The sunbaked, arid conditions of the desert are a far cry from the aquatic habitats in which mosquitoes usually thrive. Yet, even in the driest and dustiest parts of the planet, mosquitoes can still emerge.
The world’s least favorite (and most dangerous) biting insects are most commonly found in areas with abundant water sources, such as around ponds, lakes, and anywhere else with standing or stagnant water. The reason for this lies in the way they reproduce, as mosquitos spend the first, larval stage of their life underwater and their eggs only hatch when completely submerged.
So, how do they manage to reproduce in the desert?
Mosquito life cycle
To understand how mosquitoes can weather such wildly different climates, you must first understand the various stages (and requirements) of their life cycles.
The mosquito life cycle is divided into four distinct stages: the egg, larvae, pupae, and adult.
Until recently, it was widely believed that mosquitoes would only lay their eggs in standing water or on moist surfaces. Mosquito eggs won’t hatch until they are completely submerged by rising water (usually as a result of rainfall, snowmelt or floodwater) and can survive for long periods of time in the interim.
However, a new study published in the Journal of Entomology recently reported that some mosquitoes (namely those of the Culex genus) actually lay the vast majority of their eggs on solid surfaces.
The larval stage of the mosquito life cycle lives exclusively in water. Once the eggs are submerged, they hatch and the larvae (also known as wrigglers) to feast on tiny, organic particles in the water (such as algae, plankton, and fungi).
Mosquito larvae go through four developmental periods (instars) during this life stage, getting slightly bigger each time.
Once they reached their fourth and final instar, mosquito larvae molt into their pupal stage. Though still active during this stage, pupal larvae don’t eat. Instead, mosquito pupae (aka tumblers) hang out at the surface of the water until, after a few days, they emerge into the final, adult stage of their life cycle.
The fourth and final stage of the mosquito life cycle is the flying insect. In this stage, the females feed on the blood of other animals to develop their eggs.
How do mosquitoes survive in the desert?
The secret to survival for mosquitoes in the desert lies in the various stages of their lifecycle, and how each survives in the external environment.
Though the larval and pupal stages of the mosquito life cycle are dependent on water for survival, the eggs are much hardier and can survive the arid conditions of the desert for a lot longer.
Studies into the breeding habits of Aedes aegypti (a mosquito species that originated in the dry climate of Africa) found that eggs laid in non-aquatic environments can dry out and remain dry for months. When the monsoon rains finally do arrive, the eggs are submerged and finally hatch after a period of months or even years. This allows mosquitoes to survive in areas without regular rainfall and explains why thousands of mosquitoes may suddenly emerge at the end of a period of drought in deserts.
Do mosquitoes live in the desert year-round?
Mosquitoes are most commonly seen in the desert around periods of seasonal rainfall when parched riverbeds and basins start to fill up again. This submerges the dried-out mosquito eggs that have been deposited in and around these potentially-aquatic environments, and a new batch of adults emerges.
These seasonal emergencies may make it seem like mosquitoes only live in the desert during certain seasons but, in fact, they are there year-round. Mosquito eggs are much more resistant to drought than any other stage of the life cycle and can withstand the harsh conditions of the desert until there is enough water for them to survive in their larval form.
How can you get rid of mosquitoes if you live in a dry climate?
People living in hot climates with limited rainfall may think they can escape the worst of mosquito season but, unfortunately, some species survive very well in dry, urban areas.
Aedes aegypti and Aedes albopictus are two species that are widespread throughout the southern states of the US. Aedes aegypti, in particular, can survive and breed in areas with very little water and is also a known vector for a wide range of potentially serious illnesses.
With no lakes or ponds nearby, you may be wondering how it’s possible for mosquitoes to invade your yard and house, but finding and removing their breeding grounds is simple.
Watering cans, blocked drains, plant pots or even a forgotten glass of water can all become potential egg-laying sites for mosquitoes, so emptying out all standing water sources around your home is a great start.
You can also avoid being bitten by mosquitoes by:
- Sleeping under a mosquito net.
- Installing screens around windows and doors in your home.
- Wearing a mosquito-repellent spray in the evenings.
- Dressing in light, loose-fitting clothing that covers your arms and legs.
- Installing fans (as many mosquito species are weak fliers and won’t be able to move through a high wind).
- Using oil burners, candles, and reed diffusers to infuse to air with mosquito-repelling essential oils (like citronella and lemon eucalyptus).
Mosquitoes are known for their love of aquatic environments and rely on water to reproduce. The larval and pupal stages of their lifestyle must be carried out in aquatic environments, and eggs must be fully submerged with water before they can hatch. So, how do desert mosquitoes survive?
The answer lies in the egg form of their life cycle, which is far more resistant to drought than any other phase of their development.
Prior to popular belief, certain species of mosquitoes lay their eggs primarily on dry land, rather than in standing water sources. In a desert environment, these eggs quickly dry out but are still able to hatch when the rain finally falls, even if they have to wait months (or even years) for this to happen.