Mumbai, India - It is a thorny issue that beleaguers this fast diminishing community daily - how to preserve a 3,000-year-old ritual of giving "sky burials" to the Parsi dead amid a nearly extinct vulture population?

In 1931, in the wildernesses of the Malabar hills overlooking the financial capital of Mumbai, Parsi Zoroastrians erected a Dakhma - Tower of Silence. Fleets of white-rumped and long-billed vultures once swooped and returned to the blue skies after having quickly devoured the corpses left there.

"Sadly, the scene is entirely different today," Khojeste P Mistree, head of the community association for the Bombay Parsi Punchayet in Mumbai, told Al Jazeera.

"Ravens and kites have replaced vultures. The bodies take time to excarnate."

A fading ritual

Of the total 138,000 Zoroastrians left in the world, around 69,000 live in India. Mumbai alone has some 40,000 Parsis who live in homes tucked away in affluent neighbourhoods.

Seeking freedom of religion and economic rights, their ancestors had left Iran in the early 10th century for India's western coastal area called Sanjan - some 185km north of Mumbai.

As the community flourished, they came to be known as Parsis (the Persians). With them came the tradition of the structures erected in the woods so as to expose their dead to scavenging birds, mainly vultures.

The Parsis consider land and water to be sacred and they must not be "polluted" with a dead body. In the process of excarnation, a bare corpse was positioned on the walls of one of three circular wells - one for children, one for men, one for women - awaiting scavenger birds.

When there was no more flesh left on the body, the skeleton tumbled inside the deep well connected to a further four external wells through channels. Layers of charcoal and sand fitted inside each well filter the remains before they fell and mixed with the soil.

Lethal drug

With the vultures gone, this ritual is on the brink of extinction too.

"The vultures disappeared nearly 30-35 years ago from the Tower of Silence," Asad Rahmani, Director of the Bombay Natural History Society (BNHS) told Al Jazeera.

"At that time, it was presumed that they disappeared due to change in the land use, and construction of tall buildings all around. But I think vultures declined mainly due to the prevalence of Diclofenac - a pain killer that had just come into use for humans."

The massive decline in the vulture population across Mumbai and the entire Maharashtra state began from 1992-93 onwards when the Indian government opened this drug for use in livestock as well. Today, there is not a single vulture in the state, according to Rahmani.

"Diclofenac is lethal to vultures. It does not matter from where they get it, from a dead Parsi or from a dead cow," Rahmani said.

As corpses take longer, sometimes eight weeks, to decompose fully, the tower of silence continues to be a scene of partially decomposed bodies. Photography in the area is discouraged and non-Parsis are prohibited from entering the excarnation site.

Solar power

This has pushed some of the Parsi elders to blend the ritual of "sky burials" with modern technology.

"For 800 deaths a year, we need at least 250 vultures. But since there are no vultures around, we've installed solar concentrators. I think that's the only way out now," Dinshaw Rusi Mehta, a member the Bombay Parsi Punchayet, told Al Jazeera.

The solar panels converge light and heat at 110 degrees Celsius on a corpse to quicken decomposition.

Mehta, however, pointed out that the solar panels are "useless" when the sun sets and during monsoon season.

The community remains divided over whether to increase the number of solar panels or continue the ritual of "sky burials" when ravens and kites are the only scavengers flying over the site.

Disagreements within the Punchayet have also stalled a government project that would have seen aviaries being set up to breed vultures. The plan had envisaged the vultures again flying over the Parsi towers by 2014.

Under this project, the BNHS was meant to replicate its vulture upkeep plan - a success story in five India states - in Mumbai, with the Parsi community's help, but Rahmani says: "We had discussed this project with Parsis but nothing came out of our discussion."

Waning community

Together with the decline of the vultures, the Parsis are facing their own decline.

Their number has remained almost static at 69,601 since 2001, as compared with a 21 percent general population growth in India.

The community elders cite several reasons for this. They say the young are not getting married, or are marrying late; there is a decline in fertility, an exodus of the educated young to the US or the EU, and marriages outside the community.

On average, Parsi women have less than one child (0.8) during their lifetime, while one in every four is a mixed marriage.

A legend describing a treaty the Parsi community signed with then Hindu rulers when they reached the eastern shores of the warm Arabian Sea in the 10th century, says that one can be a Parsi only by blood.

"We kept our word we gave to then king Jadi Rana," said Dinshaw Rusi Mehta of the Bombay Parsi Punchayet.

"When we were given asylum in India, we agreed not to convert the locals to our faith. This isn't part of our religion though. It's just a pact we've been following for centuries now."

"But today, we have gone beyond the point of no return."

In 2013, the Indian government tried to reverse this trend by launching a "Jiyo Parsi" (Live Parsi) scheme in which $1.5m were reserved to address fertility issues and counselling on early marriages and family planning, but there has been little success so far.

"The highest presence of bachelors and spinsters in any faith of the world are in our community," Mistree of the Punchayet said.

"On average, for every three deaths, there is only a single birth. This ratio is haunting us. In the next 80 years, we fear our identity will be gone. This is something our youngsters should think over."

Currently, over half of the Parsis are over 40. The clergy is ageing and so are the pallbearers. Their children refuse to adopt the family occupations and instead reap the dividends of the massive post-1990 economic growth in India.

Faith on high seas

This concern too has pitted reformists and traditionalists against each other.

For instance, 65-year-old Zarina, who only gave her first name, from the posh Parsi Colony, said her son has a "totally different outlook and style".

"The young men don't want to study beyond a safe zone whereas girls are all well-educated. They prefer to marry boys who equal them in education which is why most of the marriages are mixed," she said.

"I think we should accept reality and adopt children of such marriages into our faith. It's the only way to increase our population."

Though Zarina wants the immediate return of vultures and a "sky burial" when she dies, she said the community should adopt electric cremations "in case the scavengers don't return".

Powerful orthodox Parsis like Mistree, however, insist young men and women should marry within the community and multiply.

He believes "sky burials" are an important part of the Zoroastrian religion and an "egalitarian way" to decompose bodies. Opening the doors of religion to non-Parsis would "disintegrate" the community, he insisted.

"We're a tiny boat on the high seas and it's a unique boat. We shouldn't abandon it in the middle of sea," said Mistree, head of the Bombay Parsi Punchayet.

Today four officials of the seven-member Punchayet say the "sky burial" is the only religious method of decomposing a Parsi body and aviaries should be installed. While others disagree and insist on the introduction of modern technology.

Whether vultures return or not, these differences will remain.

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