NEW DELHI: The Yamuna may not be a lost cause after all. A heronry that has recently developed inside the Yamuna Biodiversity Park gives an inkling of what its floodplains could be-if sustained in their natural glory. There are about 600-1,000 nests currently on Tamarix trees, also known as laal jhau or salt cedar. This part of the park has wetlands surrounded by dense laal jhau and common reed or Phragmites forest.

These forests are common to any riparian ecosystem but in case of Yamuna they had degraded and disappeared long ago. After scientists started developing Tamarix and Phragmites plantations to recreate the floodplain ecology, this is the first time they are seeing such a large number of nests. One can hear the call of hundreds of chicks from a distance; the trail leading to this dense patch is particularly narrow and difficult but gives a view of nests on almost every single Tamarix tree. The adult birds are seen protecting the chicks by partially opening their huge wings over them. Scientists said they have not seen adults feeding the chicks yet. Surprisingly, many seem to be feeding on their own.

"There are no Tamarix forests in the 52km stretch of Yamuna bank. So there is no suitable habitat for these birds. We created marshes in the park where Tamarix trees can grow. They are fast growing and salt-loving. It took us about five years to create a micro-environment for these birds to breed," said Prof. C R Babu of Centre for Environmental Management of Degraded Ecosystems and the brain behind the biodiversity park.

"This heronry also shows that the natural Yamuna ecosystem can be recreated and that we don't need food courts or large structures on the floodplains for recreation," Babu trenchantly said. A committee appointed by National Green Tribunal and headed by Prof. Babu had recently recommended Delhi Development Authority's riverfront development project which includes food courts, parking lots and other concrete structures be scrapped. Instead a 52km stretch of Yamuna in Delhi and Uttar Pradesh be declared a 'conservation zone'.

Scientists at the park are documenting various aspects of the breeding process at the heronry so that it can be compared with previous records to understand if there is a change in trends. "We have collected an egg from an abandoned nest to measure its size. Their phenology can give us clues into climate change impacts. The data will be very useful in the long run," said Faiyaz A Khudsar, scientist-in-charge at Yamuna Biodiversity Park.

The park, which is a favourite haunt for bird lovers, has become even more important to birders now. Ranjit Lal, environmentalist and bird watcher who visited the heronry on Tuesday, said that the same patch of land used to be deserted in 2002. "It's amazing how the forests have developed. I used to see these birds while walking from Rajghat to Salimgarh only in the early 1980s," he said.

Other flora developed in the park includes mitragyna, adina, thorn forests, ravine thorn forests and acacia woodlands. The park is not open to the general public because it would disturb the fauna there.