Indonesia: Coral reefs in Bulukumba threatened by sea temperature

Andi Hajramurni, thejakartapost.com 17 Mar 16;

The increase in sea temperature over the last two weeks has bleached the coral reef in waters around Bulukumba regency in South Sulawesi, threatening a massive reef decline.

“Currently, more than 50 percent of the coral located in Bulukumba waters have turned white,” said Nirwan Dessibali, team coordinator of the Marine Science Diving Club at the University of Hasanuddin (MSDC Unhas) Makassar in South Sulawesi.

Nirwan said a team of five students from the Unhas School of Maritime Affairs and Fisheries discovered the bleached coral during a surveillance operation in waters around Tanjung Bira and Liukang Loe Island, Bulukumba, last week. They monitored the temperature of the water for four days, a process which had involved team members diving to depths of between three to 10 meters.

Nirwan said that during the monitoring, the sea surface temperature had reached 30’C, higher than the average temperature of 27’C.

He said MSDC Unhas carried out the monitoring activities as a response to information released by the National Ocean Atmospheric Administration (NOAA), which announced that the sea temperature across half of the archipelago would continue to increase, surpassing the average temperature levels starting from the middle of this year. The Makassar Strait was said to be among areas that would be affected by the increase to sea temperature, in which the highest rise is predicted to be in the waters around Raja Ampat in Papua.

Apart from Bulukumba, MSDC Unhas had also monitored waters around the Spermonde group of islands near Makassar, such as the Samalona and Baranglompo islands. Coral in several areas around the islands had turned white.

Nirwan said the coral reef had turned white because their coral polyps had lost its zooxanthellae algae symbiotic due to the increase in the sea temperature.

He said the increases of sea temperature would continue to occur through the middle of this year and emphasized that those coral reefs which had turned white might die.

“The massive die off will threaten the sustainability of the ecosystem in the coral reefs, especially the sea biota. They will lose homes they need to cultivate,” said Nirwan.

A coral reef expert from the Unhas School of Maritime Affairs and Fisheries, Chair Rani, said that a massive die off would occur if the high sea temperatures continued over the next two weeks.

“We hope that the increase in sea temperature, influenced by trans-Pacific currents, will not continue for much longer,” said Chair.

Studies show that 40 percent of coral reefs in Bulukumba have suffered serious damage, while in South Sulawesi, the damage level has reached 40-70 percent. Illegal fishing practices using home-made bombs, anesthetic agents and trawls as well as sea pollution are among the major causes behind the damage to the coral reefs in the area. (ebf)


Bulukumba coral reefs threatened with extinction
Andi Hajramurni, The Jakarta Post 18 Mar 16;

Coral reefs in the waters off Bulukumba, South Sulawesi are at great risk of dying off as more than half have been affected by coral bleaching caused by rising seawater temperatures.

“Based on a four-day monitoring, we found coral reef bleaching on a massive scale, at around 50 percent,” Nirwan Dessibali, coordinator of the Marine Science Diving Club of Makassar-based state-run Hasanuddin University told The Jakarta Post on Wednesday.

Nirwan conducted the monitoring with four colleagues who are students of the university’s Maritime and Fishery School off Tanjung Bira and Liukang Island in Bulukumba regency, diving at a depth of between 3 and 10 meters.

The observation was conducted as a follow up to a release by the National Ocean Atmospheric Administration (NOAA), which showed seawater temperatures in some parts of Indonesia, including the Makassar Strait, would continue rising this year.

“According to residents in the region, seawater temperatures have risen since a week before we arrived. When we conducted the observation, the seawater temperature reached 30 degrees Celsius, compared to an average of 27 degrees during normal conditions,” Nirwan said.

Besides Bulukumba, the diving club has also conducted surveys in the Spermonde archipelago in Makassar. Several of the reefs there have also been bleached, but not as extensively as in Bulukumba.

Nirwan said the bleaching of the coral was attributed to the loss of symbiotic zooxantela algae in the coral polyps due to rising seawater temperatures.

The university’s Marine and Fishery School coral reef studies professor Chair Rani separately confirmed on Wednesday that if seawater temperatures kept rising in the next three weeks, the bleached coral reefs were highly likely to die as the zooxantela algae could not survive.

“The condition of coral reefs in Bulukumba is dangerous now. If seawater temperatures remain high, or above tolerable levels, the bleached coral reefs will die in a massive way. The marine biota will also be threatened,” said Chair.

The situation could lead to worse coral reef destruction in the region. Now, more than 40 percent of coral reefs in Bulukumba waters are damaged, while in South Sulawesi, the damage amounts to between 40 and 70 percent.

Besides the rising temperatures, the damage is also due to illegal fishing using explosives, poison and trawl nets, as well as sea pollution and poorly managed marine tourism.

Chair said that as well as Bulukumba, several other regions in South Sulawesi were also at risk, especially the Makassar Strait, such as the Spermonde archipelago encompassing several regencies and cities, including Makassar city, Pangkajene Islands and Selayar regencies, where the world’s largest atoll, the Taka Bonerate Marine National Park, is located.

“South Sulawesi is traversed by high-temperature sea currents, but Raja Ampat in Papua is at greater risk because the area initially experienced high seawater temperatures,” he said.

Areas in Indonesia categorized in the first and second alert levels for coral bleaching include Raja Ampat.

The situation is expected to continue until the middle of this year. The seawater temperatures will reach their peak between March and April.

Chair added that if the bleached coral reefs failed to recover restoring them would take over five years due to very slow rate of coral reef growth, growing at only about 14 centimeters annually.

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