Why Do Mosquitoes Exist? Are They Useful?

Have you ever wondered why mosquitoes exist and if they serve any useful purpose? You might think that they are here just to annoy us or spread diseases. But they might have their place in the ecosystem, they might serve some useful purpose.

From a human point of view, they are a big nuisance. Causing us to stay indoors on lovely summer evenings, wear long sleeves and long trousers when it’s hot or make us put on some sticky unpleasant repellent.

For mosquitoes, their purpose is to live as long as possible and lay as many eggs as possible.


Diseases Transmitted By Mosquitoes

Besides being a nuisance, mosquitoes cause hundreds of thousands of deaths every year. According to the World Health Organization (WHO), malaria alone caused 438,000 deaths in 2015, in 2000 this figure was 839,000!

It’s not only humans that are affected by the diseases spread by mosquitoes. Other animals such as dogs and horses are also affected.

Besides malaria, there are many other diseases transmitted by mosquitoes, here are a few: Chikungunya, Dog Heartworm (can be a life-threatening disease for dogs) Dengue, Yellow Fever, Eastern Equine Encephalitis (infects horses and humans),  West Nile Virus and Zika Virus.

In addition to these diseases, mosquito bites cause an allergic reaction. The body’s immune system reacts to the mosquito’s saliva, which causes irritation. This is the main reason most of us hate mosquitos.


Mosquitoes Must Be Useful For Something

The main positive reason for mosquitoes existing is the role they play in the food chain of other animals.

Mosquito larvae provide an important food source for small fish, frogs and tadpoles, and other insects. If they lose this food source their numbers may suffer. Then anything that feeds on these small fish or insects, such as larger fish or birds could also suffer.

Adult mosquitoes provide a food source for birds and bats. But researchers suggest that if they weren’t around the birds would find other insects and probably wouldn’t suffer.

Adult mosquitoes feed on nectar, in fact, it is the sole diet of the males, so some plants might suffer from a shortage of pollinators.


Would Nature Suffer From Having No Mosquitos

An article in Nature magazine from 2010 asked scientists what they thought would be the result of eliminating mosquitoes. Most thought there would be very little difference and the ecological void would be filled by other insects or organisms.

The one area where there might be a problem is in the Arctic Tundra. Some scientists think the number of migratory birds that nest in the region could fall by 50% or more without having mosquitoes to eat. There are other researchers that disagree and say it wouldn’t make any difference.

The path the Caribou take could also be affected, they are thought to take a path to avoid the swarms of mosquitoes. If they change their route, the Arctic valleys, through which thousands of Caribou pass, would have their ecosystems changed. So there might be some effects in the Arctic!

So according to most scientific opinion mosquitoes could be eradicated without having a long term effect on the ecosystems where they are active. The problem is no one really knows what would replace them, it might be worse or better.

If there was a will to wipe them out, just think of the ecological damage, draining swamps and ponds, treating wide areas with insecticides. It would cause an ecological disaster and could only be considered in limited areas. And only if there was a really serious health risk.


Humans Would Profit

We would profit from having no mosquitoes. There would be less disease so there would be more people on our wonderful planet. Many lives would be saved and many would escape illness brought on by mosquitos born diseases. This would mean less burden on the health services, particularly in poor countries.

With all the humanitarian and economic advantages of eliminating mosquitoes, it’s the limitations in the way we kill mosquitoes that mean a mosquito free world isn’t for anytime soon.

Although mosquitoes don’t seem to serve any useful purpose, we can’t eliminate them without doing damage to other useful species. So we will have to carry on with our limited methods of control and the use of repellents.


Leave a Comment