In China the government decided that sparrows were eating too much grain, and killed millions. Then the insects that the sparrows had been eating ate the grain. People starved to death.The government operates on the "Peter Principle" and ends up with incompetent people making bad decisions.
Starlings have been a problem for decades, probably even a century. I don't know what prompted the decision to start poisoniing them but suspect it had something to do with amoount of harvested grain they were eating in the Dakotas.
https://www.historydefined.net/how-killing-sparrows-led-to-one-of-the-greatest-famines-in-history/