PELAKITA.ID – A sudden coral bleaching phenomenon has been observed at Jikomalamo Beach, Ternate, North Maluku.
This alarming news was shared by diver and coral reef practitioner, Moldy Samudera, in the Coral Adoption Network WhatsApp group on Tuesday, February 25, 2025.
Dr. Syafyuddin Yusuf, a marine science lecturer at Hasanuddin University (Unhas), also weighed in on the situation.
According to Dr. Syafyuddin, commonly known as Dr. Ipul, the bleaching event has been visible since November and December last year, following a similar occurrence in Raja Ampat.
“Warm water from the Pacific Ocean first reached Raja Ampat. Now, the news and photos we received indicate that this ocean warming has reached Ternate’s waters,” he stated.
Furthermore, Dr. Syafyuddin explained that Ternate and Halmahera waters are known to be dynamic. However, the recent increase in sea temperature, rising by 2-3 degrees Celsius above normal, is highly concerning.
“This needs continuous monitoring. The condition is alarming for the health of coral reefs. As of February 2025, about 30-40% of the coral in Raja Ampat has already died due to bleaching,” he added.
What is Foliose Coral and Why is it Bleaching?
Foliose coral is a type of hard coral (Scleractinia) characterized by its layered, leaf-like structure.
This broad structure helps maximize sunlight absorption, which is essential for the photosynthesis of symbiotic algae living within the coral. Typically found in stable tropical waters, foliose coral provides shelter and habitat for various marine organisms.
Coral bleaching occurs when corals lose their natural color and turn white due to the expulsion of zooxanthellae—symbiotic algae that supply nutrients and color to the coral.
The primary cause of coral bleaching is rising sea temperatures due to climate change.
When water temperatures exceed the coral’s tolerance threshold, zooxanthellae are forced out, depriving corals of their main food source and turning them white.
Excessive exposure to UV rays also contributes to coral bleaching. High ultraviolet radiation can damage zooxanthellae and induce stress in corals, especially in clear waters with little natural protection from plankton or sediments.
Environmental pollution is another significant factor. Industrial, agricultural, and household waste containing harmful chemicals such as pesticides and heavy metals can damage coral reef ecosystems.
Increased nitrogen and phosphate levels in the water can lead to excessive algal growth, which blocks sunlight from reaching zooxanthellae.
Changes in salinity and ocean acidity also play a role in coral bleaching. High rainfall or freshwater runoff can lower salinity levels, causing stress to corals.
Additionally, rising atmospheric carbon dioxide levels contribute to ocean acidification, which hampers the formation of calcium carbonate necessary for coral growth.
Human activities such as overfishing and uncontrolled marine tourism accelerate coral damage. Destructive fishing practices, including blast fishing and cyanide use, can devastate coral habitats.
Moreover, careless tourist behavior, such as touching or stepping on corals while diving, exacerbates coral degradation.
Foliose coral plays a crucial role in marine ecosystems by providing shelter and protection for various marine species. However, the increasing threat of coral bleaching due to climate change, pollution, and human activities endangers the sustainability of these vital ecosystems.
To mitigate the effects of coral bleaching, conservation efforts must be strengthened. These include reducing carbon emissions, protecting marine ecosystems, and educating the public on the importance of preserving coral reefs.
Written by Denun
