Week 35 – Aug 26-Sept 1

2012 MOSQUITO REPORT: WEEK 35

Report based on data collected from traps deployed the week of August 26- September 1, 2012. Report prepared by Chan Suom, M.S., Dave Lawson, and Nate Boonisar.

1. CURRENT MOSQUITO ACTIVITY/TREND

CDC Light Traps:
Host-seeking traps continue to report average numbers of mosquitoes from most of Norfolk County. Along with Foxborough showing higher numbers, Weymouth continues to experience above average mosquito activity. Canton, Franklin, Holbrook, Medway, Needham, and Plainville report a decline in host-seeking mosquito activity.

Gravid Traps:
Gravid traps continue to indicate lower than average numbers of ovipositing mosquitoes. Only Franklin is collecting higher than average numbers in its gravid trap.

 2. CURRENT PREDOMINANT SPECIES

CDC Light Traps:
The most predominant CDC trapped mosquitoes in Norfolk County this week were Aedes vexans, with populations higher than average in Foxborough and Quincy. There are some noticeable populations of Psorophora ferox where there are Ae. vexansemergences. Oddly enough, there appears to be a slight re-emergence (?) of more Oc. canadensis which can be observed in Holbrook and Sharon.

Gravid Traps:
Though their populations are low, Culex pipiens/restuans are the most predominant species in gravid traps throughout Norfolk County.

3. COMPARISON TO PREVIOUS SEASON

The overall mosquito population is average throughout Norfolk County. The northeastern part of our county received more precipiation in the last rain event that faciliated the development of flood and salt marsh species that we are now experiencing in Quincy and Weymouth: Ae. vexans, Ae. taeniorhynchus, Ae. sollicitans, and Ps. ferox. The weather was cooler during our trapping interval and this may have been a factor in our low turnout in gravid traps.

4. WEATHER SUMMARY

Temperatures this week were generally above normal, but with overall lower humidity making for cooler nights. A cold front on Tuesday brought torrential rain to the district. Heaviest rains fell along a west to east swath across the middle of the district were amounts of 1-2 inches fell in under an hour (heaviest far west and east). Lesser amounts of under ½ inch fell across the extreme north and south of the district.

Total August rainfall was varied across the district ranging from as low as 2 inches in the far southwest to as much as 5-6 inches in localized areas in the east. Overall, there was below normal precipitation closer to the Rhode Island border and across Dover/Westwood/Needham, slightly either side of normal across central regions, and above normal across the east (mainly along the southern border towns from Stoughton east to South Weymouth).

Total weekly rainfall:  1.34 inches (+0.55 in.)
Total Monthly rainfall: 3.86 inches (+0.49 in.)
Total Yearly rainfall: 21.65 inches (-6.17 in.)

5. NUMBER OF REQUESTS FOR SERVICE

NCMCD has received 8,654 calls year to date for services as of 8/31/12. The NCMCD received 648 calls for service this week.

6. MCP/COMMISSION RESPONSE

The NCMCD continues to respond to ULV requests by residents. We have also responded to many towns requests to spray on school properties before and at the beginning of the school year, both in towns with documented virus activity and towns with no documented activity. And we continue to treat localized neighborhoods surrounding locations of trap sites with positive EEE and WNV pools. Basins treatments have been suspended, and ground larviciding continues at a low pace.

Contact

144 Production Rd, Suite C

Walpole, MA 02081

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