Until the 1980s, Kolleru Lake was a sprawling shallow body of water. At its deepest point during the monsoon season, the water only reached 10 feet, yet the lake covered a surface area of 904 sq. km. Located in the southeast state of Andhra Pradesh, Kolleru was among India’s largest freshwater lakes. Known for its biodiversity, the lake was a popular stopover for migratory birds, such as flamingos, which fed from the shallows. Humans, too, derived sustenance from the lake: not just a wide variety of fish, but also rice. Local residents would sow seeds in the summer during the monsoon season and then harvest the rice later in the year, when the lake’s boundaries had receded.
– Until the 1980s, Kolleru Lake was a sprawling shallow body of water. At its deepest during the monsoon, the water only reached 10 feet, yet the lake covered 904 sq. km.
– Today, many of the rice paddies farmers used to plant in the lake are gone, and the flamingos are beginning to disappear, too, along with a myriad other bird species.
– As the local carp and shrimp industry expanded, the fish ponds to harvest them have been built farther into the lake, and the water has been severely degraded.
Until the 1980s, Kolleru Lake was a sprawling shallow body of water. At its deepest point during the monsoon season, the water only reached 10 feet, yet the lake covered a surface area of 904 sq. km. Located in the southeast state of Andhra Pradesh, Kolleru was among India’s largest freshwater lakes. Known for its biodiversity, the lake was a popular stopover for migratory birds, such as flamingos, which fed from the shallows. Humans, too, derived sustenance from the lake: not just a wide variety of fish, but also rice. Local residents would sow seeds in the summer during the monsoon season and then harvest the rice later in the year, when the lake’s boundaries had receded.
Today, many of those rice paddies are gone, and the flamingos are beginning to disappear, too, along with a myriad other bird species. Instead, the region is marked with houses, shops, roads, and human-made ponds. On any given day, fish farmers tend to their stocks – tossing feed into the water, extending nets, and otherwise contributing to a growing aquaculture industry centered on carp and shrimp. As this industry has expanded, it has fundamentally reshaped the region’s topography. These fish ponds, once limited to the shoreline and shallows, are now being built farther and farther into the lake. As a result, scientists say, the water has been severely degraded. And not only that: What remains for most of the year cannot rightly be called a lake.
“Open water we can see only during the monsoon period,” said Meena Kumari Kolli, a geography researcher who earned her PhD from the University of Marburg in Germany. Kolli has used GIS mapping techniques to study how the region has changed over the past few decades. Outside of the rainy season, she said, there are now only fish ponds, dry marshlands, and weeds – “the lake actually doesn’t exist.”
Aquaculture is the fastest growing food production industry in the world, according to the UN’s Food and Agriculture Organisation, and India ranks second globally in aquaculture fish production, contributing more than 8 percent of the world’s farm-raised fish. Indian aquaculture has developed rapidly over the past few decades, said Joeri Scholtens, a fisheries researcher and an assistant professor at the University of Amsterdam. Scholtens says that this kind of rapid growth is unique to India and was possible only because of the nation’s abundant natural resources and government subsidies. The subsidies were part of the country’s Blue Revolution, a program initiated by the central government in the 1980s to boost the economy by increasing production of marine products.
That rapid development is a double-edged sword in Andhra Pradesh, India’s top seafood exporter. Local communities overwhelmingly support aquaculture’s expansion, but they also lament the loss of the lake as a source of food and drinking water. Scientists, meanwhile, insist that industry must be curtailed. They point not just to the pollution, but also to the dramatic declines in native fishes and migratory birds. The ecological imbalance will only get worse, they say, if the region’s aquaculture is allowed to expand.
Read more: https://science.thewire.in/environment/how-aquaculture-turned-kolleru-lake-known-for-its-biodiversity-into-fish-ponds/