Introduction --
Maine's Mosquitoes
What do we need to know about Maine's mosquitoes so that we can appropriately target our efforts to reduce the risks of West Nile Virus (WNV) and Eastern Equine Encephalitis (EEE)?
WNV and EEE are a diseases spread by specific types of mosquitoes under specific conditions. Entomologists indicate there are 42 - 45 species of mosquitoes in Maine. Only a few of them are actually potential vectors for WNV or EEE. A "vector" is an organism that carries pathogens from one host to another. Some mosquitoes only feed on birds, and some only on mammals. As WNV and EEE are bird diseases, the mosquitoes of concern are those that feed on both, allowing the diseases to spread from birds to mammals. It helps that the breeding locations of these vector species are known.
The few potential WNV vector species primarily breed in two types of places: stagnant water and high elevation salt marsh pools. The stagnant water habitats can be found in artificial containers such as bird baths, tires, buckets, kiddy pools, stormwater and catch basins, drainage ditches, etc. where water may not be regularly exchanged and becomes stagnant. Many of these containers can be easily emptied to eliminate mosquito breeding conditions.
The high elevation salt marsh pools refers to natural pools that are located above the normal high tide line. These areas are typically only flooded during significant storms or other extremely high tide events, often only once per month. Some of them contain fish that will act as natural predators, keeping the mosquitoes from surviving and breeding. Those pools without fish, however, provide mosquito breeding habitat.
The one potential EEE vector species breeds in some red maple and cedar swamps. Maine has many of these habitats and they too have natural predators.
It should be noted that some species that currently do not carry WNV or EEE in Maine could become vectors over time. Therefore, it is important to continue to learn about the role of mosquitoes in the spread of the virus.
Basic information on mosquito ecology (off-site).
Go here for information on preventative actions you can take.
