Thane creek wetlands need to be saved

The wetland and the adjacent Thane Creek Flamingo Sanctuary are globally significant, serving as a stop for migratory birds
The number of flamingos decreases at Thane creek due to illegal dumping.(HT Photo)
The number of flamingos decreases at Thane creek due to illegal dumping.(HT Photo)
Updated on Jun 02, 2019 11:42 PM IST
Copy Link
Hindustan Times | By, Mumbai

Last week, this newspaper reported a study that warned about the shrinking wetlands along Thane creek.

The study by Bombay Natural History Society (BNHS), which looked at wetlands around the Bhandup sewage pumping station (BPS), said that sedimentation and encroachments have shrunk its area from 3.5 square km in 1973 to just over one square km in 2018.

Thane creek, located between Mumbai harbour — with two shipping hubs, the Mumbai Port and the Jawaharlal Nehru Port on its south the Ulhas River on its north — is 26 kms long and its narrower upper areas have mudflats, salt pans and diversity-rich mangrove forests. Studies by groups like Salim Ali Centre for Ornithology and Natural History and BN Bandodkar College of Science Thane and Bombay Natural History Society have found that the creek is home to more than 160 bird species and nine species of mangrove trees, besides fish, crustaceans and insects.

These species and phytoplankton, single-celled plants that form the basic life-building block in aquatic systems, providing food for shrimp, snails and fish, are important for sustaining the local fishing industry.

The wetland and the adjacent Thane Creek Flamingo Sanctuary are globally significant, serving as a stop for migratory birds using the Central Asian Flyway which stretches across Asia, Europe and the Arctic and Indian Oceans. There are four near-threatened bird species and 14 migratory ones in the area, which fall under schedule I of the Wildlife Protection Act, 1972, giving these birds a high grade of protective status.

Significantly, it is the second-largest natural area in Mumbai, next to the Sanjay Gandhi National Park (SGNP), spread over 59 square km, according to the Forest Survey of India.

In May 2018, the Maharashtra government had announced the creation of the Thane Creek Flamingo Sanctuary on 1,690.5 hectare (1.6 sq km). Additionally, the state government recently has proposed to create a 34 sq km buffer zone around the sanctuary.

Despite its status as a protected sanctuary, the creek is threatened by pollution and encroachments. Research by Ryerson University, Toronto had reported that a third of the mangrove forests in the Mumbai Metropolitan Area has been lost to urbanisation since the 1970s.

A study by the civil engineering department of the Indian Institute of Technology – Bombay (IIT-B), meant to understand the siltation problem in the two ports, said that around one metre of silt is deposited annually in the harbour basin, forcing the port companies to spend money on dredging the navigational channel to keep it deep enough for ships.

Another study, by BN Bandodkar College of Science, Thane, said the creek’s biodiversity has declined over the decades because of industrialisation and expansion of urban areas on its banks. The study found low dissolved oxygen, high nutrients from run off and siltation. The high nutrients can lead to excessive growth of phytoplankton that can choke other life.

The BNHS study said construction around the creek has changed its natural state dramatically. Constructed area in the wetlands has increased from 132 hectare to 787 hectare since the 1970s. This has resulted in a 70% drop in the wetland area (mudflats) — from 344 hectare in 1973 to 100.3 hectare in 2018.

Sedimentation has narrowed the creek and reduced its water area, but mangrove cover has increased by 53%, from 652 hectare in 1973 to 999 hectare in 2018. While this is good as the expansion of mangroves has increased the creek’s cover, most of the new mangrove growth is from one species that can thrive in poor water quality. This means a decline in diversity.

But the creek can be restored to health. Studies have said that lower stretches of the creek, where it is wider and flushed by tides, still support relatively higher diversity because pollution gets diluted. This section has mangroves and birds, including the creek’s most well-known visitors, flamingos. Desilting, treatment of sewage before it is released into the creek, mangrove plantations and conservation projects that partner with the local fishing community can revive the ecosystem.


    Manoj R Nair is part of Hindustan Times’ nationwide network of correspondents that brings news, analysis and information to its readers.

Close Story

Less time to read?

Try Quickreads

  • Gogi was shot dead by members of Tillu Tajpuriya gang inside Rohini district court in September last year. (HT File)

    2 Gogi gang members nabbed, 2 guns seized

    Deputy commissioner of police (outer north) Brijendra Kumar Yadav said that both the detained “sharpshooters” are minors. Yadav said, during questioning the two juvenile delinquents told the police that they were asked to avenge the killing of one Brahm Prakash, father of Kallu Khera alias Kapil who is a member of the Gogi gang. They said Prakash was killed on May 7 allegedly by members of Bawana’s gang, and senior members of their group told them to kill latter’s father.

  • Protesters raise slogans demanding the release of Yasin Malik during a protest outside separatist leader in Srinagar’s Maisuma on Wednesday. (Waseem Andrabi Hindustan Times)

    Protests erupt in Srinagar’s Maisuma

    Clashes erupted between supporters of Yasin Malik and security forces in Srinagar on Wednesday after a Delhi court sentenced the Kashmiri separatist leader to life imprisonment in a 2017 terror funding case. Protests against the court's verdict erupted in Maisuma – Malik's native place, a short distance from Lal Chowk – as his supporters and relatives arrived at his house and shouted slogans demanding his release.

  • In the new team, the Shimla district, particularly Rohru and Jubbal and Kotkhai assembly segments, has got more share than the other 66 assembly segments. (Image for representational purpose)

    Himachal: Pratibha, Vikramaditya get bigger roles in PCC expansion

    In the new team, the Shimla district, particularly Rohru and Jubbal and Kotkhai assembly segments, has got more share than the other 66 assembly segments. Of the 41 newly appointed secretaries, seven are from the Rohru assembly segment and they all owe allegiance to Mandi Lok Sabha member Pratibha Singh and her legislator son Vikramaditya Singh, while of the 13 general secretaries, five are from Shimla district alone. Former councillor Mahender Chauhan has also been appointed as vice-president.

  • The Delhi high court said it will hear further arguments on the bail plea of Umar Khalid on May 30. (PTI Photo/Shashank Parade)

    Can’t hold mini trial during bail plea: HC to Umar Khalid

    A bench of justices Siddharth Mridul and Rajnish Bhatnagar on Wednesday said that it will not hold a “mini-trial”, and look into the evidence and the statements without testing the authenticity of the material. “In so far as UAPA is concerned, we have to look at the material on the record without testing the veracity... You can’t say if the statement says three of them (accused) met, then we should test it by holding a mini-trial,” the bench said.

  • After achieving the first position in administering first and second doses of Covid vaccine in Himachal, the tribal districts of Kinnaur and Lahaul-Spiti have again taken a lead in giving the booster dose to the eligible population in the state even as all other districts lag way behind. (Image for representational purpose)

    Himachal’s tribal districts take lead in booster dose vaccination

    In the other tribal district of Lahaul-Spiti, 64% eligible population has been administered the precautionary dose . Chamba has achieved 34% coverage and Kullu around 37%. In Himachal, more than 8 lakh people were eligible for the booster shot as on May 24. Since the launch of the booster dose drive in January, 3, 15,734 precautionary doses have been administered in the state which is 40% of eligible population.

Story Saved
Saved Articles
My Reads
Sign out
New Delhi 0C
Thursday, May 26, 2022