Week 33 – Aug 12-18

2012 MOSQUITO REPORT: WEEK 33

Report based on data collected from traps deployed the week of August 12-18, 2012. Report prepared by Chan Suom, M.S., Dave Lawson, and Nate Boonisar.

1. CURRENT MOSQUITO ACTIVITY/TREND

CDC Light Traps:
Host-seeking trap collections are indicating a return to average numbers of mosquitoes when compared with the historical average. Only Foxborough collected higher than average numbers of mosquitoes whereas Avon, Braintree, Canton, Dedham, Franklin, Holbrook, Medfield, and Medway reported lower than average abundances.

Gravid Traps:
Gravid traps continue to report lower than average numbers of ovipositing mosquitoes throughout most of the county. Only Bellingham, Foxborough, and Medway collected higher than average numbers of mosquitoes.

 2. CURRENT PREDOMINANT SPECIES

CDC Light Traps:
The most predominant CDC trapped mosquitoes in Norfolk County this week were Coquillettidia perturbans, with populations higher than average in Foxborough once again. There appears to be a development of Psorophora ferox  species that are appearing throughout the district and this is likely the result of previous rain events. There are also many Uranotaenia sapphirina, an insignificant species, which usually appears at this time towards the latter half of the season.

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

Coquillettidia perturbans populations are higher than average only in Foxorough, otherwise mosquito populations are relatively similar to previous years’ data. Except in Foxborough, Aedes vexans populations are average to below average, despite previous rain events. Culex pipiens/restuans numbers are about average throughout the district. Culiseta melanurapopulations remain depressed.

4. WEATHER SUMMARY

Temperatures were slightly above normal this week, but a strong cold front brought significantly lower temperatures by Saturday. A system on Wednesday brought localized heavy rainfall to much of the area. Amounts were generally over ½ inch with amounts over 1 inch in a small swath along the I-95 corridor. Another system on Saturday brought light rainfall, generally under ¼ district-wide. So far this month, rainfall has ranged from as low as 1 inch in the far southwest, to over as 4 inches in the far east. Most of the district has had above normal precipitation this month, and 60-90 day rainfall has been below normal in the west to slightly above normal in the east.

Total weekly rainfall: 0.67 inches (-0.09 in.)
Total Monthly rainfall: 2.52 inches (+0.61 in.)
Total Yearly rainfall: 20.31 inches (-5.94 in.)

5. NUMBER OF REQUESTS FOR SERVICE

NCMCD has received 7,320 calls year to date for services as of 8/17/12. The NCMCD received 671 calls for service this week.

6. MCP/COMMISSION RESPONSE

The NCMCD continues to respond to ULV requests by residents. With the recent finding of multiple EEE positive pools of Cq. perturbans in Canton, the District has stepped up additional ULV applications in Canton and Randolph. Basin treatments have been completed in most communities in our district and we are scaling down this operation as the season draws closer to autumn. Very few larvicide requests are being initiated at this time.

Contact

144 Production Rd, Suite C

Walpole, MA 02081

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