Imagine a World Without Corals

The recent article in the May 4, 2007 edition of Science is a good overview of current scientific research going on today. Richard Stone gives a comprehensive summary of the threats facing coral reefs today and focuses on the more recent concern: that of changing ocean chemistry. I would definitely recommend reading the article. However, I want to focus on the title, “A World Without Corals.” What would “ A World Without Corals” mean to us as divers?

Many of us spend a year or longer in anticipation of our next dive trip. If you are like me, you spend that time dreaming of floating through the water and listening to the sound of your breathing mixed with the clicking sounds of a healthy reef – or if you are lucky the far-off sounds of cetaceans. Perhaps you dive in local lakes between dive trips, to keep skills sharp and because it is better than not diving at all. However, very little can compare to the feeling we all get when we jump into the ocean and descend into the world of coral reefs.

Non-divers can see the underwater world in pictures or in movies and documentaries, and they can even see reef fish (and even whale sharks) in aquariums. But unless you have been diving, or to a certain extent snorkeling, you cannot really appreciate the joy of becoming a part of the reef. Whether you enjoy the big creatures or the small, one cannot help but appreciate the beauty and complexity of a coral reef.

At first it is easy to take reefs for granted – to someone who doesn’t know better, they look very much like rocks. Of course as divers, we know better than that – we know that the reefs were built by living organisms. We learned that in our Open Water classes! But still, living or not, coral aren’t really all that interesting to most people: they don’t really move, you can find them everywhere. The interesting things to see on a dive are the bigger things. But take a moment to really think about it.

In the article, Stone writes that “although reefs cover a minuscule fraction (0.1%) of seabed, they are second only to rainforests in biodiversity, sheltering or nourishing up to 9 million species--a third of all known marine life forms--including 4000 kinds of fish.” Without the coral, there wouldn’t be reef fish or any of the other nine million species depend on those tiny organisms called coral. They have built the Great Barrier Reef which can be seen from space! That’s amazing!

Now think about what would happen if the coral were to disappear. You might think that reefs have survived for thousands of years and they will continue to do so. Unfortunately, we do have to worry about whether future generations will be able to experience the same underwater world that we see today.

Coral reefs are threatened in many ways, and as Stone writes, “the main menaces are largely human-wrought.” Everything from pollution, clumsy divers, overfishing and destructive fishing practices to invasive species, damage from hurricanes and a change of ocean chemistry have negative effects on coral reefs. And unfortunately these different threats act synergistically – the sum of the whole is larger than the parts.

The article states that “surveys suggest that 20% of the reefs on Earth, the largest living structures on the planet, have been destroyed in the past few decades. Another 50% are ailing or verging on collapse.” The same article quotes coral specialist Camilo Mora of Dalhousie University in Halifax, Canada as saying “"Reefs are likely to witness a significant ecological crisis in the coming half-century--because of us."

Have you ever been diving in an area that has been negatively affected by humans? Perhaps it was just a gradual change over time - you noticed changes in a dive site that you revisited after several years – perhaps you noticed that there was more algae, perhaps the vis was a little worse, or perhaps there were fewer fish. Maybe the change was not enough to make you think about the causes, but enough to cross the destination off the list for your next dive vacation. You have to find somewhere better next time. What about when there is no better place left - then where will you go?

Have you ever seen an area that has been affected by dynamite fishing? I have. The physical structure of the reef remains, but it is only a grayish brown skeleton. There are no more hard corals, no more fish, and it is silent except for the sound of your breathing – no healthy clicking of shrimp and fish. It is like a nightmare.

If you were to ask me why I care so much about trying to make a difference, I will tell you it is because I have seen what a “World without Corals” looks like, and I cannot sit around and do nothing. I believe that my actions alone may not save the world, but together we can make a positive difference.

Next time you go diving on a coral reef, take a moment to really appreciate what it is that you are seeing. Consider how long it took to get that way – and think about what the world would be like if all of the coral were to disappear.