murky waters

Sewage from Mumbai and Karachi is killing fisheries in the Arabian Sea

Sewage and factory waste from cities like Mumbai and Karachi is nurturing a kind plankton that stifles organisms eaten by fish.

Five years ago, a team of scientists from India and the United States began to take research expeditions in the northern waters of the Arabian Sea, checking out a new marine species that was taking over large tracts of water. It was first observed in 2003 that the plankton species, which blooms in the winter months, was becoming thicker and more widespread. It lay like a green blanket on the surface of the water – a blanket that could stifle the normal marine food chain, having direct impact, for one, on the abundance of fish that ends up in the markets of Maharashtra and Goa.

After three years of testing the water, the team has found that the northern regions of the Arabian Sea have been turning hypoxic, or low on oxygen. The new plankton, Noctiluca scintillans, grows particularly well in low-oxygen environments. Once confined to a few zones in the sea and blooming only occasionally, N. scintillans is now a dominant type of plankton that blooms every year and is displacing fish-feeding plankton called diatoms.

N. scintillans cell (~1 mm in diameter), next to an amphipod showing that it is to big to be eaten by a similar sized zooplankton.
Image: SGP Matondkar

Landlocked off to the north, marine life in the Arabian Sea is dependent on the annual monsoon winds, which draw the nutrients they need for sustenance up from the depths of the ocean. Once the monsoons have passed over the sea, there’s a burst of growth of diatoms. In healthy, life-sustaining marine systems, diatoms are eaten by zooplankton, which in turn are eaten by fish – a sequence that has continued in the Arabian Sea for centuries.

Changes in climate, warming landmasses and pollutants from coastal cities are rocking the balance, warn ocean researchers in a paper published in Nature Communications.

“Bottom water brought to the surface has low oxygen, and coupled with waste water from cities and factories, it triggers hypoxia,” said SGP Matondkar of Goa’s National Institute of Oceanography in an email to Scroll. Matondkar worked on this study with biogeochemists from Columbia University and other marine scientists and microbiologists.

As the population in the Metropolitan Mumbai Region has doubled over the last decade to 21 million, the paper contends, the city discharges 2,700 megaliters per day of wastewater into the Arabian Sea. Since wastewater treatment has not kept pace with the growing city and industrialisation in the area, it is severely short of oxygen. In the same manner, the Pakistani city of Karachi, with a population of 15 million people, sends 1,600 megaliters of domestic and industrial wastewater into the sea. This means that 70% of the water is severely oxygen-depleted. The boom in fertiliser use and the corresponding quantities of agricultural run-off emptying into the sea could also be contributing to the oxygen shortage.

Trail of green N. scintillans on the sea surface.
Image: SGP Matondkar

The growth of N. scintillans in oxygen-depleted waters stymies the growth of diatoms. While N. scintillans also ingests diatoms, it is too big to be eaten by zooplankton and instead feed gelatinous animals called salps, and jellyfish. Matondkar has observed jellyfish populations on the rise in some areas, further indication of a shift in the sea’s ability to support fish populations.

Fisheries haven't started reporting any effects of the problematic algae yet because the blooms have not coincided with the commercial fishing season along the Arabian coast. But the danger grows as N. scintillans continues its conquest of the Arabian Sea. “The commercial fishing catch is up to January-end. The bloom initiated during February,” Matondkar said. “Noctiluca blooms appear much after the peak in commercial fishing activity. If the bloom happens early, fisheries will collapse.”

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Changing the conversation around mental health in rural India

Insights that emerged from discussions around mental health at a village this World Mental Health Day.

Questioning is the art of learning. For an illness as debilitating as depression, asking the right questions is an important step in social acceptance and understanding. How do I open-up about my depression to my parents? Can meditation be counted as a treatment for depression? Should heartbreak be considered as a trigger for deep depression? These were some of the questions addressed by a panel consisting of the trustees and the founder of The Live Love Lough Foundation (TLLLF), a platform that seeks to champion the cause of mental health. The panel discussion was a part of an event organised by TLLLF to commemorate World Mental Health Day.

According to a National Mental Health Survey of India 2015-16, conducted by the National Institute of Mental Health and Neurosciences (NIMHANS), common mental disorders including depression, anxiety disorders and substance use disorders affect nearly 10% of the population, with 1 in 20 people in India suffering from depression. The survey reported a huge treatment gap, a problem that is spread far and wide across urban and rural parts of the country.

On 10th of October, trustees of the foundation, Anna Chandy, Dr. Shyam Bhat and Nina Nair, along with its founder, Deepika Padukone, made a visit to a community health project centre in Devangere, Karnataka. The project, started by The Association of People with Disability (APD) in 2010, got a much-needed boost after partnering with TLLLF 2 years ago, helping them reach 819 people suffering from mental illnesses and spreading its program to 6 Taluks, making a difference at a larger scale.


During the visit, the TLLLF team met patients and their families to gain insights into the program’s effectiveness and impact. Basavaraja, a beneficiary of the program, spoke about the issues he faced because of his illness. He shared how people used to call him mad and would threaten to beat him up. Other patients expressed their difficulty in getting access to medical aid for which they had to travel to the next biggest city, Shivmoga which is about 2 hours away from Davangere. A marked difference from when TLLLF joined the project two years ago was the level of openness and awareness present amongst the villagers. Individuals and families were more expressive about their issues and challenges leading to a more evolved and helpful conversation.

The process of de-stigmatizing mental illnesses in a community and providing treatment to those who are suffering requires a strong nexus of partners to make progress in a holistic manner. Initially, getting different stakeholders together was difficult because of the lack of awareness and resources in the field of mental healthcare. But the project found its footing once it established a network of support from NIMHANS doctors who treated the patients at health camps, Primary Healthcare Centre doctors and the ASHA workers. On their visit, the TLLLF team along with APD and the project partners discussed the impact that was made by the program. Were beneficiaries able to access the free psychiatric drugs? Did the program help in reducing the distance patients had to travel to get treatment? During these discussions, the TLLLF team observed that even amongst the partners, there was an increased sense of support and responsiveness towards mental health aid.

The next leg of the visit took the TLLLF team to the village of Bilichodu where they met a support group that included 15 patients and caregivers. Ujjala Padukone, Deepika Padukone’s mother, being a caregiver herself, was also present in the discussion to share her experiences with the group and encouraged others to share their stories and concerns about their family members. While the discussion revolved around the importance of opening up and seeking help, the team brought about a forward-looking attitude within the group by discussing future possibilities in employment and livelihood options available for the patients.

As the TLLLF team honoured World Mental Health day, 2017 by visiting families, engaging with support groups and reviewing the successes and the challenges in rural mental healthcare, they noticed how the conversation, that was once difficult to start, now had characteristics of support, openness and a positive outlook towards the future. To continue this momentum, the organisation charted out the next steps that will further enrich the dialogue surrounding mental health, in both urban and rural areas. The steps include increasing research on mental health, enhancing the role of social media to drive awareness and decrease stigma and expanding their current programs. To know more, see here.

This article was produced by the Scroll marketing team on behalf of The Live Love Laugh Foundation and not by the Scroll editorial team.