I just can across this article, which pretty much spends the entire article explaining how Monsanto (producers of the weed killer RoundUP) are the cause of the disappearance of Monarch Butterflies.
But I just can't agree. There's an announcement that the article refers to, which says that "habitat loss, pesticide overuse and climate change" are contributing factors to a decline in Monarch populations. Interpreting that as being a single product created by Monsanto (RoundUP is a Monsanto name, other companies just call it glyphosate) is drawing a conclusion that has little to no supporting evidence, in my opinion, though it's surely part of the problem.
RoundUP isn't killing the monarchs: it's one of many factors that is eliminating their food supply. And that's what products like RoundUP, which are made to kill weeds, are supposed to do. I don't have a solution here, but I don't think it's fair to directly blame Monsanto or other companies for this problem. These herbicides are preventing the weed from regrowing on land that we are currently using. It is not Monsanto's fault because all the chemical is doing is preventing the weed from growing on land that we already cleared for growing crops.
Think about it, though: when was the last time you saw a real plump, red native ladybug and not one of those invasive red/orange/yellow ones? It's not just the butterflies: it's happening all over to all sorts of insects.
When, and how, can we see the return of butterflies? Well, I'm not too sure. But we can start by planting milkweed native to our areas, and allowing it to grow: and then, go from there!