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Comment by j_s | Hacker News Reader

I believe the primary source was discussed last week. (Discussion is still open but ain't nobody got time for that once it's off the front page!)

75% decline over 27 years in total flying insect biomass in protected areas | https://news.ycombinator.com/item?id=15502074 (Oct 2017, 428 comments)

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Last week's article motivated me to plant Milkweed (Asclepias tuberosa and Asclepias incarnata) in my garden next year, to help with the population of Monarch butterflies and bees.

On the other hand, I'll still be deploying my organic mosquito control based on plant oils injected into a mister system. I really don't think mosquitoes fulfill any role in the ecosystem that can't be filled in by other species; but the difficulty is in avoiding messing with any other insects.

I really don't think mosquitoes fulfill any role in the ecosystem that can't be filled in by other species

This is literally the exact kind of hubris that got us in this mess in the first place...

Mosquitos pollenate plants. And they're an important food item for migrating bugs and birds. Less than 40% of them feed on blood, nor is it their only diet among those that do.

It's interesting how matter of factly you spread such a casual opinion about what our ecosystem does and doesn't need.

> I really don't think mosquitoes fulfill any role in the ecosystem that can't be filled in by other species

They are so ubiquitous and numerous that they are without a doubt an important part of the food chain. Removing them from the equation will seriously disrupt the eco-systems they are a part of, and dramatic changes will happen. I cannot tell you what, because no one knows - but they are an important source of food the animals higher up the food chain. Maybe we get overcrowded by flies and spiders. Maybe most birds disappear. Maybe bees die out because mosquitoes kept a parasite at bay, leading to significant change in vegetative matter.

Most of our world is very adaptable, but it is also highly tuned, finely balanced, and complexly interconnected.

This article gives even more supporting evidence, citing declines in butterflies and honeybees from other sources.

Pretty sure these were pulled as highlights from the "References" section, but I can't guarantee that beyond confirming they are listed there. The article does add some interpretive commentary quoting experts.

The best TL;DR I could grab from the previous discussion:

>MrBuddyCasino https://news.ycombinator.com/item?id=15503474

Der Spiegel discusses issues in the methodology of the data collection. The intervals over the years weren't uniform, data was collected by volunteers/hobbyists and they did not measure the dry mass weight. There are differing opinions whether or not those issues have relevance.

SZ gives some details on suspected causes. Neither climate change (warmer weather should yield more insects, not less) nor changes in plant diversity can explain the observed effects alone. Main suspects:

- agricultural fertilizers, especially nitrogen

- pesticides, especially neonicotinoides

> 75% decline over 27 years in total flying insect biomass in protected areas

The measurements took place in protected areas in Germany. Have there been similar studies for other locations?

Edit: It appears that almost all the measurements took place at locations in Nordrhein-Westfalen, Germany's most populous state ...

> S1 Fig. Map of study area.

> Insect trap locations (yellow points) in Nordrhein-Westfalen (n = 57), Rheinland-Pfalz (n = 1) and Brandenburg (n = 5)

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