Mosquitoes: Friends and Foes?

Published in Better Ways

Setting the record straight with a balanced view about mosquitoes and their place in the natural chain!

Mosqutio Mosqutio Photo: Sondre Dahle (reproduced with permission)

About mosquitoes

There are over 3,500 species of mosquito, with more being found in great numbers all the time round the world. Mosquitoes, like flies, belong to the order named Diptera, because they have two wings. They belong to the family Culicidae and are classified in two main mosquitoes as pollinatorsgroups, Culicines and Anophelines.

Mosquitoes develop from eggs into worm-like larvae, which transform into pupae with a hardened outer skin, emerging in the end as fully formed male and female mosquitoes. Not long after emerging, once they have developed enough strength to fly adequately, the mosquitoes mate, after which the males die. The females feed up before laying their eggs, either on blood or nectar or sap, depending on the species. The eggs are laid in fresh, brackish or salt water, whether clean or polluted. Any standing water can be home to mosquito eggs, whether a natural pool, water butt or water collected in old car tyres or ruts in ditches, to name just a few. Culex mosquitoes lay their eggs in compact clumps, while the Anopheles group lays its eggs singly. Eggs can take just a few days or up to several months to hatch. The larvae which develop from the eggs mostly breathe at the surface of the water; some feed near the surface, while others find food deeper down. The larva transforms into a pupa, still living in the water, but no longer feeding. The adult mosquito comes out of the pupa and into the air after two to seven days, depending on circumstances. The whole life cycle takes between two and four weeks.

What are mosquitoes good for?

Mosquitoes suffer from a bad press, but they are not all bad!

- mosquito larvae in freshwater habitats help to purify the water by eating detritus: they have tiny brushes in their mouths which beat to create currents bringing in food particles, which are then transferred into their bodies

- some mosquito larvae feed on other insects

- mosquito larvae are food for dragonfly and damselfly larvae (nymphs), which live in their watery habitats for between two and six years, during which time they can consume enormous amounts of mosquito larvae as well as other small insects

- mosquito larvae are a food source for freshwater fish such as trout, perch, mosquitofish (gambusia affinis and gambusia holbrooki) and guppies (poecilia reticulata)

- killifish are small fish which eat developing mosquitoes in the egg, larva and pupa stages: when their numbers are highest, mosquito populations are greatly reduced. There are different types of killifish, which can live in fresh, brackish and salt water.

- adult mosquitoes are food for other species, notably bats, dragonflies, damselflies and insectivorous birds such as bee-eaters, all of whom have a voracious appetite for mosquitoes

- mosquitoes have a role in pollination: they feed on nectar (not just blood) and so can transfer pollen from plant to plant, as has been described in Norwegian researches; the North American Blunt Leaved Bog Orchid (Platanthera obtusata) provides a specific example

- the diverse roles and activities of mosquitoes, including night-time pollination, are being extensively researched, especially at the Smithsonian Institute in North America

Mosquitoes as pests

Mosquitoes are generally disliked and even hated by humans, because they bite. Mosquito bites can cause reactions ranging from mild irritation to severe allergic discomfort and, in some cases, disease. It is estimated that only about 3% of mosquito species carry zoonotic diseases (i.e. diseases which are dangerous for humans), but because of these, mosquitoes as a whole are targeted for annihilation in many countries, including Croatia.

In the HZJZ Yearbook for 2020 (in Croatian), where the figures for infectious diseases are given in item 5 'Zarazne bolesti u Hrvatskoj', malaria cases are given as 5 (imported); dengue fever cases: 3 (imported); West Nile fever: 0; Zika virus: 0. So the incidence of mosquito-borne diseases in Croatia is negligible, despite the rise in mosquito numbers reported in the initial monitoring, and the presence of potential disease carriers noted over the years.

Mosquito species as potential disease carriers which have been identified in Croatia according to factsheets issued by the European Centre for Disease Prevention and Control.

Aedes albopictus (Asian tiger mosquito): can carry dengue fever, chikungunya virus, dirofiariasis. This mosquito has been monitored in Croatia since 2016 (link in Croatian).

Aedes japonicus (East Asian bush or rock pool mosquito): possibly could become a transmitter of diseases such as West Nile fever, but is not considered a definite vector for disease transmission. Monitoring in 2016 and 2017 revealed that it was spreading in Croatian territory.

Anopheles atroparvus: can transmit malaria; possibly associated with West Nile fever. This species has been identified in Croatia.

Anopheles labranchiae: can transmit malaria. This species has been identified in Croatia.

Anopheles plumbeus: can transmit malaria. This species has been identified in Croatia.

Anopheles sacharovi: can transmit malaria. This species has been identified in Croatia.

Culex pipiens: can transmit West Nile fever and Usulu virus; possibly could transmit various other viruses. This species has been identified in Croatia.

Self-protection against mosquitoes

Note: the suggestions given here are based on the wide variety of personal experiences, including our own, which people have shared over the years. Always make sure that you do not use any substances, whether natural or chemical, in any way which can cause incidental harm to yourself, others, animals or the natural environment. Bear in mind that some essential oils are toxic to pets. If in doubt, seek professional advice. We accept no responsibility for misuse of the information we are sharing.

Personal protection

- Many foods create smells in our bodies which mosquitoes apparently don’t like, including garlic, onions, vinegar, chili peppers, lentils, beans and tomatoes, so eating them may help to repel mosquitoes.

- Many people find that taking a vitamin B supplement reduces the effects of mosquito bites, and indeed may make one less prone to get bitten.

- Avoid or at least limit alcohol, as drinking alcohol causes our bodies to release more carbon dioxide than normal, which attracts mosquitoes.

- Mosquitoes are attracted to lactic acid, which is produced when you sweat, and even from eating salty food: bathe or shower frequently if you are prone to sweating.

- Wear light-coloured clothing: mosquitoes are apparently attracted to darker colours.

- Using a fan may help to keep mosquitoes away from you.

- Natural repellent sprays which may help to protect your skin can be made from various essential oils individually by adding a few drops of the chosen substance to water in a spray bottle. Some essential oils can be mixed together for more potency: you can find numerous examples of homemade sprays on the internet and in herbal books. Always heed precautionary advice. In particular test a small area of your skin for allergy before applying any new concoction more generally on your body. Do not apply sunscreen before or after spraying your skin with an essential oil solution.

- Suitable scents which mosquitoes hate include tea tree oil, peppermint oil, mint oil, lavender oil, neem oil, citronella oil, tulsi (holy basil, ocimum sanctum) oil, lemon eucalyptus oil, cedarwood oil, lemon grass oil, castor oil, and cinnamon oil among others.

Around the home

- Use mosquito screens over windows, also nets around beds if possible.

- Do not leave lights on inside your home in the evening with the windows and doors open.

- Cloves and lemon: slice some lemons in half, insert cloves into each half and spread them around your home.

- Essential oil sprays can be applied round your home as well as to your skin.

- A garlic spray made by crushing some garlic cloves and boiling them in water, when cooled, can be applied around the home.

- A mixture of apple cider vinegar and witch hazel in equal quantities can be an effective anti-mosquito spray round the home.

- Candles scented with essential oils such as citronella can deter mosquitoes.

Outdoors

- Many birds feed on mosquitoes and other insects, so attracting them into your garden or on to your balcony can help control mosquito numbers.

- Never leave standing water in any kind of container (eg pots, old tyres), as these are ideal breeding grounds for mosquitoes. Spreading coffee grounds in puddles or stagnant water kills the mosquito eggs.

- Some plants repel mosquitoes, including basil, mint, feverfew, rue (ruta graveolens and ruta chalepensis), citronella and catnip, so they are good to plant in the garden or in pots around the outside of your home. (Note: some of these plants are skin irritants and can cause allergic reactions: They can also be very harmful if ingested by people or animals, so take care to keep them out of reach of very young children or puppies!)

- If you use an outdoor barbecue in the summer, burning some sprigs of rosemary or sage on it will help repel the mosquitoes.

Killing mosquitoes

In Croatia, measures to control mosquitoes were introduced several years ago. The Insect Control Programme has descended into a system of mass extermination of insects of all kinds using poisons which are potentially dangerous not only to the insects but to animals and humans. The result has been disastrous collateral damage. Mosquitoes have flourished while their natural predators have been decimated.

Extermination programmes using chemical pesticides don't work!

Many people use chemical insecticides in the home, without realising the potential harmful effects they might have on human health and the environment. You can check on the possible ill-effects of the active ingredients in many chemical insecticide products using our reference list ‘Pesticides and their Adverse Effects’.

A 'mozzie-swiper racket'. Photo Vivian Grisogono, courtesy of Nada Kozulić

We do not recommend killing insects, especially not with poisons. However, if you feel you have to, natural alternatives to chemical insecticides include garlic, camphor, pyrethrum and apple cider vinegar. and electronic mosquito-zappers. A very effective, simple way to put a stop to mosquitoes buzzing irritatingly around you is to use a special 'mozzie-swiping racket' which kills on contact with its steel mesh construction - and does not require any special tennis skills to do its job!

The 'mozzie-swiper' metal mesh 'strings. Photo Vivian Grisogono, courtesy of Nada Kozulić

Information compiled by Nada Kozulić, Nicholas Haas and Vivian Grisogono, 2022.

NOTE: Many thanks to Sondre Dahle, senior engineer at the Norwegian Institute for Nature Research for permission to use his mosquito photograph. You can read about his researches in this interview.

You are here: Home about animals Better Ways Mosquitoes: Friends and Foes?

Eco Environment News feeds

  • Researchers say problem could increase number of people at risk of starvation by 400m in next two decades

    The pollution of the planet by microplastics is significantly cutting food supplies by damaging the ability of plants to photosynthesise, according to a new assessment.

    The analysis estimates that between 4% and 14% of the world’s staple crops of wheat, rice and maize is being lost due to the pervasive particles. It could get even worse, the scientists said, as more microplastics pour into the environment.

    Continue reading...

  • Annual survey by IQAir based on toxic PM2.5 particles reveals some progress in pollution levels in India and China

    Nearly every country on Earth has dirtier air than doctors recommend breathing, a report has found.

    Only seven countries met the World Health Organization’s guidelines for tiny toxic particles known as PM2.5 last year, according to analysis from the Swiss air quality technology company IQAir.

    Continue reading...

  • Tetrodotoxin immobilises the female – who is about two to five times bigger than the male – so mating can occur, researchers observed

    Male blue-lined octopuses inject females with venom during sex, paralysing their larger mates to avoid being eaten, new research has found.

    The blue-lined octopus is a tiny, highly dangerous cephalopod found commonly in shallow reefs and tide pools.

    Continue reading...

  • US-style mega-farms in Herefordshire face tough new regulations after high court ruling

    Industrial poultry farms face tough new regulations around the disposal of chicken manure after a judge ruled it can be classified as waste and requires a detailed and transparent plan to dispose of it without damaging the environment.

    The high court ruling means new US-style mega-farms in Herefordshire will have to deal with poultry manure as if it was industrial waste.

    Continue reading...

  • Campaigners to argue in court of appeal that plan is not in public interest and special administration is best option

    Environmental campaigners will challenge the granting of a high-interest £3bn emergency loan to struggling Thames Water at an appeal on Tuesday, arguing the “eye-watering” costs for a short-term fix are not in the public interest.

    With protests planned outside the court of appeal, Charlie Maynard, a Liberal Democrat MP who represents the campaigners, will argue in a three-day hearing that the public and consumer interest is not served by the debt package, which comes with a bill of almost £1bn in interest payments and financial adviser fees.

    Continue reading...

  • Blackamoor, South Yorkshire: They manage to lift the day out of dank drabness, accumulating in crazy formations, almost completely covering one rowan tree

    In a sequence of grey mornings, this one was especially dismal. It was cold. The trees were dank and thick with mist, bark slick with moisture, whatever was left of last year’s foliage drooping wetly, the bracken not bronze but dun, sliming into the earth, spring’s promise unfulfilled. I dropped my chin into the collar of my jacket and started up the hill, eyes fixed on the uneven ground at my feet, marshalling enthusiasm.

    The change, when it came, wasn’t gradual but instantaneous, as though a child had laid a ruler across the landscape and drawn a line, colouring in below with nondescript browns but above it with dazzling white. Overhead, the cloud thinned from dark to milky grey, the watery sun appearing on the horizon as I climbed out of the valley’s warm bed of moist air on to the glittering moorland above. I found myself laughing, the day upended. Every tree and shrub was now coated in frosty geometric shapes, each one stacked madly on top of another.

    Continue reading...

  • The Guardianas del Conchalito ignored chants of ‘get back to your kitchens’, determined to protect the environment and create a sustainable shellfish operation

    Ahead of the small boat, as it bobs on the waters near La Paz in the Mexican state of Baja California, is a long line of old plastic bottles strung together on top of the waves. Underneath them are as many as 100,000 oysters, waiting to be sold to the upmarket hotels down the coast.

    Cheli Mendez, who oversees the project, pulls a shell up from below, cuts it open with a knife, and gives me the contents to try: a plump, tasty oyster. Mendez is one of a group known as Guardianas del Conchalito, or guardians of the shells, and theirs is the first oyster-growing business in the region run entirely by women, she says.

    The women dug a channel with shovels and pickaxes to allow seawater to reach the mangroves

    Continue reading...

  • An ugly fight has ripped through Galloway in south-west Scotland, with rival campaigns complaining of dirty tricks and murky finances. How could the mere possibility of a new national park stir up so much ill will?

    As soon as the green fields of Galloway, in south-west Scotland, were selected as the preferred site for Britain’s first new national park in 15 years, Denise Brownlee sprang into action. The 64-year-old retired civil servant had served two seasons as a park ranger in Loch Lomond and the Trossachs, and knew a thing or two about the chaos brought by thoughtless day-trippers and campers. “The detritus!” she says. “I’ve seen a two-man tent used as a human litter tray. You think dog poo on the pavement is bad? Try wandering up any remote little area in a national park. Your faith in humankind gets lost.”

    In July, Galloway was chosen as the frontrunner from a shortlist of five areas as part of the Scottish government’s pledge to designate at least one new national park – the country’s third – by 2026. The park’s creation, however, is by no means assured. The other areas in the running had faced varying degrees of opposition (especially Lochaber in the west Highlands), but no one could have predicted the ugly fight that was to tear through one of Scotland’s most picturesque regions, rip apart friendships and turn neighbours against each other.

    Continue reading...

  • Rainfall in Bahía Blanca led to 10 deaths, swept away vehicles, destroyed bridges and left areas underwater

    The city of Bahía Blanca in Argentina had a new rainfall record on Friday, after a recent heatwave. More than 400mm (15.7in) of rain was recorded in just eight hours, more than twice the city’s previous record of 175mm set in 1930, and roughly equivalent to a year’s worth of rainfall.

    The heatwave primed the atmosphere for heavy rainfall by creating high instability and raising humidity levels. Then on Friday, as a cold front swept across the region, this warm moist air was able to rise, cool and rapidly condense, leading to severe thunderstorms across the region. As the front then continued northwards towards Buenos Aires over the weekend, further severe storms were triggered, containing heavy rain, hail and strong gusts.

    Continue reading...

  • Two Italian cacti smugglers have been fined for illegally trading plants from Chile – and for the cost of restoring the environment. Conservationists hope more cases will follow

    Chile’s Atacama desert is one of the driest places on Earth, a surprisingly cool environment, sucked clean of moisture by the cold ocean to the west. This arid, golden landscape is home to many rare species of cacti, which attract professional and amateur botanists from around the world keen to make discoveries and experience the thrill of naming a new species.

    But they are not the only ones prowling the sands: Atacama has become a hotspot for succulent smuggling.

    Continue reading...

Eco Health News feeds

Eco Nature News feeds