“Scientists have been hard at work cracking the “mystery” of colony collapse disorder. [“Studies link pesticides to decline of bee colonies,” News, March 30.]

A new study released yesterday, and two published last week, strengthen the case that neonicotinoid pesticides are key drivers behind declining bee populations — alone and especially in combination with other stressors. This class of pesticides covers 143 million acres of U.S. countryside, and more damning studies are awaiting publication.

Yet, pesticide corporations like Bayer and others are running a predictable PR defense aimed at delaying action by manufacturing doubt — it’s called the “tobacco strategy.”