Wetlands for a sustainable urban future: A case for Urengkonthou

Rahul Ashem *

Urban wetlands function as a habitat for waterhen as well as large number of threatened bird species. People are neglecting the value and importance of urban wetlands White breasted waterhen (Amaurornis phoenicurus) is widely distributed in urban areas. The bird is seen mostly in marshes, ponds, and fresh water urban wetlands.

They are dark grey birds with a clean white face, breast and belly. The species is protected under schedule IV category of the Wildlife Protection Act, 1972. The IUCN also classified waterhen as least concern in spite indicates indifferent importance given on the health and state of urban wetlands.

The prevalence of waterhen on one hand improves the quality of wetlands habitat within its range, while at the same time; it acts as an important indicator of environmental fluctuations. In the present era, urban wetlands are in extremely bad shape and are in varying degrees of environmental degradation. The destruction of urban wetlands disturbs the ecological services and functions as well as the livelihoods and wellbeing of the people.

Commonly known as Urengkonthou in Manipuri dialect, the bird demonstrates the importance of habitat heterogeneity in wetland richness and abundance. Urengkonthou, enhances choral species by producing distinctive sounds especially at dawn and dusk or during the breeding season.

The bird is a good swimmer and is able to drive and propel themselves with their legs. Sometimes, they fly with limited capability, in the night hours and are capable of performing local migration. During the threat, the bird submerges in water for long time to avoid the enemy.

While foraging, the bird wanders away from water onto dry grassland, agricultural land or meadows. The bird is an important component of the urban wetland ecosystem as they occupy several tropic levels in the food web of wetland ecosystem. The presence of waterhen in urban wetlands is a good bio indicator and a useful model for studying a variety of environmental problems.

'Wetlands for a sustainable urban future', the theme for World wetlands day (2018) notifies to raise awareness on the importance of wetlands in making pathways for a sustainable urban future. Wetlands represent a podium for ecosystem services, supporting maximum biological diversity including floral and faunal species.

They also function as a habitat for waterhen (Rallidae) family, migratory birds as well as people. Many species of small felines also depend on wetlands for food resources and their survival. Therefore, it is important to preserve urban wetlands in order to provide the water birds with specialized microhabitats and different kinds of food sources.

Currently, most of the urban wetlands are lost due to the development and construction of both residential and commercial properties. Urbanization and rising population are factors that have extreme pressure on the urban wetlands. Urbanization can reduce the quantity of wetland habitat and degrade the quality of remnant wetland patches.

These changes place wetland dependent bird species at risk of decline and, consequently, extirpation. People often view urban wetlands as wasteland, available for dumping wastes or lands that should be converted for other purposes. Across the State, wetlands are facing an array of threats, including climate change, overgrazing of livestock, water diversions for agricultural purposes, human use and increased pollution.

The degradation of wetlands releases certain amount of greenhouse gases (GHGs) in the atmosphere leading to the rise in temperature, precipitation and humidity.

Despite being an abundant and widespread species, the waterhen population of urban wetland ecosystem is under serious threats due to various anthropogenic activities. Areas with fewer populations of the species with degraded wetlands are more prone to extinction. The preservation of urban wetlands is crucial for the survival of waterhen because of its omnivorous type of habit in nature.

The waterhen's diet consists of earthworms, adult and larval insects, spiders, small fish, tadpoles and occasionally birds' eggs. The species also feeds on plant matters such as algae, moss, the vegetative parts of reeds and aquatic plants, water-lilies, waterside herbaceous vegetation, trees and cereal crops etc.

Bird communities are useful indicators of wetland ecosystem as they use the wetlands for feeding, roosting, nesting, feeding and rearing young ones. In addition, they play an important role in the nutrient cycles of many aquatic ecosystems. Water hens may not be the most prominent groups which attract people to wetlands but they possess high ecological value of aquatic ecosystems.

Consequently it is vital to understand the underlying causes of the decline in populations and to control these trends in order to prevent the loss of key components of the biodiversity of wetland habitats. Bird conservation practices like shielding bird nests, protecting migratory neighborhoods and providing an eco-friendly environment should be focused on.

Urban wetlands are seen in and around cities or suburbs and include rivers, flood plains, lakes, and swamp areas. They are ecologically sensitive and adaptive systems. It is the need of hour to study and establish their role in provision of ecosystem services as wildlife habitats, carbon sinks, climate ameliorators, controllers of pollution, and for their position in hydrology.

The conservation of wetlands provides significant aesthetic, educational, cultural and spiritual benefits for recreation and tourism. The present scenario shows population decline of white breasted waterhen due to the clearing of wild vegetation, filling of water bodies, change in land use pattern and construction activities.

The same fate is also faced by Purple swamphen (Porphyrio poliocephalus), common moorhen (Gallinula chloropus) and other threatened bird species distributed in the State. Besides, being drastically altered by habitat loss and pollution, the waterhen has proved to be an enduring bird as it still thrives in most of the urban wetland areas.

Restoration of wetland hydrology is extremely an important need for urban wetlands, even though it is also equally challenging. Effective management of existing wetland habitats is a must for conservation of this bird species.