Nidhi Johri
Who I am
I grew up in North India, far from the coastline but with a strong fascination for the sea and the creatures that inhabit it. That interest led me to pursue a Master’s degree in marine science, specialising in marine biology, and to continue with a PhD in environmental studies at Ashoka University. My work has taken me to fishing harbours along the Bay of Bengal, where I have spent countless hours documenting sharks and rays as they are landed and traded.
Over the years, I have become particularly focused on rays, animals that are ancient and graceful, and often overlooked. Many of the species I study, like the honeycomb whipray and longtail butterfly ray, are threatened with extinction, yet they continue to be caught and consumed across India. My goal is to connect their conservation with something people care deeply about: their own health. By showing how these rays accumulate toxic metals that can harm those who eat them, I aim to build stronger reasons to protect them.
Where I work
My research is based along the Bay of Bengal coast in West Bengal, India. The project focuses on two busy landing sites, Digha and Fraserganj, where hundreds of fishing boats return each day with their catch. These harbours are full of life and energy as fish are sorted, auctioned and transported to local and regional markets. Rays are among the species landed here, often in large numbers, despite their threatened status.
This coastline, however, is under pressure. Rivers carry pollution from industries and cities upstream, including heavy metals that end up in the sea. Combined with intensive fishing, this makes the Bay of Bengal a place where marine life faces multiple stresses. At the same time, these waters support coastal communities that depend on fishing for their food and income. It is this complex mix of biodiversity, pollution and livelihoods that makes West Bengal such an important place for my research.
What I do
My PhD investigates the trade and consumption of rays and sharks across India and Bangladesh, focusing on both the human and ecological dimensions of this issue. These species play vital ecological roles, but are increasingly threatened by overfishing and trade pressures. Unlike high-value shark fin markets, in South Asia the demand for ray and shark meat remains significant, yet poorly studied.
My work combines field-based socio-economic research with laboratory-based species identification. In practice, this means spending time at fish landing sites, harbours and local markets. As well as documenting landings at these locations, I interview fishers, traders and consumers to understand the movement of ray and shark products. In coastal and inland communities, I conduct household surveys to learn about the motivations and barriers that influence consumption and to explore how factors such as income, culture, religion and taste shape demand.
A typical day in the field usually begins before sunrise at the landing sites, where I record species being landed and collect samples from rays. These samples are later analysed in the laboratory to test for mercury, cadmium, lead and other metals. Alongside this, I speak with local families and fishers to understand how often they consume rays and how these species are used in their communities.
This combination of scientific analysis and community engagement is central to my work. In the lab, the focus is on generating data that can show whether rays are safe to eat. In the community, I concentrate on sharing this knowledge in simple, accessible ways. By explaining both the conservation importance of rays and the risks of consuming contaminated meat, I hope to encourage people to see these animals differently, not as low-value bycatch but as species that need protection for the health of the ocean and of people.