Harris County Precinct 4 is breeding and releasing native “mosquito assassins” as part of its ongoing efforts to curb its nonnative mosquito population.
The precinct’s Biological Control Initiative, established in 2012, is conducting studies at the Houston Museum of Natural Science Cockrell Butterfly Center to observe the effects of releasing organisms that feed on mosquito larvae on controlling mosquito populations.
They are currently on their fifth release, BCI Director Anita Schiller said.
“We are collecting data to evaluate the predators’ efficacy and hopefully demonstrate that this works,” Schiller said. “It is a novel approach to use a native organism, a native predator, against an exotic species.”
The initiative targets two nonnative mosquito species: the yellow fever mosquito and the Asian tiger mosquito. Because the species were "accidentally imported," they lack natural predators to keep their populations in check, Schiller said.
The mosquitos are prevalent in Precinct 4 in residential areas with lush landscaping or backyards or located near wooded areas, she said.
“They are really only found where there are people,” she said.
The scientific name of the mosquito assassin is Toxorhynchites rutilus, which is harmless to humans. Besides the mosquito assassins, other organisms of interest at the BCI include small roundworms that infect and kill mosquito larvae, aquatic carnivorous plants and dragonflies, and damselflies, according to the BCI’s website.
From March to October of last year, BCI completed field studies observing mosquito populations in four undisclosed locations in Precinct 4, Schiller said.
Two of the locations were baselines, meaning mosquito assassins were not released into the area, while mosquito predators were released in the other two. Then the populations between the baseline and treatments were compared.
BCI will attend Harris County Precinct 4’s Civic Adventure Day on Sept. 28 to educate the public on its research as well as encourage community involvement with the initiative. For instance, residents can sign up to become “citizen scientists,” adopt and release mosquito assassins, and help collect data of their own, Schiller said.
The event will be held at Collins Park, located at 6727 Cypresswood Drive, Spring, from 10 a.m.-2 p.m.
Schiller said community involvement is key to curbing the exotic, urban mosquito population. Residents can help by removing stagnant water on their premises and staying safe by using Environmental Protection Agency-approved bug spray, she said.
“Mosquito control is not just the governments’ role; it’s everybody’s responsibility,” she said.