Thiruvananthapuram: Kerala, with its long coastline, has a major chunk of the population having fishing as their means of livelihood. While it’s no secret that the sea, like the land, has caves, mountain ranges, and rocky terrains, these underwater formations still hold many mysteries.
One such fascinating marine phenomenon is the ocean floor, which fishermen affectionately call “paars” (reefs or rocky beds). These vibrant ecosystems are now under serious threat from what fishermen refer to as "ghost nets." Ghost nets are fishing nets lost or abandoned at sea during fishing. These nets, either accidentally lost or intentionally discarded by fishermen, are carried away by tides or strong currents and eventually settle on the seabed.
According to Johnson Jamath, a marine researcher and member of Friends for Marine Life, these ghost nets have become a major hazard to the marine ecosystem.
Just like the Western Ghats are a reservoir of biodiversity on land, these underwater rocky beds are rich in marine life. When a net falls over them, it’s as if a ring is thrown over a mountain. According to Johnson, around 80% of marine life lives on or near the seabed. When nets fall and settle there, marine organisms get trapped and die as they can’t escape.
These ghost nets also pose a serious threat to coral reefs, often referred to as the “secret cities of the sea,” which they can entirely destroy. Numerous other forms of waste also end up on the ocean floor. These, when caught under or around the ghost nets, get trapped and can’t disperse. Over time, layers of debris, including plastics, accumulate around the nets, forming underwater waste mounds that severely affect the marine ecosystem.
Complete removal of ghost nets is nearly impossible, says Aneesh, Research Assistant at the Kerala Biodiversity Board who is overseeing a project to remove them. Many parts of the sea are littered with ghost nets stretching over kilometres. Nets get trapped not only during fishing but also when abandoned onshore or swept into the sea during storms or high tides.
Nylon nets, widely used today, can last up to 600 years on the seabed without decomposing. Until the 1970s, fishermen in Kerala mostly used cotton nets, which were environmentally friendly and would not cause harm even if discarded into the sea. After the '70s, nylon nets became popular due to their low cost.
Today, fishing nets are available at prices starting from ₹20,000, with costs varying based on size and mesh type. Only boats registered with Matsyafed (a fisheries cooperative) are legally allowed to purchase nets using this registration. However, illegal sales of cheaper nets from Tamil Nadu are rampant in Kerala.
Pilot Project with ₹10 Lakh for Removal:
A pilot project worth ₹10 lakh has been launched by the Kerala Biodiversity Board to remove ghost nets. The Central Marine Fisheries Research Institute (CMFRI) identified ghost nets in the Vizhinjam and Kovalam coastal areas for this first phase.
Many traditional fishermen in the area practice a form of fishing called kakkavara. The knowledge and experience of these traditional fishermen will be used to locate ghost nets on the seabed, which will then be removed with the help of scuba divers.
Ghost nets can only be removed from areas up to 100 meters deep. CMFRI will conduct a study both before and after the removal to assess the ecological impact, and a detailed report will be submitted to the government.
Artificial Reefs Turning into Trash Mounds:
Artificial reefs are sometimes deployed without consulting traditional fishermen. According to Johnson, these structures often become entangled in ghost nets and turn into waste mounds. While marine researchers working with government agencies have access to GPS data for artificial reefs, fishermen have no such information.
Traditional fishermen have a good understanding of where natural reefs are located. They only use hooks and lines (not nets) to fish in these areas. Net fishers usually avoid such spots. However, due to a lack of information, some throw nets over artificial reefs, which then get entangled and become ghost nets themselves. Thus, artificial reefs intended to boost fishing may end up harming marine biodiversity, Johnson added.
