This presentation was given to an ad hoc Beaver Committee for the Town of Charlton in 2004.


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This slide outlined the topics for this presentation.

Title page

A listing of the 9 mosquito control districts in Massachusetts. Towns join by vote at an Annual or Special Town Meeting.

A color-coded map showing the locations of the 9 mosquito districts. This map is also on our website at White areas do not have a program at this time.

A more detailed map showing the CMMCP service area (in yellow). The website also has this map at: white towns do not have a program; gray towns are in other mosquito control districts.

The 5 components of a full mosquito control program. Additional information on these services offered by CMMCP is available at

Surveillance traps used at CMMCP in 2004. Gravid means egg-bearing, and these traps are designed to attract pregnant female mosquitoes. These specimens are important because they have already taken at least 1 bloodmeal and potentially have been exposed to virus. Gravid traps are a great device for Culex and certain Ochlerotatus species. These traps use hay infusion (stagnant) water as an attractant.


CDC light traps use either light, CO2 or a combination to attract female mosquitoes. CDC light traps can attract a greater number of mosquito species, but not always ones that have been exposed to virus.



For more information try this link:


Types of mosquito-borne viruses (call arboviruses) our surveillance focuses on at this time. All samples are sent in weekly to the Mass. dept. of Public Health State Lab. In Jamaica Plain. Results are sent to CMMCP within a few days. If a collection (called a pool) is identified with virus, intervention strategies are considered depending on many factors, such as species identified, virus identified, time of year, current population levels, etc.

The Public Education page, with our PR brochure in yellow. Each year we give talks to schoolchildren, mostly K-8. Presentations are tailored to meet the needs of each audience. For the K-8 classes we have handouts (coloring books) that teach about basic mosquito biology and control techniques for homeowners. We also leave a container with mosquito larvae that the children watch the transformation into adults.

2 types of wetlands restoration, hand and mechanized. Restoration of degraded ditch systems is an integral part of our program, reducing and sometimes eliminating mosquito breeding in an area, without the need for continued larval surveillance and pesticide applications. Determinations are made at each site to decide whether hand or machine work is needed, or no work at all.



For more information check here:

The Larval Control title page. The Technician in the picture to the left is sampling the swamp, a procedure called dipping. If he identifies sufficient numbers of mosquito larvae, a bacterial product called Bti is applied. This bacterium is specific to mosquitoes, and has little to no negative impact on other aquatic organisms. For more information on Bti check here:


The photo on the right side is a close-up of 3 mosquito larvae. Each larva goes though 4 stages, called “instars” until it becomes a pupa, the final aquatic stage before emergence as an adult. Here is more information on mosquito larvae:

 & mosquito pupae:


The different control products in use at CMMCP for larvae & pupae – more information is here:


To the left, a truck utilizing an ULV spray rig – ULV stands for Ultra Low Volume, a technique used to dispense fine, dilute droplets of product to minimize negative effects on non-target organisms. Information on this part of the program can be found at


The picture to the right is an adult mosquito, a sight many of us are familiar with.

Information on the product used for adulticiding, also called spraying. More information is here:

The Mosquito-borne Diseases title page

A brief introduction on West Nile Virus – a search on Google or any search engine for WNV will result in many websites devoted to this topic.

A graphic from the CDC website here showing locations of WNV in 2003.

WNV information from the CMMCP service area in 2003.

An explanation for the WNV virus cycle.

An introduction to Eastern Equine Encephalitis, or EEE. This arbovirus is making resurgence in Massachusetts and merits special attention and concern.

An explanation of the EEE cycle, similar to WNV.

The Mosquito Biology title page

The 4 stages of the mosquito’s life cycle. Information on the mosquito life cycle can be found at


The graphic shows a female Culex mosquitoes laying eggs, forming an egg raft on top of the water. The possible locations of eggs described here vary by species and can be very specific for each type of mosquito. Check here for more information on mosquito eggs:


A narrative on mosquito larvae – note the close up picture to the right. Most larvae will darken in a few hours after hatching from the egg. This link has information on mosquito larvae:


A narrative on the mosquito pupae. This stage is comparable to the cocoon stage of the butterfly. Mosquito pupae are very active and are easily disturbed and can be difficult to survey. Mosquito pupae information can be found here:



A narrative on the mosquito adult – the graphic shows a mosquito emerging from the pupal case. Once emerged, it will need to rest for a time to dry its wings. It will usually then mate and seek a food source, often plant nectar. The blood the female seeks is for egg production, the male mosquito does not seek bloodmeals. Information on this stage of the mosquito life cycle is here:


Title page

The discussion turned towards beaver impacts on mosquito production. A presentation was made at the Dec. ’02 NMCA meeting from a study site in New Jersey. For hard copies of this presentation please e-mail

Specifics about the NJ study.

Extensive surveillance has been performed in this area, both pre and post beaver activity.

A line graph showing the increase in total mosquito numbers.

Viral testing showing WNV from the study area.

An example of a device used to control water levels in beaver impoundments.

Results and discussion after the installation of this device in the area.

Results from the 2002 season

Results from the 2003 season.

Conclusions from this study.



Any questions on this presentation please call Tim Deschamps at (508) 393-3055 or e-mail at