Context: Recently, the Andhra Pradesh Government has directed the GMR Energy Limited to stop environmental hazardous activities in the Kumbabhishekham mudflat like dredging in the Kakinada coast.
Key Points

• The forest department has ordered the removal of the bund around the mangrove cover adjacent to the company’s 220 MW barge-mounted power plant on the Kakinada coast.
• The dredging was being carried out by GMR Energy Limited to shift existing installations.
• The action comes in response to the threat to the mudflat and the mangrove cover and destruction of the prime habitat of birds — endangered Great knots (Calidris tenuirostris), and Indian skimmers (Rynchops albiocollis), which are listed as a vulnerable species.

About Dredging

• Dredging is the removal of silt, sediments and debris from the bottom of lakes, rivers, harbours and other water bodies.
• Dredging is a routine necessity in waterways because sedimentation—the natural process of sand and silt washing downstream—gradually fills channels and harbors.
• Dredging often is focused on maintaining or increasing the depth of navigation channels, anchorages, or berthing areas to ensure the safe passage of boats and ships.
• Dredging is also performed to reduce the exposure of fish, wildlife, and people to contaminants and to prevent the spread of contaminants to other areas of the water body.
• This environmental dredging is often necessary because sediments in and around cities and industrial areas are frequently contaminated with a variety of pollutants.

About Mudflats

• Mudflats or mud flats, also known as tidal flats, are coastal wetlands that form in inter-tidal areas where sediments have been deposited by tides or rivers.
• Most of the sediment within a mudflat is within the inter-tidal zone, and thus the flat is submerged and exposed approximately twice daily. This helps maintain the ecosystem balance.

Significance:

• Tidal flats, along with inter-tidal salt marshes and mangrove forests, are important ecosystems.
• They usually support a large population of wildlife, and are a key habitat for migratory shorebirds.
• The maintenance of mudflats is important in preventing coastal erosion.

Threats: Mudflats worldwide are under threat from predicted sea level rises, land claims for development, dredging due to shipping purposes, and chemical pollution.
About Great Knots (Calidris tenuirostris)

• These are the migratory birds and have breeding habitat in tundra in northeast Siberia.
• It is listed as Endangered in the IUCN Red List of Threatened Species.

About Indian Skimmers (Rynchops albicollis)

• They are also known as Indian scissors-bill.
• It is listed as Vulnerable in the IUCN Red List of Threatened Species.
• They are mainly found in Central India along the rivers or estuaries.
• The bird has a black cap and orange bill that contrasts with the white body.