NORTHWEST MOSQUITO ABATEMENT DISTRICT

147 W. Hintz Rd.

Wheeling, IL. 60090

Phone: (847) 537-2306

Fax: (847) 537-2583

www.nwmadil.com

 

                                                                                                 Mosquito Update

                                                                                                        June 16, 2008

 

PRESENT CONTROL STATUS:

 

NUISANCE MOSQUITOES

Nuisance floodwater mosquito broods (Aedes vexans) continue to increase as rainfall events continue.  Biting mosquito problems will increase as normal warm temperatures arrive.

 

New Jersey Light Trap counts are not excessive yet but increasing now that the warm weather has arrived. Some heavily forested areas have more noticeable numbers.

 

Crews have been larviciding since the latter half of April, treating infested water areas for the developing mosquito larvae with methoprene, MMFG & Bti.  Continued re-flooding of floodwater areas continue to exasperate the situation creating new mosquito production areas.

 

CULEX MOSQUITOES

Culex mosquitoes are increasing as indicated by gravid traps.  Residents of the District are advised to inspect their properties for stagnant water filled containers that may produce these types of mosquitoes.  Examples of mosquito production areas encountered by homeowners can be viewed at: http://www.nwmadil.com/breeding sites1.htm. 

 

Crews are currently treating stagnant ground surface water sources with methoprene pellets, MMFG, Bti & Bacillus sphericus. Catch basin treatments have been started.  Culex pipiens larvae have been prevalent in ditches culverts and other stagnant water areas after rainfalls and these are being treated at the same time as the nuisance mosquitoes.

 

DIRECTOR’S NOTE:  Once again I wish to thank those cities/villages and municipalities that provided maps of off-road & backyard catch basins, subterranean vaults, pumping stations, flood control structures, tire pile locations, new building constructions and building foreclosures!  Your assistance will help our control efforts to further minimize the effects of West Nile Virus.

 

MOSQUITO VIRUS SURVEILLANCE IN ILLINOIS

Mosquito batches testing positive for these viruses will be posted at the following website address:

http://www.nwmadil.com/VECTEST2008.htm. 

 

The Illinois Department of Public Health has reported that three batches of mosquitoes tested positive for West Nile virus (WNV) from the Cook (City of Evanston), Dupage & Tazwell counties thus far in 2008. More information about WNV can be found on the state’s website www.idph.state.il.us/envhealth/wnv.htm or by calling 217-782-5830.  The State’s website also has other valuable resource links on WNV, pesticides and mosquito control.

 

 

NWMAD WEBSITE:

Report 10-day standing water problem: http://www.nwmadil.com/water source rpt.htm

Report sick/dead birds or other animals: http://www.nwmadil.com/Dead Birds.html

Check night time mosquito spraying schedules:  http://www.nwmadil.com/nitespry_map.html

 

RAIN BARRELS, a mosquito perspective:

Conserving energy and resources is certainly the current rage given the rising costs of fuel, ever increasing water demands, housing crisis and the very popular threat of global warming. People are looking for intelligent alternatives to conserve resources and give back to the Earth what is taken for the sake of human existence.

 

Rain barrels easily fit the conservation momentum of today.  An age-old idea reconstituted into modern plastics and marketed to a resource worried society. What exactly are rain barrels and how do they work?  In simplest terms they are cisterns or containers designed to hold storm water run-off for later return (or re-charge) of a soil or water source.  Typically, they are used to collect rainfall from roofs via house gutter systems for supplemental watering of soil and plants. Do they work?  Yes!  However, from a mosquito perspective we need to exercise some caution and common sense when deciding to use them.

 

Cisterns or rain barrels may also contribute to mosquito problems if they are not regularly inspected, maintained and constructed or installed to be mosquito-proof!  Cisterns were documented and/or likely mosquito production sources during major yellow fever outbreaks in Philadelphia, New York, Boston, Baltimore, Norfolk, Memphis and New Orleans (1700-1900’s). Although water and sanitation systems have greatly improved since the 1700-1900’s and the yellow fever mosquito is not a problem in Illinois, it would still not be advisable to create widespread cistern-like habitats for other medically important mosquitoes found in Illinois (i.e. Culex pipiens, Aedes albopictus, Ochlerotatus japonicus, Oc. triseriatus and other species)!   

 

How might rain barrels contribute to the production of mosquitoes?

 

  1. Rain barrel screening designed to exclude mosquitoes will pass organic debris normally present in rain gutters especially common during the spring flower & seed drop and autumn leaf drop.  If rain barrel water is not used frequently it may stagnate and produce mosquitoes if they gain entry into the barrel.  
  2. Maintenance issues!  If screens or attached downspouts to the rain barrels are damaged or not tightly fitting they may not exclude mosquitoes. Gutter diverters with silt traps if used with rain barrels may create additional mosquito habitats (i.e. similar to catch basin problem and Culex mosquitoes).
  3. Potential freeze damage of rain barrels if not removed or drained before freezing temperatures occur may jeopardize mosquito-proof qualities.  
  4. Given the current stalled housing-loan market we are also seeing more foreclosed houses vacant and in disrepair for longer periods of time.  This means more stagnant containers, neglected swimming pools and possibly-unmaintained rain barrels that may produce a mosquito problem. 

 

 

REDUCING THE RISK OF MOSQUITO BITES:

Avoid outdoor activity if possible from dusk to dawn when the mosquitoes bite the most.  If you do go out wear light colored, loose fitting, protective clothing and insect repellent (always read label warnings and directions).  Make sure mosquitoes do not enter homes through unscreened or broken doors or windows.   Residents are encouraged not to create mosquito harborage areas.  Make sure tall grassy areas are trimmed and other unnecessary vegetation is cut back.  If plants must be watered do so in the morning so the vegetation and soil has a chance to dry making it less attractive to mosquitoes.  Empty any containers holding stagnating water for 5 days or longer like: tire casings, birdbaths, flowerpots and barrels that may produce mosquitoes. Make sure rain barrels or other storm water runoff cisterns are fitted properly when installed, well screened, free of detritus or organic material and mosquito-proof.  Neglected swimming pools may produce thousands of mosquitoes.  Call the District to report large stagnant water areas that remain wet for more than 7 days.

 

Mike Szyska

Director

PLEASE FORWARD THIS INFORMATION TO APPROPRIATE DEPARTMENTS AND AGENCIES.