Cattail Mosquito | Fact Sheet

Ever wonder why even after getting a mosquito service, you still get annoying mosquitoes right at dark that bite for an hour and go away? Well in North America, one particular mosquito out of the thousands that are around are pretty much impossible to control. The common name used for this type of mosquito is cattail mosquito and it refers to the species Coquillettidia perturbans (CP).

This species is common throughout about 2/3 of the United States (exception being the Rocky Mountains and parts of the desert Southwest). CP is also native in Canada from the Atlantic to Pacific along the US/CDN border and for a few hundred miles north.

CP is described as a permanent freshwater mosquito requiring natural freshwater swamps, and wetlands with emergent aquatic vegetation (example: cattails). CP is a significant human health threat in that they are competent vectors of West Nile Virus (WNV) and Eastern Equine Encephalitis (EEE).

Cattail Mosquito Life Cycle

CP is unusual (and difficult to control) due to the way the immature stages (larvae and pupae) obtain oxygen. Unlike most other species that have a structure known as an air horn at the distal (far) end of their bodies, which works like a snorkel to acquire oxygen from the atmosphere, CP larvae’s abdomen end as a thorn-like structure.

The CP larvae and pupae pierce the very small hollow roots of aquatic plants and utilize the oxygen found inside the plant structure. CP larvae and pupae do not have to swim to the surface of the water at any time during their immature development. This adaptation makes CP larvae and pupae difficult to control with larvicides (regardless of active ingredients) as they typically have very little, if any exposure, to the products as they are normally applied. CP larvae and pupae, if disturbed, can detach quickly from their host plant and swim down into the sediment of the body of water to hide. They will return to the plants when the disturbance stops.

In southern regions, there are typically two or three generations per year. In northern regions, only one generation occurs per season with larvae being the overwintering stage. Adult CP emerge in early to mid-summer with peak abundance in mid-summer through September.

Females live longer than males. Both males and females utilize plant nectars as carbohydrate-containing food. Only females will seek blood hosts to successfully produce eggs. CP adult females are aggressive biters but are not considered true day-biters. Blood-seeking by adult females typically occurs soon after sunset but tails off as the night progresses. Swarming behavior around hosts can be very persistent. Day biting can occur if suitable blood hosts are available while in heavily shaded resting sites. CP are strong fliers and will travel great distances up to 10 km or 6 miles to find blood hosts. However, they are transient, very rarely resting in the same area for extended periods. CP adult females will feed on virtually any warm-blooded animal, including humans.

Cattail Mosquitoes are Extremely Difficult to Control

Despite our best efforts, barrier treatments with residual insecticides are not as effective as with other mosquito pest species. What makes them so difficult to control is they are not physically present when we make our applications and do not habitually rest in areas where residual insecticides are placed to control other species.

Unfortunately, it’s not a question of whether the control product is ineffective, it’s the fact that the mosquito is not there when the spraying takes place. If they were, it would control them the same way other mosquito species are eliminated. Also, because they fly in from long distances, they are very strong fliers which allow them to fly above, around, and most importantly without touching or landing on the treated plant materials.

CP does not habitually rest in areas where residual insecticides are placed to control other species. Larvicides are not generally effective in reaching immature CP in quantities that result in mortality regardless of active ingredients. Removal of supporting aquatic plants will help reduce numbers and biting pressure if allowed and practical.

If you have any further questions about Mosquito Hero or mosquito control, please feel free to contact your local Mosquito Hero professional.