NEW DELHI: Having recently observed the phenomenon of coral spawning at the Lakshwadeep islands, a group of marine biologists will be spending all of Wednesday, a full moon day, monitoring the phenomenon. Spawning corals are supposed to be more active and synchronous on full moon nights. When observed during the day, this reproductive activity generates a spectacular effect of multiple colours on the surface of the sea. The biologists, among them, Subburaman S, claims that this is the first time that such a phenomenon has been scientifically observed on the west coast of India.
Corals, marine animals found on reefs, reproduce by releasing gametes (eggs and sperm) into the water. Scientists who have closely observed the phenomenon say it looks like snowflakes rising from bottom to top. On the surface of the sea, where the gametes fuse to form larvae, the water can turn from pink, purple, green and even brown. The spawning, a phenomenon that has generated interest in rookie enthusiasts and professionals alike, is also colloquially known as " sex on the reef"
Marine biologist Subburaman S was cruising through the clear waters of near the Kavaratti island in the Lakshwadeep last week when he noticed a pink-brown colouration, which is otherwise uncharacteristic. Local fishermen told him it was an oil slick - the kind of pollution plaguing a large number of water bodies and hence a fairly plausible hypothesis. But Subburaman was skeptical. He collected the slick-like sample to test it. It was all serendipity and curiosity. Simply observing the sample under a microscope revealed that it indeed was coral spawn. They then took a chopper to circle around Agatti Island, Bangaram, Thinakara, and Kavarrati and even dove undersea to confirm that it all came from branching corals.
The occurrence is fairly rare. "It only happens once a year for about a month," says Subburaman, who was visiting the region for coral reef transplantation work along with the Central Marine Fisheries and Research Institute (CMFRI). "They reported something like this from Tamil Nadu's Gulf of Mannar some time last year, but on the west coast, this is the first time it has been scientifically reported," Subburaman told ToI over phone from the Bangaram island.
At the Great Barrier Reef in Australia, the month of November sees a great many tourists, the main attraction being the coral spawning that ensues soon after the full moon of the month. It was here in 1981 that the first ever instance of coral spawning in the world was scientifically recorded.
Predicting it, however, is no easy task. "It is hard to pin down what the cue is. Some coral scientists feel it is the full moon night that triggers it, others think it is a chemical release from other species. The temperature too needs to be just right," says Professor B C Chaudhury, Advisor to the Wildlife Trust of India.
In 2010, corals in the Lakshwadeep were reported to have undergone "stress", because of El Nino - an abnormal warming of the waters around the tropical Pacific. The stress refers to coral bleaching wherein corals lose their algal covering and their chances of survival slim down. Coral bleaching was also reported in 2012, though Chaudhury says the reasons are unknown. However, with this spawning, marine biologists are a lot less skeptical now. "The sea temperature had risen at that time and the corals had turned white, losing all resources of life sustenance. But this shows a continuance of life," notes Subburaman.
With this finding, Prof Chaudhury feels something can come of active research in other spots on the West Coast. "We will now closely monitor the area in Lakshwadeep to learn more about coral behaviour in the region. We have spoken to our team in Malwa and Maharashtra to look out for spawning. If it is happening here, it can be happening at other places in the Arabian Sea as well," says Chaudhury.
Corals, marine animals found on reefs, reproduce by releasing gametes (eggs and sperm) into the water. Scientists who have closely observed the phenomenon say it looks like snowflakes rising from bottom to top. On the surface of the sea, where the gametes fuse to form larvae, the water can turn from pink, purple, green and even brown. The spawning, a phenomenon that has generated interest in rookie enthusiasts and professionals alike, is also colloquially known as " sex on the reef"
Marine biologist Subburaman S was cruising through the clear waters of near the Kavaratti island in the Lakshwadeep last week when he noticed a pink-brown colouration, which is otherwise uncharacteristic. Local fishermen told him it was an oil slick - the kind of pollution plaguing a large number of water bodies and hence a fairly plausible hypothesis. But Subburaman was skeptical. He collected the slick-like sample to test it. It was all serendipity and curiosity. Simply observing the sample under a microscope revealed that it indeed was coral spawn. They then took a chopper to circle around Agatti Island, Bangaram, Thinakara, and Kavarrati and even dove undersea to confirm that it all came from branching corals.
The occurrence is fairly rare. "It only happens once a year for about a month," says Subburaman, who was visiting the region for coral reef transplantation work along with the Central Marine Fisheries and Research Institute (CMFRI). "They reported something like this from Tamil Nadu's Gulf of Mannar some time last year, but on the west coast, this is the first time it has been scientifically reported," Subburaman told ToI over phone from the Bangaram island.
At the Great Barrier Reef in Australia, the month of November sees a great many tourists, the main attraction being the coral spawning that ensues soon after the full moon of the month. It was here in 1981 that the first ever instance of coral spawning in the world was scientifically recorded.
Predicting it, however, is no easy task. "It is hard to pin down what the cue is. Some coral scientists feel it is the full moon night that triggers it, others think it is a chemical release from other species. The temperature too needs to be just right," says Professor B C Chaudhury, Advisor to the Wildlife Trust of India.
In 2010, corals in the Lakshwadeep were reported to have undergone "stress", because of El Nino - an abnormal warming of the waters around the tropical Pacific. The stress refers to coral bleaching wherein corals lose their algal covering and their chances of survival slim down. Coral bleaching was also reported in 2012, though Chaudhury says the reasons are unknown. However, with this spawning, marine biologists are a lot less skeptical now. "The sea temperature had risen at that time and the corals had turned white, losing all resources of life sustenance. But this shows a continuance of life," notes Subburaman.
With this finding, Prof Chaudhury feels something can come of active research in other spots on the West Coast. "We will now closely monitor the area in Lakshwadeep to learn more about coral behaviour in the region. We have spoken to our team in Malwa and Maharashtra to look out for spawning. If it is happening here, it can be happening at other places in the Arabian Sea as well," says Chaudhury.
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