Week 31 – July 27-Aug 2

2014 MOSQUITO REPORT: WEEK 31

Report based on data collected from traps deployed the week of July 27- August 2, 2014. Report prepared by Chan Suom, Dave Lawson, and Nate Boonisar.

1. CURRENT MOSQUITO ACTIVITY/TREND

CDC Light Traps:
CDC light trap collections were lower than the historical average for most towns in our county. Only Dedham, Dover, Randolph, and Weymouth collected a higher than average number of host-seeking mosquitoes. Medfield, Norwood, Stoughton, and Westwood reportyed average levels of mosquito biting activity.

Gravid Traps:
Gravid trap activity remains lower than the historical average; only Norfolk collected a higher than average number of ovipositing mosquitoes.

 2. CURRENT PREDOMINANT SPECIES

CDC Light Traps:
The most abundant mosquito species this week are Coquillettidia perturbans of which over 1,600 were collected from across the county. This was followed by Aedes vexans,of  which over 200 specimens were collected.

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 lower than average when compared with the historical average (2007-2013). Coquillettidia perturbans populations are higher than average for the most part, but their peak has passed and their numbers have declined to a third of last week’s figures (from 4,600+ to 1,600+). Aedes vexans populations have also dropped to a quarter of last week’s figures (from 800+ to 200+ specimens).

Gravid trap collections have been lower than average thus far this season. A change in our mosquito attractant brew may remedy this and return collections that better reflect the historical data and current activity of ovipositing mosquitoes.

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

4. WEATHER SUMMARY

Temperatures this week averaged below normal. Showers and thunderstorms in the early part of the week affected areas mainly along and west of I-95 where widespread 0.75” to 1.5” fell. East of I-95, far less rain fell during the week with amounts generally close to 0.25.” Some of that fell on Saturday across these areas but amounts were under 0.25”. For the month of July, rainfall was above normal across much of the district, especially along the northern areas. Rain was below normal across the immediate western and southern border towns where most of the month’s rain fell during hurricane Arthur at the beginning of the month.

Total weekly rainfall: 1.22 inches (+0.51in.)
Total Monthly rainfall: 3.94 inches (+0.88 in.)
Total Yearly rainfall: 23.71 inches (-0.83 in.)

5. NUMBER OF REQUESTS FOR SERVICE

We received 429 calls for service this week. We have recorded a total of 6,457 service requests for the year.

6. MCP/COMMISSION RESPONSE

The District is currently responding to requests for spraying with our evening ULV application program. Catch basins continue to be treated in a few of the District’s towns with a majority of the towns’ treatments having been completed at this point. A small number of larvicide requests from residents continue to be checked as needed. The District is currently conducting some ‘low-flow’ water management projects.

Contact

144 Production Rd, Suite C

Walpole, MA 02081

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