Blue coral invertebrate Heliopora coerulea - Extinction

Blue Coral

Heliopora coerulea

Conservation Status: Vulnerable

Cause of Decline: Climate Change

Location: Ocean

Collection: Invertebrates

FMNH catalogue no. 26

Coral reefs cover less than one percent of the earth’s surface but nearly a quarter of the ocean’s species are dependent on them for food and shelter. They occur most frequently in warm, shallow waters and due to the diversity of life they support, are often referred to as the rainforests of the ocean.

Blue coral is unique as it is the only species in the order Helioporacea and the only in its subclass Octocorallia that produces a massive skeleton, populated with individual polyps. It is most commonly found in the shallow waters of the Indo-Western Pacific and is named after its distinctive bright blue skeleton.

It is no secret that the earth’s coral reefs are under threat, primarily from human action, with an estimated 20 percent already destroyed. The ubiquitous threat of climate change is a major factor, which causes ocean acidification and warming water temperatures – even a one degree Celsius difference in temperature affects the delicate relationship between coral and the algae that inhabit it. This process is referred to as coral bleaching, which occurs when coral polyps lose their temperature-sensitive algae and become almost transparent, revealing their white skeleton. If exposed to extremely warm temperatures for too long, the coral will die from starvation or disease.

Added to bleaching is a long list of other threats to coral: overfishing, the use of cyanide or dynamite in fishing, exploitation for the aquarium trade, urban and industrial pollution, the introduction of invasive species (like lionfish, who eat the reefs), outbreaks of predatory starfish, careless tourism, sedimentation from land erosion and damage from natural disasters.

There are however, some glimmers of hope as scientists continue to study reefs referred to as ‘bright spots’, areas that have far more fish than expected. One such example is Indonesia’s Raja Ampat archipelago. While bleaching has been widespread throughout the reefs in Indonesia’s waters, Raja Ampat is thriving. Scientists have concluded that the extreme temperature variations it experiences – fluctuating between 19 and 36 degrees Celsius – has resulted in a more temperature-tolerant species of algae inhabiting the coral, helping the reef bounce back from bleaching. As such the Raja Ampat reef, if properly conserved, could serve as a ‘seed-bank’ and be the key to the long-term viability of what remains of the world’s reefs.

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