Ornithologists blame it on high-rise buildings and disturbances
KOCHI: Ornithologists who investigated into the reasons of birds abandoning the Mangalavanam bird sanctuary have found that high-rise buildings adjoining the sanctuary are curtailing the movement of birds.
The buildings close to the sanctuary interrupt proper orientation, take-off and landings of the birds. They also cause hurdles in the regular movements of the nesting birds in transporting nesting materials. It is also likely to hinder the movement of birds while bringing food materials to the chicks and fledglings, said a report prepared by P.A. Azeez and S. Bhupathy of the Salim Ali Centre for Ornithology and Natural History, Coimbatore.
Eco sensitive area
The Mangalavanam and the area around it may be declared as an eco-sensitive area and constructions and real estate developments there should be made to follow the guidelines applicable to eco-sensitive areas, recommended the scientists.
It was at the request of the Kerala Forest Department that the ornithologists conducted the study at the sanctuary.
"Mangalavanam is becoming a small island surrounded by tall buildings. As birds cannot land in an area like helicopters or advance fighter aircrafts, it is suggested that the height of the new (proposed) buildings should be restricted to three to four floors," the report said.
According to the ornithologists, who confirmed the reduction in the number of birds in the sanctuary, the striking colours used in some of the high-rises might seem strange to the birds and scare them.
The high, powerful lights fitted on building complexes are also likely to cause fear to birds. Large quantities of domestic waste are drained directly into Mangalavanam. There is also an increase in garbage dumping, which remains unattended for longer periods, in the area. This leads to increase in the number of crows. The large number of crows poses serious threats to eggs and chicks of other birds. Frequent raids by crows are liable to cause the birds to desert the nests, the report said.
Low bird presence
Ornithologists spotted 194 birds belonging to 32 species during the study held in May. Though May is the peak-breeding season of colonial nesting birds like cormorants, herons and egrets in Kerala, no nests could be found during this visit, the report said.
The number of birds observed during the survey was much lower compared to the results
obtained during a study in 2004. During the earlier study, 398 birds belonging to 62 species were spotted, the report said.
The ornithologists have also visited some new colonies of nesting water birds at Thoppumpady. The new colony was developed and became active within the last one or two years. A colony with about 50 Little Cormorants and 10 Night Herons were found on a tamarind tree of approximately 30m height. Almost all nests had recently hatched chicks.
Some of the areas adjacent to the park that are currently under the control of Indian Railways, Bharat Petroleum Corporation Limited, Revenue Department and the Kochi Corporation can be annexed to the Mangalavanam protected area to form a buffer zone.
Some parts of the land owned by the Bharat Petroleum Corporation may be excavated to
form depressions that can be flooded during tidal influx and common local mangroves may be planted along the depressions.
Scientists have recommended studies on wetlands in the vicinity of Ernakulam, documentation of the heronries and colonies of nesting birds in and around the city, ambient noise levels of the area and bird movement pattern in and around the sanctuary.
Controlling of noise pollution in and around Mangalavanam, curbing of dumping of solid wastes, diversion of liquid waste discharges that may flow down to the mangrove area and development of a new parking space away from the sanctuary to prevent the movement of vehicles were also recommended.