Peter Chatanga uses weeks-long audio recordings to build a picture of biodiversity in Lesotho’s crucial wetlands

I listen to the sounds this remote wetland makes to learn its rhythms

I am an ecologist from Zimbabwe, but I’ve been based at the National University of Lesotho in Maseru for more than 13 years. In the picture, I am standing in a stream that runs through the Bokong Nature Reserve, part of Lesotho’s first UNESCO biosphere reserve, designated in 2021.

Lesotho is a mountainous, landlocked kingdom in southern Africa. Its high-altitude wetlands supply the Lesotho Highlands Water Project, which delivers water to the Vaal River System in South Africa, generating both income and hydroelectric power for Lesotho. The electricity lines in the background of this photo are part of that.

I study the delicate ecological balance that keeps these areas functioning properly: the wetlands trap water when it rains and release it gradually during dry periods. An important part of this is to map the vegetation, animals and general environmental conditions, and how they change over time.

One of our projects monitors the soundscapes of these areas to identify the animals that live here. We leave our sensitive recording equipment in the field for weeks at a time. This is especially helpful because, although this site is just 180 kilometres from my university in the capital of Lesotho, it can take up to four hours to drive here.

The data sets we gather are huge, and although we do listen to the recordings, we mainly use software to help us analyse the data. We want to compare our recordings between seasons, between dawn and dusk and between day and night, to understand the rhythms of the ecosystem. We also compare our recordings from different wetland types. High-altitude areas are susceptible to climate change and, in my view, it is the greatest threat these protected wetlands face.

Listening to the recordings makes me happy because I enjoy hearing a variety of sounds, especially the singing of different birds. In a small country such as Lesotho, there are so many knowledge gaps to fill — it’s one of the benefits of being a researcher here.

Nature 626, 684 (2024)

doi: https://doi.org/10.1038/d41586-024-00395-z

This story originally appeared on: Nature - Author:Linda Nordling