I'd lay odds it will just be the usual cause - habitat loss. These insects evolved to inhabit in wild environment. Now we moved most of it over to monoculture.
Back when I was young locust plagues were a thing. They wiped out vast areas crop land. We they came near the cities the eat the washing on the line.
I noticed they were dropping off. Now I haven't heard about a locust plague anywhere in at least a decade. Which was odd, because when they were happening we spent huge amounts of money trying to control them. Planes would fly through the things dispensing insecticide, but it wasn't terribly effective because the insect bodies with pile up inside the engines causing them to over heat. In fact nothing we did seem to have much effect.
What wiped them out was changes in land use. Part of their life cycle was burring their eggs just below the surface on fertile grass land. Planting crops wasn't a killer issue for them - but ploughing was. Eventually we converted all those locust breeding grounds to crop land, and once we did that they were gone.
They are gone forever now - extinct. If you read the article you can see we were triumphant over eliminating a major pest for a while. Now, not so much.
There is actually a good documented example. https://academic.oup.com/bioscience/article/55/1/80/248302
Back when I was young locust plagues were a thing. They wiped out vast areas crop land. We they came near the cities the eat the washing on the line.
I noticed they were dropping off. Now I haven't heard about a locust plague anywhere in at least a decade. Which was odd, because when they were happening we spent huge amounts of money trying to control them. Planes would fly through the things dispensing insecticide, but it wasn't terribly effective because the insect bodies with pile up inside the engines causing them to over heat. In fact nothing we did seem to have much effect.
What wiped them out was changes in land use. Part of their life cycle was burring their eggs just below the surface on fertile grass land. Planting crops wasn't a killer issue for them - but ploughing was. Eventually we converted all those locust breeding grounds to crop land, and once we did that they were gone.
They are gone forever now - extinct. If you read the article you can see we were triumphant over eliminating a major pest for a while. Now, not so much.