The Green Medium is an Emerald Award-winning, youth-run blog that seeks to innovate how we discuss and inform ourselves on environmental concerns.

Oh no, Mosquito!

Hello readers! Hope your week is going well! Last post, I ended with a question:

Would it be such a disaster if we eliminated mosquitos and their ilk, and how are bugs doing?
 https://www.pinterest.com/pin/235805730460819010/

https://www.pinterest.com/pin/235805730460819010/

I think it’s safe to say we all hate mosquitos. They’re annoying, and they’re also such an excellent disease vector that they kill over 1 million people annually, making them humans #1 enemy [1]. In most places they don’t compose a very large portion of the biomass. In the Arctic though, they create thick black clouds which draw migratory birds[2]. If we killed all the mosquitos, couldn’t their role be filled by another species though?

One study in France tracked “House Martins” after using pesticides that selectively eliminated mosquitos in the area. They found the Martins in the affected area laid on average 2 eggs compared to 3 in the control group. There are also some species, such as the “mosquito fish”, which depend heavily on mosquitos and their larvae.. Mosquitos are estimated to have existed for 100 million years and they have co-evolved with many species, like the mosquito fish. For these species, feeding behaviours that are deeply imprinted genetically may be difficult or impossible to change [2]. Additionally, mosquitos fulfill roles apart from their spot in the food chain. For example, Mosquitos also act as pollinators for many types of plants and impact the migratory habits of caribou which walk through windy areas to escape the swarms, these migration routes in turn shape much of the arctic ecology [2]

So this might impact a few species, but overall wouldn't things be about the same? One classic ecology study showed that the plant more species there are, the larger the total biomass a system can support thanks to“niche complementarity”, ie each plant specialised in a slightly different aspect, making the system much, much more efficient as a whole[3]. It’s hard to say if this would apply to bugs to the same degree, but it does show that ecosystems really do benefit from increased variety of species. So even if one species were to eventually replace mosquitos and most species were able to adapt, the global ecosystem likely would not be quite as full and rich. 

If the world were doing really well, I still might consider getting rid of mosquitos to stop diseases like Malaria, West Nile and Zika. However, during my research I discovered that the world of bugs isn’t so peachy. 66% of of invertebrate species have experienced population declines of 45% during the last 40 years [4]. Similarly, among vertebrate animals overall abundance is declining. Some articles liken mankind to another cataclysmic meteor impact, causing the earths “sixth mass extinction”. A review study in Nature ventured that cumulatively “the effects of biodiversity losses on ecosystem functions is comparable in scale with that of other global changes (such as pollution and nutrient deposition)”, and this loss threatens earths basic ecological functions and is contributing to push us toward global“tipping points” from which we may not be able to return[4]

There’s really no way to accurately predict the impact of killing all mosquitos. There are species effectively disappearing now and we’re struggling to understand the impact due to so many things happening at once. Personally, I wouldn’t risk it. I’d venture a guess that losing mosquitoes would cause a larger ecological “hiccup” than if Earth lost humans.

earth.jpeg

It’s no great surprise that things haven’t been going great ecologically for the past 45 years, but more than ever people are getting informed and taking action to address the many facets of the complicated environmental issues we face. For my next post, I want to look at some of the excellent conservation work currently being done for bugs around the world. 

Thanks for reading! 

Please feel free to comment if something seems amiss, I'm not an expert, but I'll look into it!

Until next time, stay groovy ;) 
~~\0/~~ Janusz

[1] https://www.theguardian.com/environment/2013/may/21/insects-cockroach-bed-bugs-environment

[2] “A WORLD WITHOUT MOSQUITOES” Janet Fang, Nature Vol 466, July 2010

[3] “ Diversity and Productivity in a Long-Term Grassland Experiment”, David Tilman, Science Vol.294, 2000

[4] “Defaunation in the Anthropocene” R. Diazo et.al, Science Vol. 345, July 2014

Bee Kind

This Term's Writer: Alexander Janusz

This Term's Writer: Alexander Janusz