Species diversity and winter migratory water birds increase at Najafgarh Jheel Why there is a decline in number of migratory birds at Sultanpur National Park! These factors lead to decline the number of migratory birds at Okhla Sanctuary Climate Change causes dwindle in the number of migratory water birds Waterbird species diversity decreased in National Zoological Park wetlands Asian Waterbird Census 2023 to be held from January 7 AWC records sharp decrease in water birds at Surajpur wetland