Coral Reefs: How Humans Have Devastated the Rainforests of the Ocean

Tonight’s Fish Tank Kings features a customer called Craig who wants Living Color to create a replica of his personal favorite place and one of the top snorkeling spots in the United States, Looe Key.  The reefs there are full of beautiful coral and colorful fish, and it is no wonder that Craig wants easy access to a lookalike.  After all, the actual reef may be gone in a couple years considering that some scientists say that almost all of our earth’s coral reefs may disappear by 2050.  They are less than 1% of the ocean floor, yet they are home to about 25% of all discovered marine species in more variety than just about anywhere else in the world.  Over one million different species of underwater plants and animals rely on coral reefs, yet the vibrancy and life that once thrived in coral reefs all around the world are quickly diminishing.

Francis, the resident Fish Geek, says, “If humans haven’t intervened and impacted the coral reef ecosystem, it would be jam packed with such a big diversity of corals.”  As is, human activity has wreaked havoc on the oceans due to pollution and climate change. In fact, NOAA has categorized two of the three most important Caribbean corals, staghorn and elkhorn coral, as threatened under the ESA, with a proposal in the works to classify them as endangered. The Fish Tank Kings say that around 90% of them have died in the last 20 years, in large part due to human actions that are destroying the rest of our planet as well although not at the rapid rate that they are killing the reefs.  Staghorn and elkhorn are so important because they facilitate reef growth and development, which in turn creates habitats for sea life.  With 90% of those vital corals gone, Caribbean corals have very little opportunity to form, which means that what already exists is dying and nothing else can grow in its place.  This is happening in the oceans all around the world with 20% of the Great Barrier Reef devastated in the past two decades and 90% of the Indian Ocean’s coral dead as well; this means that 25% of sea creatures are in grave danger, as are any animals that feed off those 25% (including us).  If this devastation continues, coral reefs will be the first ecosystem ever to be completely annihilated by humans.

Words in photo: "At Castello Aragonese, a volcanic island off Naples, Italy, healthy seafloor looks like this: a lumpy quilt of red sponges, white barnacles, lilac coralline algae, sea urchins, and (near the center of the photograph) one well-camouflaged fish. It's a tompot blenny." (Photograph from article "Ocean Acidification" / National Geographic Magazine, April 2011, Vol.219, Issue 4)
Words in photo: “At Castello Aragonese, a volcanic island off Naples, Italy, healthy seafloor looks like this: a lumpy quilt of red sponges, white barnacles, lilac coralline algae, sea urchins, and (near the center of the photograph) one well-camouflaged fish. It’s a tompot blenny.”
(Photograph from article “Ocean Acidification” / National Geographic Magazine, April 2011, Vol.219, Issue 4)
Words in photo: "A few hundred yards from the preceding scene, CO2 bubbling from seafloor vents acidifies the water to levels that might one day prevail all over the oceans. Dull mats of algae replace the colorful diversity--"fair warning," says biologist Jason Hall-Spencer." (Photograph from article "Ocean Acidification" / National Geographic Magazine, April 2011, Vol.219, Issue 4)
Words in photo: “A few hundred yards from the preceding scene, CO2 bubbling from seafloor vents acidifies the water to levels that might one day prevail all over the oceans. Dull mats of algae replace the colorful diversity–“fair warning,” says biologist Jason Hall-Spencer.”
(Photograph from article “Ocean Acidification” / National Geographic Magazine, April 2011, Vol.219, Issue 4)

Two of the most severe threats to coral reefs are climate change and ocean acidification which are caused by human actions and pollution, in particular those causing excessive CO2 emissions.  500 billion tons of CO2 have been released since the beginning of the industrial revolution due to burning of fossil fuels and cutting down of forests.  Due to gas exchange between our air and our waters, the oceans absorb anything released into the atmosphere, including 30% of all the CO2 we humans have released into the atmosphere in the past two centuries.  As a matter of fact, they are still absorbing about a million tons an hour.  All of this CO2 has dropped the pH of the ocean’s surface by .1, making it 30% more acidic.  If things don’t change, our waters will be 150% more acidic in 2100 than it was in 1800.  CO2 emissions have also augmented the rise in our climate’s temperature, and the ocean has absorbed around 90% of that excess heat since 1955.  The warming waters are a major cause of coral bleaching because this phenomenon reduces the waters’ concentration of oxygen and also damages the helpful algae that have a symbiotic relationship with coral (they live inside the coral, and the coral feeds them).

Sewage and surface runoff, which is the flow of water across land that can reach the oceans, containing surpluses of nutrients from our lands are also primary causes of the reefs’ deterioration.  Although “nutrient enrichment” may sound like a good thing, it spells disaster for corals that thrive in low nutrient environments while inflating the population of algae that takes up space on the ocean floor, blocking coral reefs from forming in those areas.  The increase in nutrients also hinders coral calcification, thus coral is a lot weaker and more prone to breaking or dying.  Sediments from landfills and dredging are also burying our reefs, not allowing them to grow, spread, or get sunlight that they need to live.  Furthermore, construction itself is taking place on top of some coral reefs—for example, the Great Barrier Reef always seems to be under siege by some company or other who wants to build near to–or even on top of–the precious ecosystem and thereby destroy it.  Oils, pesticides, metals…these are all parts of the terrestrial runoff with which humans are rapidly committing mass genocide on some of our earth’s most precious and important ecosystems.

Words in photo: "The sea star on the left was raised in normal water in Kiel, Germany; the one on the right, initially identical, was raised in conditions that could occur in the Baltic Sea by 2100. Ocean acidification is amplified in some coastal waters by pollution from the land, which fertilizes blooms of microbes that take oxygen out of the water and put in more CO2. The photographs are to scale. The sea star ont eh right weights only a fifth as much as its peer." (Photograph from article "Ocean Acidification" / National Geographic Magazine, April 2011, Vol.219, Issue 4)
Words in photo: “The sea star on the left was raised in normal water in Kiel, Germany; the one on the right, initially identical, was raised in conditions that could occur in the Baltic Sea by 2100. Ocean acidification is amplified in some coastal waters by pollution from the land, which fertilizes blooms of microbes that take oxygen out of the water and put in more CO2. The photographs are to scale. The sea star on the right weighs only a fifth as much as its peer.”
(Photograph from article “Ocean Acidification” / National Geographic Magazine, April 2011, Vol.219, Issue 4)

Just as the Fish Tank Kings created an entire ecosystem in someone’s backyard lagoon, we need to start replenishing that which we have devastated.  Coral breeding farms like the one featured in tonight’s episode are helping us understand more about the coral reefs and how we can make them stronger to combat our environmental effects which cannot be undone.  We can also start “planting” coral from those farms much in the same way we do trees.  The science writer and broadcaster Gaia Vince wrote an article for BBC in which she said:

The El Nino Pacific-warming phenomenon of 1998 killed 98% of the reef around Vabbinfaru, so the scientists there have been able to compare the growth rates for corals grafted on to concrete structures on “desert” patches of seafloor, and those stuck on to the Lotus. Abdul Azeez, who led the Vabbinfaru project, said coral growth on the structure is up to five times as fast as that elsewhere.

This grafting experiment turned out to be a success, but that success will only endure and thrive if we change our own practices in order to reduce CO2 emissions, contaminated runoff, harmful sediment layers, pollution, and coral-crushing construction.  25% of the world’s sea animals are in danger because their beautiful homes are dying at a scarily rapid rate, but we have the ability to change that and protect our earth.

Watch Fish Tank Kings: Pufferfish Palace tonight, Wednesday the 18th, at 10 PM on NatGeo WILD and see how beautiful our reefs can be!