In December of 1865, shortly after the close of the Civil War, George F. Thompson visited Charlotte Harbor and wrote in his journal the following entry on his encounter with local mosquitoes:
“At dusk cast anchor near an Island about 7 miles from mouth of Peace Creek (in Charlotte Harbor). Here we were attacked by Musquitoes (sp) at first by Brigade then by Division and afterwards by Corps and doubting our ability to withstand their charges we concluded it would be wiser to retreat. Consequently we fell back about two miles and passed a miserable night in the boat.”
Thompson was in the harbor in connection with his role as an Inspector for the Bureau of Refugees, Freedmen, and Abandoned Lands, the federal agency charged with the task of overseeing Reconstruction in a non-slave South.
Patrick D. Smith, in his excellent 1984 novel In a Land Remembered, describes the horrors of clouds of mosquitoes attacking the cattle droving family chronicled in his book. Both stories resonated with me one evening while venturing out just after sunset and encountering an onslaught from a small horde of skeeters (not to be confused with the also annoying no-see-ums). It occurred to me that, despite interacting with them most of my life, I knew relatively little about this annoying insect.
Discussing the topic with our son-in-law who is a doctor I was surprised and disturbed to learn that mosquitoes are believed to have been responsible for close to half of all human deaths since the evolution of man. Curious to learn more, I signed out military historian Timothy C. Winegard’s 2019 book The Mosquito: A Human History of our Deadliest Predator which confirmed this macabre assertion within the first two pages. I love reading (and writing) about both nature and history so this book drew me in from the first chapter. Winegard’s approach was to present a military history of the world as influenced by the strategic role of the mosquito, its habitat and the diseases it transmits. He recounts the campaigns of ancient Greece and Persia, Alexander the Great, the Roman Empire, Attila the Hun, the Crusades, Genghis Khan, the Columbian Exchange as well as many of the principal conflicts of the last five hundred years. His theories on how the mosquito and the diseases it carries have influenced the course of human history are both stunning and thought provoking, even attributing much of the success of the American Revolution to the diminutive mosquito.
Scrutiny under a macro photo lens reveals that there are a startling variety of shapes, coloring and sizes of the different species which are sometimes further categorized by their habitats and whether salt or fresh water breeders. There are about 12 genera and 150 species of mosquitoes found in the USA. Only a few of these are carriers of diseases and the balance might more succinctly be described as simply nuisances. The most annoying ones can be safely referred to as “her” as only the female bites! The telltale buzzing sound they emit results from the female beating her wings at a frequency of a thousand times per second, intended to attract males for copulation.
Charlotte County, Florida Mosquito Control claims there are 40 varieties in its area of interest and provides helpful descriptions and accompanying photos of the main species on their website (https://www.charlottecountyfl.gov/services/mosquitoaquatic/Pages/Most-Common-Mosquitoes.aspx).
Aedes taeniorhynchus, aka Black Salt Marsh Mosquito – Photograph by Sean McCann [used with permission]
It was only in the 1880s that the connection between mosquitoes and disease was firmly established. Prior to that time humans were aware of the association of stagnant water and its smell with the spread of disease so blamed the air and called it miasma. The word malaria derives from the Italian expression for “bad air”. Of the many different diseases which have been associated with mosquitoes, most are carried (vectored) by a single type. Species within the genus Anopheles carry malaria while the Aedes genus can carry yellow fever, dengue, encephalitis, chikungunya or Zika. West Nile disease is most commonly associated with the genus Culex.
While some commentators have claimed that mosquitoes are an important element in the diet of bats, frogs and grasshoppers, most studies have concluded that they are a miniscule portion of the diet of any of these.
In 1939 DDT was discovered to be an effective pesticide for the control of mosquitoes and was widely deployed for the next 30 years. Disease rates dropped dramatically wherever it was sprayed. By 1972 when DDT’s use was banned in the USA due to the negative impact it had on other species, the mosquito had already adapted genetically to make it largely ineffective. Manufacturers continued to export it to other parts of the world for the following ten years. A similar story emerged with respect to various antidotes to malaria such as quinine and other synthetic substitutes. Usually within a short number of years mosquitoes found ways to evolve resistances to each new drug. The newest frontiers in the battle with mosquitoes are male sterilization efforts and gene altering experiments (CRISPR) which, while showing promise, raise ever more ethical and scientific issues to ponder.
Most Florida snowbirds are spared the worst of the mosquitoes’ reign of terror as these insects are relatively dormant during the dry winter months. Man has also worked hard to manage the risk through the construction of drainage ditches to eliminate standing water and of course the essential screened-in lanais which we hide behind. Much of the effort of the local Florida mosquito control boards (established under Florida Statutes Chapter 188) are directed at education, eliminating mosquito habitat and selective spraying of worrisome populations. The Lee County Mosquito Control District receives approximately 2% of our property tax dollars to help in this effort while Charlotte County seems to get by with much less.
The best advice I have seen for managing your exposure to mosquitoes is to eliminate standing water near your home, wear protective clothing and socks when out in the evening and consider the use of effective repellants such as DEET.
This article was first published in the December 2020 issue of the BSM Beacon.