I recall hearing when I was younger that mosquitoes were an outlier in the natural world. With most species, the balance of any food web would be pretty thoroughly disrupted by a major culling. As I heard it, this isn't the case for mosquitoes - if you could press a button and kill them all tomorrow, most ecosystems would be largely unimpacted.
I believe I recall reading that if we were to eliminate only the disease carry mosquitoes, those responsible for transmitting maleria, dengue fever, Ross river virus) there ought not be a problem in the ecological web of life as other mosquitoes would fill the void.
They don't feed on people, or they don't feed in general? If the latter, how do they even survive? They eat in their larval form but then not as adults?
Typically, both male and female mosquitoes feed on nectar and plant juices, but in many species the mouthparts of the females are adapted for piercing the skin of animal hosts and sucking their blood as ectoparasites. In many species, the female needs to obtain nutrients from a blood meal before it can produce eggs, whereas in many other species, it can produce more eggs after a blood meal. A mosquito has a variety of ways of finding its prey, including chemical, visual, and heat sensors.[36] Both plant materials and blood are useful sources of energy in the form of sugars, and blood also supplies more concentrated nutrients, such as lipids, but the most important function of blood meals is to obtain proteins as materials for egg production.[1]
I did a bit of research a while back, and it seemed to agree. Mosquitoes don't keep any other species in check (since their victims rarely die), and they aren't a primary food source for anything; bats will snap them up all night long, but they're still a minority of the stomach contents because they're so small. They are pollinators--I hadn't known that--but, again, they're not primary pollinators for anything, not like bees.
I don't recall reading anything specific about the larvae's importance in aquatic biomes, though, so the anti-mosquitocide guy may have a point.
Maybe they keep bats too busy to eat a more nutritious prey animal, and keep the population from expanding though malnourishment? Similar to the diet of a panda bear, though they unfortunately have no higher-caloric alternative.
I've heard that certain places have remained naturally pristine because mosquitoes have prevented humans from establishing there. I think there is something to this line of thinking.
While unlikely a factor in this case, I wouldn't be so quick to trust National Geographic as it is a for-profit company owned by 21st Century Fox (of Fox News fame). Its credibility shouldn't be categorized on equal footing as Nature.
Am I just making this up/misremembering it?
Edit: found a few sources.
Pro-mosquitocide:
http://www.nature.com/news/2010/100721/full/466432a.html
http://news.nationalgeographic.com/2016/02/160207-mosquitoes...
Anti-mosquitocide:
http://io9.gizmodo.com/what-if-every-mosquito-on-earth-went-...