Our Summer of Sound and Satellites


Sarika Khanwilkar is a Student Conservation Association alumnus and currently a PhD student in the Ecology, Evolution, and Environmental Biology (E3B) department at Columbia University. She works closely with Pooja Choksi, a fellow PhD student, doing research in central India. They wrote about their latest summer below:

Our Summer of Sound and Satellites

Sarika Khanwilkar and Pooja Choksi

Ask an ecology student how they spent their summer doing fieldwork and you’ll probably get one of the following responses: tracking large mammals, catching snakes (very routine for this field), measuring trees (with and without beehives!) examining mammalian scat (the smelly, runny and dry kinds!) or other equally relatively unusual activity. We spent our summer climbing trees, listening to the sounds of the forest and collecting GPS points to validate satellite images in central India.

It was June in central India, where we met to continue data collection as part of Project Dhvani. We started Project Dhvani with a fellow student, Vijay Ramesh, during our first year as PhD students together. Using acoustic recorders, we record sounds of vocalizing biodiversity to measure the impact of human land use on this biodiversity.

Two different types of acoustic recording units: on the left is a Swift recorder and on the right is an AudioMoth.

The field of acoustics has seen rapid advancement in academic interest and technology. Despite the promise that newer technology holds, unique challenges present themselves when conducting ecological research. Torrential downpours from the monsoon was the biggest challenge we had to overcome by creatively waterproofing our recorders. We also learned that recorders need to be camouflaged and hidden to remain out of the reach of humans or wildlife when deployed. To solve this challenge, we had to go back to our childhoods. To hide our recorders, we tied them high up in a tree which required some good tree climbing skills, which we hadn’t put to use since several years!

Pooja was reminded of her childhood as she placed a recorder high in a tree on the outskirts of Kanha NP.

In addition to Project Dhvani, our lab is making a map of central India through the classification of satellite images. We needed to collect ground validation points to make our map more accurate, which required us to travel to remote places around the landscape and take GPS points of different land cover types.

The Kanha-Pench habitat corridor is forest that connects two national parks in central India, Kanha and Pench, and is critical to allow animal movement between the parks. Tigers are the most charismatic of species that utilize the Kanha-Pench corridor, along with sloth bears, wild dogs, leopards, jackals, and deer species such as chital or sambar. We traveled along a mysterious dirt road that, to our pleasant surprise, was surrounded by unprotected forest which showcased diversity comparable with the protected areas kilometers away. We were happy to see functional habitat within the corridor.

Sarika taking ground validation points for the land cover map.

The dirt road we traveled going through the Kanha-Pench habitat corridor.

Example of where a GPS point for cropland was taken. 

Example of where a GPS point for a teak plantation was taken. Teak is a deciduous tree and had lost its leaves in the late summer.

Example of where a GPS point for trees was taken.

While traveling to places to record sound or validate satellite images, we encountered some special sights. During a trek into Satpura National Park, we found leopard scat on our trail. Thankfully, it was a few days old, but it could come back at any time, and we made sure we were more careful while hiking!

As we hiked through Satpura NP, we crossed the largest termite mound either of us had ever seen.

A male and female Peninsular rock agama found during a trek in Satpura NP.

The worst part of the trip was seeing deforestation. As students, we are sometimes confined to our desk, where we ‘see’ biodiversity loss through satellite imagery and by quantifying changes with other data sources. However, experiencing environmental destruction in real life is unsettling in ways that other scientific methods cannot replicate.

A couple large trees cut down in area outside a Protected Area.

Student Conservation Association