A July 31 virtual news conference sought to shed light on Florida’s recent saltmarsh mosquito onslaught.
A panel of experts, including scientists and representatives from the Florida Mosquito Control Association, explained the nesting patterns of the particularly aggressive Aedes taeniorhynchus mosquitoes, which can hatch in the billions per acre of marshland.
“Typically, this mosquito is the most plentiful of more than 45 species routinely found in the Keys because it favors marshes, mangroves and wetlands, which we have in abundance,” said Chad Huff, the Florida Keys Mosquito Control District’s public education and information officer.
“The females do not lay their eggs directly into water; they lay their eggs in moist soil,” said Eva Buckner, assistant professor from University of Florida IFAS.
This year’s weather patterns fostered a perfect storm for the mosquitoes, allowing for a population explosion which is one of the worst in decades. Mostly dry months earlier this year allowed many ponds to dry up, creating moist but non-aquatic environments needed for the females to lay eggs, which hatched with June’s heavy rainfall and spring tides.
Last year’s hurricanes may have similarly contributed adverse effects, as hurricanes can alter the landscape of salt marshes, creating more or less open soil for the mosquitoes to breed in.
“Trained FKMCD field inspectors have located and identified many new saltmarsh mosquito production sites in locations that have never been favored before by female mosquitoes looking to lay their eggs,” Huff said.
In the Keys, tidal waters have also been especially impactful in producing an explosion of mosquito populations.
Saltmarsh mosquitoes are known for their aggressive nature and long flight range, which has led to this year’s population boom impacting all parts of the state, and not merely local environments.
Fortunately, the saltmarsh mosquito is not considered to be a serious vector for transmitting human diseases, although they pose a potential threat to pets as possible vectors of heartworm.
“The biggest issue caused by salt marsh mosquitoes is going to be that nuisance factor,” Buckner said. Allergic reactions are another potential risk, and scratching bites may enable secondary infections.
Mosquito professionals monitor weather patterns to pursue an initial “source reduction” approach, preventing them from laying eggs in the first place. As larvae, the populations are easier to limit than those of flying mosquitoes, and larvicide has a limited impact on other organisms.
As adulticides can potentially kill other insects, measures are always taken to spray when pollinators are not active and the wind is low.
“All mosquito control programs use an integrated pest management program,” said Buckner. “There’s not just one tool to control mosquitoes.”
“As of early August, the mosquito numbers have reduced considerably throughout most of Monroe County, thanks to the extremely hard work by a dedicated team,” Huff said.
Mosquito control officials encourage residents to mow their yards and drain standing water, which can provide habitats for container mosquitoes. Residents are encouraged to contact their local mosquito control boards, who may send inspectors to address any potential concerns.
