Week 27 – June 29-July 5

2014 MOSQUITO REPORT: WEEK 27

Report based on data collected from traps deployed the week of June 29- July 5, 2014. Report prepared by Chan Suom, Dave Lawson, and Nate Boonisar.

1. CURRENT MOSQUITO ACTIVITY/TREND

CDC Light Traps:
CDC light trap activity has increased as about half the towns in the county have reported higher than average numbers of host-seeking mosquitoes whereas the other half of the county recorded lower than average levels of activity. Only Norwood’s collection size remained consistent with the historical average.

Gravid Traps:
Gravid trap activity is primarily lower than average when compared with hoistorical data. Only Braintree collected a higher than average number of ovipositing mosquitoes. Some of our eastern trap sites, normally average to higher than average in collections, may have been exposed to ULV spraying. These particular traps were set out on a Thursday night which conicided with our scheduled ULV spraying for that part of the county.

 2. CURRENT PREDOMINANT SPECIES

CDC Light Traps:
The most abundant mosquito species this week are Coquillettidia perturbans of which over 13,300 were collected from across the county. This was followed by Aedes vexans(1,600+) and a declining Ochlerotatus canadensis (200+) population.

Gravid Traps:
Culex pipiens/restuans are the main species in these traps and their overall population is lower than average for this time of the season.

3. COMPARISON TO PREVIOUS SEASON

The overall mosquito population for host-seeking mosquitoes in CDC light traps is mixed whereas gravid trap activity is lower than average when compared to historical data (2007-2013). Coquillettidia perturbans has emerged in high numbers as we have collected over 13,000 specimens from around the county. Aedes vexans appears to be most active in parts of Bellingham, Dover, and Medfield which indicates localized flooding due to one circumstance of another despite the recent lack of rain. Ochlerotatus canadensis populations are on the decline for the most part. We are seeing more ofAnopheles punctipennis but they are localized to parts of Dover, Medfield, and Walpole.

Please refer to our surveillance charts for detailed trap collection data.

4. WEATHER SUMMARY

Temperatures this week were generally above normal with higher humidity. Hurricane Arthur passed 150 miles southeast of the district but brought heavy rains to the area. Rainfall ranged from 1.5 to 3 inches from west to east across the district. While a general rainfall occurred, amounts were locally variable due to the convective nature of the precipitation. Some specific amounts:

Franklin: 2.06”
Norwood (District Headquarters): 1.62”
Norwood Airport: 2.48”
Sharon: 2.40”
Stoughton: 2.20”
Quincy: 2.75”

Despite the rainfall, 30,60, and 90 day deficits remain between 50-90% of normal, with drier conditions to the west.

Total weekly rainfall: 1.62 inches (+0.91 in.)
Total Monthly rainfall: 1.62 inches (+1.11 in.)
Total Yearly rainfall: 21.03 inches (-0.75 in.)

5. NUMBER OF REQUESTS FOR SERVICE

We had 497 calls for service this week which is a total of 4,340 service requests for the year.

6. MCP/COMMISSION RESPONSE

The District is currently responding to requests for ULV applications with our evening ULV application program. Catch basins are being treated in the District’s towns. Requests from residents for ground larvicide applications are continuing, but the majority of these requests are now revealing sites that are drying up, or are devoid of mosquito larvae.

Contact

144 Production Rd, Suite C

Walpole, MA 02081

Office: (781) 762-3681
Fax: (781) 769-6436