Ninety-nine bird species that used the wetlands in six SW U.P. districts were identified

Preventing human depredation and maintaining a range of agricultural wetlands, from small village ponds to large lakes, is essential for bird conservation, according to research carried out by two Indian ornithologists.

K.S. Gopi Sundar of the International Crane Foundation and his wife, Swati Kittur of the Nature Conservation Foundation, have examined how wetlands of various sizes dotted across the landscape in south-western Uttar Pradesh could be sustaining diverse bird species.

“There has been an assumption that conserving a few large wetlands would suffice to protect the majority of wetland-associated bird species,” Dr. Sundar told this correspondent. “We decided to empirically examine how far this was true.

The agricultural wetlands were typically small and isolated, with the overwhelming majority coming under the common lands that were overseen by local panchayats, point out Dr. Sundar and Ms. Kittur in a paper published in Biological Conservation recently. Although often only seasonal, such wetlands served to meet many human needs, including the recharge of groundwater, water supplies for agricultural and household use, grazing for livestock as well as providing vegetation and aquatic fauna that could be harvested.

Using satellite imageries, the two of them identified close to 12,000 wetlands in six south-western U.P. districts. They then picked a random sample of 28, which varied in size from 0.06 hectares to over 30 hectares, for detailed study.

The various species of birds at each of these sites were surveyed during January and February this year. During this period, migratory birds would have completed their journey to India and not begun their return migration.

“We found that wetlands of all sizes, occurring at differing densities on the landscape, are necessary for retaining a large number of bird species,” said Dr. Sundar.

Their survey identified 99 bird species that made use of the wetlands. Some, like storks and cranes, preferred the larger wetlands. But about half the species were found only in smaller patches of water.

Protecting large wetlands would therefore only assist a few species that showed clear preferences for such sites but “will not help achieve conservation of the majority of the species on the landscape,” observed Dr. Sundar and Ms. Kittur in their paper.

Preventing all human use of such wetlands was not essential for bird conservation, their paper noted. “Despite prolonged and very high human pressure on the wetlands, Uttar Pradesh’s agricultural wetlands support a high number of bird species. The observed species richness is the highest known for agricultural wetlands in any landscape in south Asia.”

Human misuse of these wetlands was often illegal. That included draining or filling the wetlands and converting them for other activities. Since the vast majority of wetlands in U.P. are tiny and isolated, they could be converted relatively rapidly and required urgent conservation attention, the paper added.

As local communities usually had a strong interest in maintaining the wetlands, supporting local institutions and enforcing existing legal provisions could help protect these water bodies, Dr. Sundar remarked.