Why march flies will never give up on you
Bec Crew
Bec Crew
That sounded weird… let’s rewind a bit.
There are more than 200 species of march flies in Australia and they’re mostly found around water sources such as creeks, estuaries and mangroves. Like mozzies, they’re attracted to blood, but they’re larger than mozzies and way more aggressive.
And they don’t just sneak a sip of blood and leave their victims with an irritating itch – they slash, pierce and suck with painful precision, their tiny mouthparts cutting like razor blades through flesh.
In Australia and New Zealand, it is flies from the family Tabanidae we call march flies (this differs in other countries). Tabanidae will target anything warm-blooded with a pulse, whether it’s a human, a cow, a horse, a kangaroo, or yes, even a saltwater crocodile. They go for any weak spot, which is in short supply on a crocodile, but don’t worry – march flies are perfectly happy to go for the eyelids if they have to!
When I say “they”, I mean the females. To them, blood is essential, because it provides the proteins and nutrients they need to develop eggs and produce the next generation. It’s why they’re so tenacious: they simply cannot afford to be without a bloodmeal.
The males, on the other hand, are nice little pollinators, which makes this a real yin and yang situation. While the females are out there making an absolute menace of themselves, the males are feeding on nectar and pollen, such as from avocado flowers. Which, given the decline of native bees in Australia and elsewhere, is actually very handy.
It’s no mean feat avoiding the bite of a march fly. They can penetrate light fabrics, and repellent isn’t all that effective. David Yeates and Keith M. Bayless from the CSIRO’s Australian National Insect Collection recommend wearing heavy fabrics, such as a rashie. And, oddly enough, wearing vertical stripes might be a good strategy – recent research has found that stripes confuse march flies, which could explain why zebras look the way they do!
For some people, a bite can cause a serious allergic reactions, which could require hospitalisation, so anything you do to protect yourself is worth it.
If you’re wondering which parent the march fly babies take after, let’s have a look at what Yeates and Bayless say about them: “Covered in warty armour and fleshy tubercles, these maggots are voracious predators of soil fauna. To subdue their prey, they have long fangs with venom canals.”
Right.
At least the bitey little baby bullies prefer to stay in the soil.
