The unprecedented August 2018 flood has washed out a huge amount of plastics from the land and rivers into the ocean, threatening marine life and underwater ecosystem. Now, scientists have come across evidence that migratory birds are also victims of the plastic discards.

Nisanth, a research scholar working on pelagic birds of Kerala, has documented the serious implications of plastics on seabirds visiting Kerala in this season. He recorded the case of a Lesser Black-backed Gull or Heuglin’s Gull (Larus fuscus heuglini) with a plastic bottle ring caught in its beak. The species is a winter visitor to Kerala and was seen at Ponnani.

The ring had pierced the bird’s beak and formed a ring around its eyes, obstructing its vision during flight. According to Mr. Nishanth, the ring could have got tangled on the bird’s beak while it was feeding on fish from the sea or picking worms from the beach. Heuglin’s Gull breeds in the tundra of northern Russia and migrate south to southwest Asia, including India during winter.

Scientists feel that nylon fishing nets thrown back into the ocean (often referred to as ghost nets) or carried out to the sea during the flood could also pose a serious hazard for marine life. A Lesser Crested Tern (Thalasseus bengalensis), a winter visitor to Kerala and found at Thottappally in Alappuzha, was documented with a discarded gill net wrapped around its beak, limbs and wings.

“In both cases, the plastics found on the body of the bird seemed to have affected their behaviour, as they have to feed on the discarded food from other birds in the flock,” Mr. Nishanth says. “This seems to have forced them to depend on other members of the same species or even different species for food and to escape from predators.”

Ingesting plastic

The sight of seabirds ingesting plastics is on the increase in Kerala, especially during the period from November to February when migratory species visit the State. Similarly, discarded fishing gear, including nylon nets and cut lines with hooks, often becomes lethal for seabirds.

“We need concerted action to manage plastic pollution in our coastal waters and an urgent intervention to ban single use plastics in Kerala,” says A. Biju Kumar of the Department of Aquatic Biology and Fisheries, University of Kerala, who supervised the research.