Pollution and marine ecology
What spiny pufferfish in St Martin’s Island indicates
The government’s various measures to protect the biodiversity of St. Martin’s Island have begun to show results. Recently, a rare long-spine porcupinefish has been sighted in the waters near Cheradia, a detached part of the island. Research teams have also found evidence of crabs, fish, and other species breeding in different areas of the island.
St. Martin’s Island is an 8-square-kilometer coral-rich island in the Bay of Bengal. To its south lies a smaller detached island, Cheradia. On 17 October, during high tide, a fish got stranded on the western beach of Cheradia. Md. Kamrul Hasan, an official of the Department of Environment, was present there.
Approaching quickly, he discovered a rare species of pufferfish. Such fish are usually not easily seen in this area. Its body was covered with spines. While two species of pufferfish were spotted in other parts of the island’s waters, he had never seen this beautifully coloured spiny pufferfish before here. He could not contain his excitement—because the presence of this species is a significant sign of the return of biodiversity to the island.
Md Kamrul Hasan told Prothom Alo that the presence of spiny pufferfish shows that the government’s measures to protect St. Martin’s environment and biodiversity are beginning to bear fruit. As a result, the number of crabs, turtles, and other species on the island is increasing.
The three-year government project aimed at protecting biodiversity is titled ‘Biodiversity and Climate Change Adaptation Project for St. Martin’s Island.’ Activities to create coastal keya plantations on the island’s beaches, install multiple billboards on the sand to raise environmental awareness among locals, identify nesting sites of marine mother turtles, and collect data, conduct training, and carry out research for biodiversity conservation are underway under this project.
Kamrul Hasan is the project director (PD) of this initiative.
Kamrul Hasan said that during the inspection, he saw migratory birds, seagulls, red crabs on sandbanks, and the breeding of snails and shellfish at different points along the beach. However, the beautiful spiny fish on Cheradia beach astonished him.
Led by Kamrul Hasan, a team from the Department of Environment stayed on St. Martin’s Island from 16 to 18 October to observe the island’s condition. During this period, the team toured the entire island, including restricted areas such as Cheradia, Goldia, and Diermatha.
Kamrul Hasan said that during the inspection, he saw migratory birds, seagulls, red crabs on sandbanks, and the breeding of snails and shellfish at different points along the beach. However, the beautiful spiny fish on Cheradia beach astonished him.
This species lives only around St. Martin’s coral reefs, rocky areas, and coastal regions. It preys on hard-shelled mollusks, crabs, and vertebrates. When threatened by larger fish, it swallows water or air, inflating its body like a balloon to protect itself. As the body inflates, its sharp spines protrude outward. The presence of this fish is evidence of the island’s rich biodiversity.
Researchers say the scientific name of this pufferfish species is Diodon holocanthus, also called the long-spine porcupinefish. Its body is light brown, with small black spots that decrease in number with age.
A fully grown fish can reach about 50 centimeters in length. They are found in warm tropical seas and oceans worldwide. The presence of this species indicates that the island’s coral and other marine life are growing undisturbed, suggesting that the island’s ecosystem and environment are recovering.
Nazir Hossain, a member of Ward No. 9 of St. Martin’s Union Parishad, said that while white species of pufferfish are seen throughout the island, the beautiful spiny ones are rarely seen. Their movement is increasing in Cheradia, where they live inside the coral reefs. They survive by feeding on small colourful fish, crabs, shrimp, and shellfish.
Zamir Hossain, a resident of the northern part of the island who has been in the fish business for 23 years, said, “Fishermen’s nets in St. Martin’s waters catch three species of pufferfish. The white ones are about 2.5 to 3 inches long. The black-spotted larger ones range from 12 to 20 inches. The black species with white spots are 6 to 8 inches long. Many people have died after eating these poisonous pufferfish, which is why they are not consumed.
According to the Department of Environment, the ecologically fragile St. Martin’s Island is home to 1,076 species, including corals, algae, turtles, mollusks, shellfish, marine fish, birds, mammals, and crabs.
Environmentalists believe that pollution is decreasing and ecological balance is gradually returning to the island due to tourist restrictions, reduced use of plastics and other products, and other curbing measures of the authorities.