How Pollution Attracts Flamingos to Mumbai

Flamingos of Mumbai from Thane creek - Photo by AneeshKotwal

If you live in the United States, then your nearest bet for witnessing a flamingo in the flesh - excluding the zoo - is in Florida and the islands and coastal regions around the Caribbean. But if you are stationed beyond American borders or are otherwise elsewhere in the world, then your answer is different. Perhaps the best spot in the world to see flamingos outside of captivity is Mumbai.

You might not associate flamingos with India, but the two are deeply intertwined. Thousands and thousands of flamingos roam the country, particularly in the winter during migration season. Those already in India go further south within the country for that time of year, too.

In Mumbai, these numbers have been blowing up in the last decade. At least 10,000 flamingos descended on the city’s waters in the winter months of 2007. In 2022, that amount escalated to about 130,000. 

Mumbai city water - Free photo by UmashankarRao on Canva.com

Greater and lesser flamingos are the species of the bird that have made India home, and they both appear annually in Mumbai. The city draws flamingos from Pakistan, Afghanistan, more northern regions of India, and from as far as the Middle East and Africa. This is thanks to its rich droves of molluscs, crustaceans, and blue-green algae.

Lesser flamingos are especially fond of the Mumbai environment. Most of the Indian lesser flamingos spend their time in the mudflats of the metropolis. Greater flamingos are better spread throughout India, but Mumbai still attracts masses of them in the winter.

Weirdly enough, Mumbai’s giant human population boom and ensuing pollution increase has helped flamingos. Untreated sewage is a boon for algae growth, and that means food for flamingos.

“Humans impact results in conditions that seem terrible for nature at a glance, but are actually a gold mine for some species,” Sunjoy Monga, a long-time naturalist and Bombay Natural History Society (BNHS) member who led a study on Mumbai wildlife, told Vaishnavi Chandrashekhar of Hakai Magazine in 2022.

Mumbai’s population tripled from 1950 to 1980. In 1979, Navi Mumbai was founded, and greater Mumbai becoming the behemoth it is today was fully set in motion. In 1980, the city had 9.2 million people. Now in 2024, it’s at almost 21.7 million.

Flamingos have followed the humans to the western Indian coastal city, flocking to Thane Creek, the large body of water that separates Mumbai and its sister city Navi Mumbai. Thane Creek has accepted a mass amount of sewage runoff, dumping, and other pollution in the last few decades as humans have taken to the area - a 2016 study declared Thane Creek’s water to be a serious threat to marine life and causing rashes to humans upon exposure.

“The pH value of water has to be between 5-5.9 milligrams per liter, else it can turn the water acidic or alkaline, both of which are not recommended,” a civic official who was quoted anonymously by Manoj Badgeri of The Times of India said in 2016. “Also, the dissolved oxygen levels reveal that the content of the essential gas in the water is grossly inadequate at certain places. This could harm the biodiversity of water bodies here.”

This has hurt animals living and relying on the waters between Mumbai and Navi Mumbai, humans included. But flamingos have flourished.

“It’s a well-studied phenomenon in nature that one species’ waste is food for the other,” Debi Goenka, honorary secretary of the BNHS, told Payal Mohta of The Guardian in 2019. “The sewage in the creek promotes biological growth of blue-green algae, which is food for the flamingo.”

This has created “what one might call perfect levels of pollution” for flamingos, according to Monga, but it isn’t expected to last forever. As the pollution gets worse and the water becomes more contaminated, experts believe flamingos will join most other life that is repelled, not compelled, by the conditions.

“The dumping of sewage and construction debris in the creek is causing the expansion of the mudflats and surrounding mangroves,” Goenka said to Mohta. “At the moment, it’s a great situation for the birds, but this continued expansion will cause the creek to dry up. Then, there won’t be any mangroves or mudflats, and definitely no flamingos.”

That was five years ago. Flamingos are still coming to Mumbai in massive amounts, and Thane Creek is still very polluted. It might not be so in a decade-plus, but for now, Mumbai from October through March remains one of the best places to see wild flamingos in the world.