On a hazy day in June 2023, doctoral students Trifosa Simamora and Timothy Boycott noticed that the birds at their field site had gone quiet. Now in a study published in Biological Conservation, they show that the culprit was smoke from that summer's record-breaking Canadian wildfires. The smoke dampened the songs and vocalizations of multiple species, with a particularly negative effect on already imperiled grassland birds and birds with ranges specific to the eastern U.S. The reduced communication came at an important time in the birds' breeding cycle, when vocalizations attract mates and establish territories.