Haze from the 2015 forest fires in Southeast Asia may have killed about 100,000 people. It was also really bad for wildlife. Benjamin Lee and colleagues recently showed these effects by measuring acoustic activity on an ‘eco-overpass’ between two areas of forest in Singapore before, during and after the haze event. The data showed that acoustic activity dropped by 37% during the haze, and had showed only partial recovery 16 weeks later.

I learned of this research through the excellent BBC World Service Inside Science Programme on 12 October 2017. What caught my attention was the serendipitous nature of the study. Lee was supposed to be surveying bats to assess the effects of the overpass. But the haze triggered his asthma, and he had to stop work: but his acoustic recorders stayed in place. And hence a dataset was collected that spanned the haze event, recording not just bats but also birds and insects, and showing how they were silenced by the conditions.

This neat paper highlights the extraordinary power of remote devices to record biological data. Digital acoustic recording is widely used to survey bats (e.g. the iBats programme) and increasingly birds and insects. Moreover, archived sound recordings made for one purpose can be mined later for another. Citizen science recordings of bats in the UK have been used to identity stridulating bush-crickets. Continue reading →