The variety of birds on the metropolis’s Sewri mudflats witnessed a big decline between October 2019 and February 2020, in comparison with the corresponding interval final yr, in response to a report by the Bombay Pure Historical past Society (BNHS).
The realm is witnessing building of the Mumbai Trans-Harbour Hyperlink (MTHL) – a 21.8-km bridge connecting Sewri in Mumbai to Nhava-Sheva in Uran – since April 2018. Whereas researchers mentioned it might have saved birds away from the positioning, the report doesn’t conclude so, stating “the impression of the development on birds, whether or not short-term or everlasting, could be inferred solely after 5 years of post-construction monitoring.”
The report, ‘Monitoring and Mitigating impacts of the MTHL on flamingos and different avifauna’, was submitted to the Mangrove Basis of Maharashtra final week. BNHS mentioned the fluctuations had been attributed to a number of components that affect migration equivalent to breeding success, climate, and habitat degradation alongside the flyway in addition to alternate foraging and roosting habitats. The analysis started underneath its 10-year hen monitoring programme throughout choose wetlands in October 2018. Deepak Apte, principal investigator of the undertaking and director, BNHS, mentioned, “The current report is only an annual replace and doesn’t mirror conclusive findings but.”
Flamingo numbers on the 500-hectare Sewri mudflat had been 13,813 in January 2019 and 60,733 in March 2019, which fell to 4,395 in January 2020 and 4,106 in March 2020. This yr’s knowledge included solely 287 higher flamingos throughout March and none in January. It was 1,497 in March 2019. Equally, for all different water birds at Sewri, the quantity dropped from a most of 17,331 birds throughout November 2018 and 15,365 in February 2019 to 1,053 in November 2019 and eight,305 throughout February 2020. Nhava-Sheva, on the opposite finish of the jap seafront, noticed a most of 4,500 water birds and 1,500 flamingos throughout February and March this yr. Information from final yr was accessible solely from Might 2019 onwards when 986 birds had been recorded.
“In contrast to different wetlands within the Mumbai Metropolitan Area (MMR), outcomes confirmed that Sewri and Nhava-Sheva supported decrease species richness and abundance of migratory and resident birds all through the survey interval,” learn the report.
With motion of individuals and equipment, there will probably be disturbance as a result of noise until building takes place, mentioned Apte, including, “These annual updates are serving to us develop a conservation and systematic blueprint for the seascape.”
BNHS additionally printed outcomes of hen behavioural research for 10 species throughout roosting, feeding and building websites in MMR from October 2019 to March 2020. A decline in wader (migratory shorebirds like little stint, Black-tailed Godwit, curlew sandpiper, and customary greenshank) numbers was noticed at Sewri and Nhava-Sheva mudflats, whereas there have been minimal or no observations of Pied avocet and Whimbrels. Birds most noticed had been lesser flamingos, frequent redshanks and lesser sand plovers.
“Through the early migratory season, birds desire the northern a part of the Thane Creek, and later transfer south in the direction of Vashi and Sewri, which is why birds had been seen throughout February and March in Sewri final season,” mentioned Rahul Khot, assistant director, BNHS.
In accordance with mangrove cell researchers, post-monsoon rain and impression of Arabian Sea tropical cyclones throughout October-November 2019 disturbed the pure migratory sample to MMR wetlands. “The numbers drastically elevated from final week of March until the rains started. For Sewri, some hostile results of building can’t be dominated out, however discount in numbers can’t simply be related to that,” mentioned Virendra Tiwari, extra principal chief conservator of forest (mangrove cell).
Mumbai Metropolitan Area Improvement Authority (MMRDA) joint metropolitan commissioner BG Pawar mentioned, “Efforts had been taken to make sure hen inhabitants was not disturbed proper from day one of many undertaking. We have now been further cautious. We have now not seen the report, however will seek the advice of our engineers about it.” MMRDA commissioner RA Rajeev refused to touch upon the matter.