Night herons are back at Yamuna park, experts say it’s a positive sign
In 2016, park authorities spotted around 2,000 nests, which shot up to at least 2,500 in 2017. This year, scientists are expecting around 5,000 nests in the park. Park authorities are now planning to monitor the birds — particularly the black-crowned night herons — around the clock to understand their nesting ecology and feeding habits.Updated: Apr 07, 2019 04:31 IST
The otherwise quiet and tranquil Yamuna Biodiversity Park (YBP) has, of late, become lively with the quok and woc of black-crowned night herons. It is during this time of the year the birds breed and the heronry becomes lively with the calls of the nestlings and adults.
Experts said that even though black-crowned night herons had almost vanished from the Yamuna floodplains long ago, possibly due to the loss of habitat and the river’s rising pollution levels, they have started setting up colonies over the past few years and have been breeding in the YBP. Now, their population is growing every year.
Park authorities are elated that even the intermediate egrets have started breeding this year, indicating that all is well with the park’s wetland ecosystem.
“This is one of the largest heronry in Delhi, and the black-crowned night herons breed during this time of year. They have built nests all along the 1.8 km-long water body. They were spotted in large numbers and their calls could be heard from a distance. For the first time, we have spotted nests of intermediate egrets this year. This is a welcome sight as birds would breed only in that habitat which they find most suitable,” Faiyaz A Khudsar, scientist-in-charge of the YBP, said.
In 2016, park authorities spotted around 2,000 nests, which shot up to at least 2,500 in 2017. This year, scientists are expecting around 5,000 nests in the park.
Park authorities are now planning to monitor the birds — particularly the black-crowned night herons — around the clock to understand their nesting ecology and feeding habits.
Even though the huge colony has several species such as snake birds, cormorants, egrets, pond herons and grey herons, black-crowned night herons dominate the park’s heronry.
“Night herons usually breed on trees found along water bodies. They can be found in Sultanpur, Okhla and even Delhi zoo. But the heronry in the YBP is possibly the largest in the city. They were also found along the river Yamuna earlier,” Nikhil Devasar, founder of Delhibird, said..
Experts said it is a particular kind of forest community that grows along water bodies, which attract these birds. The ecosystem comprises two species of plants — Phragmites and Tamarix. “The birds started breeding once we established the right riparian ecosystem for them with these two plant species. These two plant species need soil with high moisture content and are found only along water bodies. The heronry is growing every year and attracting other related species,” said CR Babu, professor emeritus and head of the Centre for Environmental Management of Degraded Ecosystem (CEMDE) at Delhi University.