noida the uttar pradesh irrigation departments decision to open the barrage of yamuna to drain out water in october has hit bird lovers hard as it left the okhla sanctuary dry due to which migratory and resident birds deserted it for some time in november when the water level became normal again even though birds started coming their numbers remained less also some species of birds did not turn up at all and went to nearby placesecologist tk roy said that migration pattern of birds depends much on climate change while this is a global trend and not only about okhla sanctuary lack of sufficient water at peak time and encroachment by local youth affected the migration of birds roy said an official of the sanctuary said that degradation of adjacent small wetland habitat for birds in the buffer zone towards noida causes a threat to them due to regular fishing by local youth local residents can also be seen grazing their cows and buffaloes in the sanctuary wetland which disturbs the natural habitat of birds a monthly ecological report of the sanctuary said that there were also instances of people dumping garbage and stealing parts of iron fence of the sanctuaryokhla bird sanctuary ranger ishwar chandra singh said that the sanctuary provides a natural home to resident and migratory birds which find food and a proper environment for breeding here we always keep checking for instances of poaching of birds singh said but admitted local pressure does hinder their task singh said that some water birds including mallard common teal gadwal tufted pochard common pochard common coot northern piltail and others can be spotted in the sanctuary these days lack of birds is not the only thing that has driven out visitors basic facilities like a canteen toilet and availability of drinking water are lacking which visitors often complain about