TRAPPING RESULTS FOR NASHVILLE NEIGHBORHOODS UNCOVERS LOW MOSQUITO KILLS, QUICK RECOVERIES AND VIOLATIONS OF POLICY

The Health Department made claims they sprayed because of the large numbers of mosquitoes in some Nashville neighborhoods. However, under the Tennessee Open Records Law, the No Spray Coalition requested results for all the neighborhoods that have been sprayed this year and found that this was not always the case.

Below are the trapping results we were given by the Health Deparment. In one case, the mosquitoes were reduced only by 10% after spraying and in other neighborhoods mosquitoes recovered quickly and surpassed the prespray levels (by almost 300% in Donelson). This may mean that mosquitoes are developing resistance to the spray.

The results also uncovered four violations of their mosquito spraying policy that requires a minimum of 35 mosquitoes in a trap 48 hours before they spray. Violating this policy can also make mosquito problems worse by creating resistant mosquitoes.

VIOLATIONS OF POLICY:

SYLVAN PARK, Normandy Circle (click here)

DONELSON, Quail Run (click here)

HWY 70/100 WEST MEADE, Cana Drive (click here)

NORTH NASHVILLE, Hamilton Road site 37218 and location of one positive mosquito pool test found on 6/02/06

Date # mosquitoes
5/02 ... 122
5/04 ... 172
5/09 ... 159
5/11 ... 97
5/15 ... 65
5/18 ... 174
5/23 ... 174
5/25 ... 217
6/02 ... 244
6/06 ... 98
6/08 ... 236
6/13 ... 105 (one positive mosquito test was returned sometime around this date)
6/15 ... 100 SPRAYED
6/20 ... 90 (10% reduction from the day they sprayed)
6/22 ... 77

East Nashville just north of Shelby Bottom, 37206

Date #Culex mosquitoes
5/02... 655
5/04... 935
5/09 ... 785
5/11 ... 394
5/16 ... 144
5/18... 1094
5/23 ... 821
5/25 ... 858
5/31 ... 508
6/02... 247 (what happened?)
6/08 ... 1372
6/13 ... 316 (what happened-what did they do?)
6/14 ...SPRAYED
6/15 ... 132
6/20 ... 336 (numbers go above prespray number)
6/22 ... 66 (Test site numbers were down across Nashville during this weeks this whether they were sprayed or not.

ANTIOCH permanent trap location, 37013

Date #Culex mosquitoes
5/02 ... 87
5/04 ... 54
5/11 ... 144
5/16... 47
5/18 ... 232
5/23 ... 557
5/25 ... 94 (What did they do?)
6/02 ... 305
6/06 ... 4 (What did they do? This may be an error in their test.)
6/8 ... 65
6/13 ... 100
6/15...74 (They made the decision to spray this area on this date but was canceled due to equipment problems.)
6/20 ... 64
6/22 ... 3 (The decision to spray on 6/26 was made on this date but it was canceled.)

We spoke to a woman in this neighborhood who has a drainage problem from poor construction by our city. She claimed that after they larvicided, the problem was significantly better. She wants to know why the city is allowing poor engineering that creates drainage problems in the first place.

1 mile north west of the location in Antioch (listed above) they trapped on 6/15 found 450 mosquitoes. This may be why they elected to spray but the low number in the permanent trap site on this same date shows how different mosquito populations can be. Certainly, there must have been a place where mosquitoes were breeding in this area. If the Health Department would hire enough seasonal helpers perhaps they could have done something about this but Mother Nature took care of the problem 2 weeks later without spraying.

The MPHD's Mosquito Control Policy states:

"The primary action threshold for ULV truck-mounted application of Anvil is the identification of a pool of mosquito positive for WNV or the identification of a human case.

However, the minimum action threshold for initiating ULV truck-mounted application of insecticide is a mosquito population density of 35 female mosquitoes in a gravid trap....

In making the decision for ULV truck-mounted application of insecticides based on minimum action threshold, mosquito density data used in make such decision must be from the area of concern and must have been collected within a period not exceeding 48 hours prior to initiation of treatment. "
Source: http://healthweb.nashville.gov

Locations and dates of positive mosquito pools as of July 17, 2006:
6/02/06 Hamilton Road 37218 (North Nashville) no other positive test have occurred.
6/13/06 William Bailey Drive 37207 (North Nashville) 2 positive tests were found. No other positive tests have occurred.
7/18/06 Shadow Lane, 37206 (East Nashville) no other positive test have occurred.
7/18/06 Quail Run Court, 37214 (Donelson) no other positive test have occurred.