Restoring wetlands has a foreseeable and inevitable downside: the creation of mosquito habitat.
Breeding disease-transmitting mosquitoes isn't just a surprising side effect of creating wetlands, but an inevitable and foreseeable consequence that must be acknowledged when planning wetland restoration projects, said Elizabeth Willott, an assistant professor in the department of entomology at the University of Arizona in Tucson.
Wetlands do have benefits for people, she said. "Wetlands clean water, help in flood control, provide habitat and have aesthetic value." Even so, she said that environmental ethics require taking into consideration that after a wetland is restored or created, people's exposure to mosquito-borne diseases may increase.
To realize the impact that mosquitoes can have, just consider the mosquito-borne West Nile virus. In just a few years, West Nile virus, first found in the United States in New York, has already spread as far as Washington state and Arizona.
Diseases transmitted by mosquitoes, such as malaria, encephalitis and West Nile virus, can be just one bite away. In the 1800s, when Tucson's now-dry river beds had water more regularly, malaria was present in the Tucson basin.
Although malaria is not present in the Tucson area now, Arizona's West Nile virus season has already begun.
"Several obstacles block people from frankly discussing mosquito problems," writes Willott in her paper "Restoring Nature, Without Mosquitoes?" The article will be published in the June issue of Restoration Ecology.
The short-term nature of funding is one problem. Another is the fear that bringing up negative aspects of a wetland restoration project makes it more likely the project will be rejected. However, Willott suggests that a proposal is strengthened by explicitly addressing mosquito control.