A recent study by the Bombay Natural History Society (BNHS) reveals that migratory birds, including flamingos, maintain an altitude below commercial aircraft flight paths while traveling between the Thane Creek Bird Sanctuary and the Navi Mumbai wetlands.
The Adani group-owned NMIAL presented its concerns regarding some of the bird sites NRI colony, Training Ship Chanakya (TCS) and Delhi Public School (DPS) being located close to the airport, as they come within Inner Horizontal Surfaces (IHS) of NMIA.
But with the BNHS allaying these concerns, environmentalists heaved a sigh of relief that the Navi Mumbai wetlands will be saved. The BNHS report forms part of the Half Yearly Compliance Report of Environmental & CRZ Clearance For the ongoing project for the establishment of Greenfield Airport Navi Mumbai International Airport (NMIA).
The flight pattern of birds in Thane Creek, potentially including their path intersecting with the approach path of NMIA runways 08L & 08R (for westerly takeoffs/landings) has been subject to study by BNHS. Based on preliminary data visualisation, the report said that aircraft taking off or landing on NMIA runways typically maintain an altitude above the observed flight elevation of birds in Thane Creek. This is also the case for Runway 09-27 of the existing Mumbai airport, as its eastern approach passes near Thane Creek Flamingo Sanctuary, it said.
When contacted a BNHS spokesperson said this is a preliminary study. “We will have to study further at the actual take-off angle and height to compare the bird and aircraft fight paths,” he said. Environment watchdog NatConnect Foundation, which along with fellow green lovers has been running a series of campaigns to save the wetlands, said with these findings the government must now take urgent measures to save the wetlands.
The compliance report has also committed that CIDCO/ NMIA shall implement the BNHS recommendations for the conservation of the biodiversity around the airport site, NatConnect director B N Kumar pointed out. He pointed out that Navi Mumbai Municipal Corporation (NMMC) has already asked CIDCO to handover the three wetlands to the civic body to be maintained and conserved. But CIDCO is yet to respond, the latest information obtained by NatConnect under the RTI Act shows.
BNHS pilot covered eleven sites based on their locations, habitat, bird species diversity and abundance of which eight were wetlands – Training Ship Chanakya (TSC), Non-residential Indian (NRI) Complex, Delhi Public School (DPS), Kharghar Creek, Kalundre River, Sonari-Belpada, Dastan Phata Jasai, Uran and three were forested areas i.e., Karnala Bird Sanctuary, Chinar, and Mosare.
The study indicated the local movement of birds is driven by tide height and water depth in high-tide roosting sites (inland wetlands) which highlighted the importance of these wetlands in the conservation and management of the birds in these areas.
“This was exactly why we fought for restoring tidal water flow to DPS Flamingo Lake in particular where about 10 pink birds died after the waterbody was rendered dry,” activist Rekha Sankla said. CIDCO had blocked the water flow while constructing the road to Neul Jetty.
BNHS report says it also conducted ringing studies around Mumbai to investigate the migratory ecology of shorebirds. Mumbai has been identified as one of the important areas in the Central Asian Flyways, which plays a vital role in maintaining the fragile group of wader population wintering in India.