Ollie the Octopus on Coral Bleaching & the Great Barrier Reef

Octopus
Ollie the Octopus (photo by Cherilyn Chin)

Ollie the octopus here. I’m back to talk about more pressing problems that our oceans are facing. I previously covered ocean acidification and the
Great Pacific Garbage Patch.

Today I wanted to discuss a recent study I was told about (I’m may be smart, but I still can’t read!). This scientific study concluded that in past 30 years, half of the Great Barrier Reef (off of Australia) is gone. While I live on the same small patch of coral reef inside my cozy den, I still need live coral reefs to house and attract the food I eat!

Why did the Great Barrier Reef die? There are many reasons why, including:

1. Tropical cyclones
2. Crown-of-thorn starfish
3. Pollution
4. Coral bleaching

Coral bleaching is when the symbiotic photosynthetic zooanthellae living in corals expel themselves. They essentially commit suicide. These zooanthellae are very important to the corals, as in return for shelter, they produce food (like plants on land) for the coral. Without the zooanthellae, the corals are more likely to starve to death and die (bleach).

What causes the zooanthellae to die? The most likely culprit is a rise in seawater temperature due to global warming. So what can be done to keep the coral from bleaching? The most important thing humans can do is reduce the carbon dioxide emissions that cause global warming.

The good news is that some scientists are trying to revive bleached coral reefs by implanting live coral fragments onto them. Scientists have also attracted new coral growth to many bleached areas by running low-voltage electricity through a metal grid.

Why are coral reefs important? They are one of the most biologically diverse ecosystems on earth. In fact, 1 in 4 fish found in the ocean lives on a coral reef! And coral reefs only cover 0.1 percent of the earth’s surface!

I’m out of time, so I will cover the other culprits of coral bleaching another day. Ollie the octopus, signing off.

Articles to read:
Half of Great Barrier Reef Lost in Past 3 Decades
Low-Voltage Electricity Reviving Sick Coral Reef