This is a guest post by Dr Cameron Webb.
Love Australian wildlife? Fascinated by their ability to adapt to our diverse, often hard but incredibly unique habitats? Let me introduce to you the champions of adaptation, the humble, but often extremely annoying, mosquito.
There are hundreds of different mosquitoes in Australia. Some of them are locals, some of them are shared with our neighbours in South-East Asia and the Pacific, while others have accompanied travelers to our shores over the past couple of centuries. From coastal rock pools to alpine snow melt creeks, mozzies have found a home in almost every pool, pond and puddle across the country.
They’re a diverse group of creatures. Their life cycle is split in two with about a third of their life spent as wrigglers then pupae in the water, and the remaining two to three weeks as adults buzzing about and on the lookout for blood. But it’s only the females that bite. The blood provides an energy boost for egg development. The blokes mate and not much else - they’re lucky to live more than a week or so.
The need for blood means they bite us. Annoying enough as the biting can be, the possibility that these bites can make us sick is a major concern. Australia is generally free of the really nasty mosquito-borne diseases such as malaria, Japanese encephalitis and Zika, but we do see occasional local cases of dengue and our home-grown viruses, particularly Ross River virus and Barmah Forest virus causing around 5,000 cases of illness each year.
But they’re not just pests. Mosquitoes hold a fascinating place in our local environment. Here are either things to love (or at least begrudgingly respect) about mosquitoes!
1. They can fly a long way! While many of our backyard mosquitoes don’t fly much further than our neighbour's place, those in our coastal wetlands have been reported flying more than 20km inland. Scientists who mark these mozzies with fluorescent dusts have tracked their movements over many kilometres.
2. Salty water or fresh - no problem! While most mosquitoes love freshwater, some of Australia’s most common mosquitoes love living in saltmarshes and mangroves that are flooded by high tides. The saltier the water, the better it is for these mosquitoes. It’s just a shame we’ve got to share the coast with them.
3. Mozzies are snack food for bats! Many have asked what “good” a mosquito could possibly do and scientists answered this recently by studying the diet of microbats. These small insectivorous bats prefer to eat moths than mozzies but that doesn’t mean they don’t chomp through plenty each summer. Mosquitoes may not have much more nutritional value than a fingernail but if you eat enough of them, they’ll provide a boost in energy. Just don’t expect bats to control mosquito populations - it won’t happen.
4. Surviving a decade of drought! Mosquito eggs are amazing. While many hatch quickly once laid, others can survive for months or years, remaining unhatched inside water-holding containers and in cracks and crevices around our local wetlands. A decade of drought ravaging our waterways across inland regions of the country wasn’t enough to kill off these mosquitoes, and following the flooding of the past couple of years, they have re-emerged in record numbers.
5. Crabs in your bed? No worries! There are some mosquitoes in northern Australia that have moved into crab holes along the coast. These water-filled muddy holes are perfect for escaping the ebb and flow of daily tides and probably provide a neat hiding place from hungry fish.
6. Bright orange and far from boring! Most mosquitoes are probably considered drab but many are adorned with bright, iridescent scales and elaborate patterning. But the most beautiful are some of the bright orange mosquitoes that are so distinctly different that they stand out like a beacon amongst others.
7. Mozzies are home to harmless viruses! While we’re concerned about mosquito-borne pathogens that pose a risk to human health, scientists are now discovering a world of viruses living in mosquitoes that pose no risk to humans. These ‘insect specific viruses’ live in the mosquito and, one day, may even be able to help stop the spread of more serious viruses through their use as a 'mozzie vaccine', as when they’re present, they can block other viruses from infecting the mosquito.
8. Yum, let's suck up some ant vomit! Feeding on blood may make you feel icky enough but how about ant vomit? There is a mosquito in northern Australia that’s adapted to sticking its proboscis down the throats of ants instead of into the arms of people. The ants escape unharmed but the mozzies escape with a sweet meal.
You can purchase a copy of Cameron's book by following this link.
Dr Cameron Webb is a Medical Entomologist with NSW Health Pathology and University of Sydney. He is lead author of A Guide to Mosquitoes of Australia (CSIRO Publishing) and can be followed on Twitter (@mozziebites) for all the tips and tricks on avoiding mosquito bites this summer!
Banner image courtesy of Stephen Doggett.
This article has been co-published by Wild Melbourne and Andrew Isles Natural History Books.