Week 37 – Sept 11-17

2011 MOSQUITO REPORT: WEEK 37

Report based on data collected from traps deployed the week of September 11, 2011 through September 17, 2011. Report prepared by John Smith, Chan Suom, M.S., and Nate Boonisar.

1. CURRENT MOSQUITO ACTIVITY/TREND

CDC Light Traps:
Host-seeking activity generally reflected the aftermath of tropical storms and recent rain events with trap sites near flood plains reported higher than average activity. Towns that had higher than average activity include Avon, Canton, Medfield, Medway, Millis, Needham, Norfolk, parts of Sharon, parts of Walpole, and parts of Weymouth. Only Quincy experienced lower than average biting levels and the remaining towns in our service area reported average levels of biting activity.

Gravid Traps:
Gravid trap collections are mixed again this week. Most towns had average levels of activity. Bellingham, Dover, Medway, Norwood, parts of Sharon, andWeymouth had higher than average gravid mosquito activity whereas Dedham, Franklin, Millis, and Milton reported the opposite trend.

2. CURRENT PREDOMINANT SPECIES

CDC Light Traps:
Aedes vexans continues to be the most active mosquito species in our county as a result of the previous rain events; and their activity levels are high in Canton (1,100+ in one trap!), Medfield, Millis, Needham, Sharon, Walpole, and Wrentham. Psorophora ferox is incredibly active in Canton (1,400+), Medfield, Millis,Needham, Norfolk, and Walpole. Ochlerotatus trivittatus has also made a big appearance in Canton, Millis, Needham, and Walpole. Culex pipiens/restuanshost-seeking activity is high in Canton, Medfield, Medway, Millis, and Walpole. Culiseta melanura has become quite abundant in Avon, Medway, Millis,Sharon, Walpole, and Weymouth. Ochlerotatus canadensis numbers continue to be higher than average in Sharon.

Gravid Traps:
Gravid Culex pipiens/restuans mosquito populations are mostly average this week. Avon collected an unusually higher than average number of Oc. japonicusmosquitoes in its gravid trap.

3. COMPARISON TO PREVIOUS SEASON

The continued weekly rain events have created and maintained plenty of habitat for flood-type and mammalophilic mosquitoes as seen from this week’s Ae.vexans, Ps. ferox, Oc. trivittatus, and Oc. canadensis populations. Culiseta melanura numbers are larger than usual and their widespread occurrence in many towns suggests that they are also benefitting from the recent spate of wet weather. As our trapping season draws to a close in a couple of weeks, we are seeing fewer non-flood species which is indicative of the forthcoming colder season. Virus activity is still something to be cautious about until the first hard frost arrives, which should kill off most mosquitoes.

4. WEATHER SUMMARY

No weather report available this week.

5. NUMBER OF REQUESTS FOR SERVICE

NCMCP received 7,598 calls year to date for service as of 9/16/11. NCMCP received 283 calls for service this week.

6. MCP/COMMISSION RESPONSE

NCMCP discontinued all ground ULV applications and rain basin treatments effective Thursday, September 15, 2011. Adult mosquito surveillance (Gravid Traps and Light Traps) will continue through the end of the month. NCMCP personnel have shifted operations to water management activities. There will be plenty of debris clearing necessary in mosquito control drainage systems across the county compliments of Tropical Storm Irene.

Contact

144 Production Rd, Suite C

Walpole, MA 02081

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