NEW DELHI,: The Okhla Bird Sanctuary has recorded a decline in the bird population from earlier this year, say environmentalists. They have noted that the fall could be attributed to the ill-effects of global climatic change which is having an adverse impact on migration with lesser species diversity and population being sighted in Delhi/NCR.
Ecologist T. K. Roy explains: “The overall disturbance in wetland habitat and high public and vehicular thoroughfare are other reasons.”
The birds at the Okhla Sanctuary were sighted, numbered and recorded this past weekend under a programme organised by the Delhi Bird Community to popularise birding and bird conservation awareness.
“A birding team participated in this popular event at Okhla Bird Sanctuary on December 6 and recorded an overall total 80 species of both water birds and terrestrial birds,” he added.
The final report noted that out of the 80 bird species, 38 species of water birds (13 species of resident water birds and 25 species of winter migratory birds). included three threatened species and a few of the wader species. Forty-two species of terrestrial birds (38 species of resident birds and four species of Indian migratory bird species) were also found.
Bird lovers claimed it is difficult to watch flocks of winter migratory birds easily as most of the species stay in the middle part of the sanctuary/islands due to hyacinth cleaning work except smaller flocks of a few species like common teal, northern shoveler, common pochard, common coot, gadwal and brown-headed gulls in the eastern side during day time.
“Decreasing winter migratory water bird species could be attributed to overall disturbance in wetland habitat due to late cleaning of water hyacinth in the eastern side, heavy public and vehicular thoroughfare and large scale cattle/buffalo grazing,” said Mr Roy. Meanwhile the decrease in the terrestrial bird species is being attributed to over lopping tree canopy on the eastern side, cleaning of ground habitat and increased human activity.