering 21:211-232 & Sainty and Jacobs (2003) Waterplants in Australia
Estimated mosquito risk associated with aquatic vegetation
Provides assistance to local governments on assessing mosquito risk associated with wetlands
Provides background on mosquito and mosquito-borne disease risk
A framework for decision making
Highlight wetland projects that may require more detailed assessments and the engagement of consultants to develop a site-specific plan
Guidelines for constructed wetlands
Wetland RehabilitationWetland Rehabilitation Accompany development More mosquitoes?
Restore tidal flooding (coastal) Environmental flows (inland)
Long-term & short-term issues Change in local environmental
drivers of mosquito populations Change in reservoir hosts Mosquito management? Are these “natural” habitats?
Regional Approaches to Mosquito RiskRegional Approaches to Mosquito Risk
Follow me on Twitter @mozziebites
Learn more about my research:
http://cameronwebb.wordpress.com
Thank you