Populations of many pollinators, including bumblebees, have been crashing over the last few decades, thanks to the widespread use of chemical pesticides, loss of habitat and the acceleration of climate change. But it can be hard to know just how bad the problem is, or whether conservation strategies are helping, without relying on lethal traps—which can kill tens of thousands of bees in order to get an accurate count of their populations. ...read more read less