Hardys Bay Residents Group

Minutes

SPECIAL MEETING – mosquitoes

Minutes of the meeting held at 7.30 pm Monday 18 September, 2006, Killcare Surf Club.

President, Adrian Williams welcomed all and extended sincere thanks to guest speakers Mike Muller and Professor Cameron Webb.  Mike is the Medical Entomologist with Brisbane City Council’s Vegetation and Pest Services, and Cameron is from the Department of Medical Entomology at Westmead Hospital, who manage a salt marsh mosquito program for Sydney Olympic Park in Homebush.

Adrian Williams - Overview:

• The first mosquito control meeting was in February this year.  There have been a number of meetings with Gosford City Council and consultation with Mike Muller and Professor Cameron Webb over this period.
• Council meeting Tuesday week ago, report to Council asking them to seek advice from other areas to treat and control mosquitoes.  Brisbane, Gold Coast & Port Stephens Councils have been successful in controlling salt marsh mosquitoes.
• Still issues with National Parks and Wildlife.  Not for or against – not time to do all BTI testing. Want to obtain further data.
• Lower Hunter Regional Co-ordination Management Group is working on mosquito control.
• Keeping the issue alive.  Jim Macfadyen and Trevor Drake’s motion to invite Mike Muller to talk to Gosford City Council on Tuesday 19^th. National Parks & Wildlife will also be there.  Experts to talk and see what can be done.
• Treatment in November – optimistic – HBRG still pushing.
• Met with Bob Debus, Minister for the Environment, last Tuesday in regard to restoration of the bay – the oyster lease clean up and the mosquito issue.

Mike Muller:

• Conveyed thanks to Gosford City Council for bringing him down and the opportunity to speak to HBRG and acknowledged Professor Cameron Webb.  Sandy Robinson was his first point of contact some four years ago – what’s being done in Brisbane with salt marsh mosquitoes.
• Mike is not here as an advocate – just to give the facts.
• Brisbane Council’s mosquito management (not control) program.  Liveable lifestyle. 
• Public health issue – Ross River and Barmah Forest Virus as well as pets with heartworm.  43 different species in Aust. Not all transmit Ross River.  Spraying BTI will reduce but won’t totally eradicate.
• Management based on Larviciding.  Aim is to get through the run in time to prevent mosquito larvae getting to adult stage.  Only on public land.
• Big target is tidal wetlands owned by Council.  They breed tens of millions and travel ten kilometres.
• From mid 90’s using BTI (bacillus thuringiensis israelinis).

BTI is a natural occurring soil bacteria.  The protein produced crystallises and the           larvae have to eat it.

• The key chemical supply is the right amount, right product, and right place at the right time.  Time is critical – tides, temporary pools.  Very sensitive to tide variation and rain.  24-48 hours after post treatment observation.
• Egg to adult in 7 days.  A very narrow window.  The first 3-4 days susceptible to BTI.
• Education to take responsibility in our own backyards – bromeliads harbour mosquitoes – leaving water bowls around the house and water tanks.
• Mosquito & Arbovirus Research Committee, Qld Inst. Medical Research has had enquiries from Gosford Council.  BTI 38,000 times less toxic before killing shrimp.
• 8 year study Minnesota Wetlands in America has shown no long term negative impact on non-target insects, birds or frogs. 

Professor Cameron Webb & Mike Muller: In response to Q & A –

• Homebush Bay monitoring showed 6,000-10,000 per trap.  After spraying BTI an 85-90% reduction to 1,500 per trap.  Still after heavy rain and very high tides there were some mosquitoes.  Balance of lifestyle and environment. Control program sets a base line.  Expect to get 100% of targeted areas allowing small % for wind change. Overall very positive results.
• Brisbane Council unable to do Empire Bay spraying.  Could assist and Cameron’s group could help Gosford council.  Computer monitoring – similar to National Parks weed control adopted by contractors.
• Generally salt marsh all hatch around the same time within 12-24 hrs.  The number of treatments vary depending on location.  Homebush Nov-Apr one per month.  Over 60ml rain in 3 days they have to do control.
• Correlation between mangroves and mosquitoes breeding – very little.  Bulk salt marsh is next layer up above mangroves.  Temporary pools are more problems for breeding.  Breed in these pools then move on. 
• Cameron is involved with five Councils, National Parks, Fisheries and Conservation groups in the Lower Hunter Regional Co-ordination Management Group.  Early days – more about community education.
• 20 species in our area identified.  Of the 4 salt marsh, 1 to be targeted.
• Ross River Virus and Barmah Forest widespread in Aust. Can’t predict outbreaks. Fresh water pools in homes – struggling to control.
• The key driver of salt marsh problems are the temporary pools. 8-9 days to complete cycle and emerge.
• Habitat modifications to eradicate temporary pools unacceptable by EPA as salt marshes are being lost at a rapid rate.
• Only salt water control is undertaken at Homebush, not fresh water.  Funded by Sydney Olympic Park funds -wetlands and sporting venues.

Adrian Williams:

• Scientifically based proposal using BTI in the management of salt marsh mosquitoes.
• Misinformation going around.  Department of Health shows results for Killcare area.
• Other local residents groups support us – visitors come and they don’t come back.
• Cameron’s report to Gosford Council was a costing for the pilot scheme $40,000,

$10,000 - $12,000 monitoring and $6,000 per treatment of BTI.  4-6 treatments.  Council officers have advised there is nothing in Council’s budget.  HBRG have $6,000 pledged by public and a grant application for $7,500.

• Gosford Council have a duty of care with Ross River Virus. Bill Teasdale hospitalised.
• Councillor’s aware HBRG has credibility and want to show how to fix it and with funding we try to help out. Trevor Drake, Jim Macfadyen and Grant McBride’s office have been fantastic.  9 to 1 vote from Council for Mike to come down from Brisbane.
• Aware of grant for bat boxes – no studies out – no impact on the numbers.  Not a mosquito control option – adjunct to integrated control program.
• HBRG to continue to work with authorities for mosquito management.
• Thanks conveyed to Mike and Cameron.

Meeting closed 9.20 pm.