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									        Coral Reefs: A Distant Memory?
A Search Into the Threatened Ecology of Reefs Around the World

     “In order to protect the future of our world, we need to pay attention
        to what is befalling this incredible natural wonder and help to
                   stop the destruction before it is too late.”

                                        -Karen Peterson, Seacology

                                   Riva Kahn

       There is something very familiar yet distant about coral reefs. If you look down at a

healthy reef when snorkeling or diving, you will see a frenetic and busy city. We can recognize a

certain connectivity between organisms; each is struggling for personal resources and security

while helping others thrive. Fish weave in and out of the coral-built substrates, searching for

food. Male seahorses glide cautiously around the coral, guarding their young. Wrasses hover

inside groupers’ mouths to help clean the larger fish’s gums and gills and receive a meal in

return. The place is buzzing with creatures doing jobs and contributing to the good of the reef.

We can relate to all this; we live in a society where connections and bustling networks are vital.

But because many of us do not visit this underwater world every day, we are detached.

   The distance between our society on land and the submerged realm of the reefs creates a

physical barrier, causing thoughts of these complex systems to migrate towards the back of our

minds. I know people who see the value of working for humanitarian causes but do not seem to

think that ecology merits the same level of urgency. People who truly realize the criticality are

generally the ones closest to the reefs. These include scientists, divers, and most of all, people

living near the reefs who depend on oceanic resources for food, trade, development, and survival.

If the rest of us do not become more aware of the reefs’ conditions, it may not just be the coastal

communities that will suffer. Dr. Steve Webster, a scientist and teacher who has been studying

the reefs for years, sees a bigger picture: “The same factors that would lead to the demise of

coral reefs will also cause huge dislocations in global freshwater supplies, food production,

disease distributions, bird migrations, major storm severity, and on and on” (Webster interview).
This is why many scientists think of coral reefs as the canary in the coal mine, or an early

warning system for an even graver danger ahead. Humans cannot justify the reefs’ rapid

disappearance by saying they are fragile. These complex ecosystems have been around for over

400 million years and have been able to adapt to change in the past ( What will

ultimately wipe out the coral reefs is the magnitude of different assaults on their biome. Almost

all of these can be traced back to humans, and will not relent anytime soon if we maintain such a

distant connection to the beautiful and intricate underwater societies.

   The loss would be unfathomable. Although corals only cover 1% of the ocean floor, they

support 25% of ocean life (Epatko). They are richly abundant and diverse; they provide a

nursery, shelter, and food for over 1 million species (Merriam 13). Reefs could be an important

source of medicine to cure human diseases from arthritis to cancer. Buffering the shore from

storms, erosion, hurricanes and destructive waves, coral reefs protect coastal communities.

Allowing the extinction of coral reefs could unleash other unforeseen imbalances in the ecology

of our planet.

   Before I knew that coral reefs were in such peril, I used to thumb through photography books

of vivid coral that seemed other-worldly. I was mesmerized by the beauty of saltwater tanks. I

kept an aquarium with fish, plants, shrimp, and snails and loved every minute balancing the

ecology inside. I had the experience of snorkeling on Hawaiian reefs where elegant everyday

lives were taking place right before my eyes. When I did learn that such extraordinary and

valuable ecosystems could become extinct in only fifty years, I wanted to find out more. From

this search stemmed many questions: How can the coral reefs be dying on such a massive scale?
What is specifically causing this? Is it already too late to save the reefs, and if not, what can we

do? What are the temporary and long-term ways to reverse the trends? To explain the complex

answers to these (and other) questions, I turned to scientists who all study sea ecology, each

bringing their own expertise.

   The five I interviewed had slightly varying assessments about the state of coral reefs,

depending on their field of work. First, I contacted a few organizations and received a reply from

Karen Peterson of Seacology. She provided information about coastal communities, since

Seacology is an organization that helps people reorganize their countries’ economies to support

local ecologies. Next I called Professor Roy Caldwell, an invertebrate specialist at UC Berkeley.

He told me about the coral animals themselves and about his research into ways of

reconstructing the damaged reefs. My personal interview was with scientist and teacher Dr.

Steve Webster, an invertebrate zoologist and also one of the founders of the Monterey Bay

Aquarium. He gave me over an hour of his time to discuss what is killing the coral, the current

condition of the reefs, and their future. He was leaving for Fiji the following week. When I

returned from my trip to Monterey, a message was waiting for me on my machine from Matt

Wandell of the Steinhart Aquarium. The California Academy of Sciences is being relocated

where they will be installing a 212,000 gallon coral reef tank. I asked him about what he has to

study to keep the corals alive during transportation, hoping to discover how fragile the animals

are. Finally, I interviewed my uncle, Ian Kaplan, who was a professor of geology at UCLA. He

did a sabbatical in Australia and New Caledonia studying the water around coral reefs. Since he

is a geologist, he helped me understand the formation of reefs and the detailed chemistry of why

they are dying. I tried to fill in the gaps of my research (such as statistical data, diagrams and
picture documentation, and economics) with books and articles. No matter what field of

specialty, all of my interviewees and research reiterated the same thing. The sustained, diverse,

and stunning ecosystem of the coral reefs and everything that depends on them is being

threatened by the rampant growth of our own society while we go on, removed from the urgency

of the situation.

    If you look closer at coral, it is possible to see many—thousands, even— individual coral

polyps that form the larger reef. These polyps are actually animals (some anthozoans, some

hydrozoans) varying in diameter from the size of a pinhead to a large dinner plate

( Each animal can be described by a few basic features. Polyp stocks are encased

in an epidermis and topped with a circle of tentacles. In many species of coral, these tentacles

catch microorganisms and phytoplankton that feed the mouth within, but other species extract

nutrients directly from the seawater (Wandell interview). The tentacles of all coral clear debris

away from the mouth, and the toxins inside the tentacles serve as the main defense mechanism

( Inside the polyp lies the coral’s digestion system, a home for a symbiotic algae

called zooxanthellae. As long as the amount of zooxanthellae is kept at a healthy level, the

symbiosis will continue; the polyps will provide some nutrients for the zooxanthellae (

and will offer a safe surface for the algae to attach and photosynthesize (Kaplan interview). Once

the zooxanthellae photosynthesize, the nutrients the algae generates will be used by the coral as

food and the energy derived from these nutrients will act “as building blocks in the manufacture

of proteins, fats, and carbohydrates” ( Reef-building corals also treat this energy

as fuel in their process of creating calcium carbonate (CaCO3); they extract calcium (Ca) and

carbonate (CO3) from the seawater, using the energy to bond the two ions into calcium carbonate
(Wandell interview). As these corals grow, they secrete this calcium carbonate as “tiny skeletal

cups. The large masses of corals in reefs are actually colonies of polyps whose external skeletons

are fused together” ( All kinds of corals secrete calcium carbonate, but certain

corals are not reef-builders.

   There are two categories of coral: soft and stony. Soft corals are flexible and wave in the

current at depths of up to 3 km, providing shelter for other organisms (Maman 12). The bright

color of the algae within shines through the transparent tissue of soft corals, giving the corals an

elegant radiance. Hard corals, typically called stony corals, make up the majority of coral species

( Most stony corals have very small polyps, usually the size of a fingernail but

much heavier ( Though small, these polyps can build reefs weighing several tons

by making their own calcium carbonate substrate (Wandell interview).

   Corals can build structures hundreds of miles long in either fringing, atoll, or barrier

formations. Fringing reefs, the most common formation, are built in shallow water around land,

“fringing” the coast (Kaplan interview). They are found directly offshore, usually around islands

such as Hawaii. When the coral runs parallel to a land mass, we call it a barrier reef (Kaplan

interview). A lagoon often forms in the distance between the barrier reef and the shore

( The most famous example is the Great Barrier Reef of Australia, which extends

for over 1,250 miles (Frail 93). Circular structures formed around the top of sunken land masses

such as volcanoes or guyots (flat-topped volcanoes) are atolls. The reef continues to grow

upwards towards the light as the land erodes, so water fills the craters that form in the middle of

atolls (Kaplan interview). This type of reef can be seen around Pacific islands such as Bora Bora.
It is likely that you will see a coral reef if you are traveling near a tropical to semitropical coast,

especially between 30˚ north and south longitude (

    Coral reefs of all types can be found in Australia, Hawaii, the Caribbean, the Indo-Pacific,

around islands in the South Pacific, and off the coast of East Africa. Though the structures can be

large and impressive—they are the only natural structures visible from space—their permanence

cannot be taken for granted. As Paul Eccleston wrote, “Almost 600 square miles of reef have

disappeared every year since the late 1960s, [which is] twice the rate of rainforest loss”

(Eccleston). We are learning that this is due to a variety of global and local stressors. The most

harmful attacks are causing the corals’ symbiotic zooxanthellae algae to die, which in turn is

killing the corals. None of these majestic reefs could exist without the right amount of algae

living inside each polyp.

    If either too little or too much algae is living in the coral polyps, the effects can be

devastating. The vibrant colors you see in coral can bleach bone white if the algae endures

stressful temperature fluctuations. “Photosynthesis pathways in zooxanthellae are impaired” if

temperatures exceed 86˚ Fahrenheit (Buchheim). At our current rate, global warming would

cause the oceans to rise by 1-2˚F in the next century, which may prove to be too much of a

temperature jump for the corals (Caldwell interview). According to Dr. Webster, “If it’s too

severe a temperature rise, or too prolonged, [the corals] don’t recover” (Webster interview). A

mass bleaching happened in Fiji after the El Niño warming period and only certain corals came

back. On the other extreme, fertilizer runoff from agricultural farms can cause algae to grow too

much, smothering and possibly killing the corals. Today, this can be seen all over the Caribbean
and in the Florida Keys. Runoff often “nutrif[ies] the water, and that fertilizes the algae... so lots

and lots of reefs are now 80% algae, 20% coral, whereas thirty years ago it was 80% coral, 20%

algae” (Webster interview).

   But rising temperatures and pollution are by no means the only stressor on coral reefs.

Acidification is another; it alters the chemistry of the coral reefs themselves. When we pump

carbon dioxide into the air, it dissolves into the ocean water and forms carbonic acid. The coral

reefs, as you may remember, make their own substrate out of calcium carbonate. When these two

substances come in contact, the substrate is turned to calcium bicarbonate, Ca(HCO3)2 (Kaplan

interview). Unfortunately, calcium bicarbonate is very easily dissolved by acid. “Ocean

acidification is affecting— can affect— everything that secretes calcium carbonate; shells,

bones, exoskeletons. Well, what is a reef-building coral? Massive [calcium] carbonate

exoskeletons” (Webster interview). If the amount of carbon dioxide we emit continues to

increase, the base of the reef and all the aragonite-based shells in the ocean could eventually

dissolve away. According to Dr. Steve Webster, this problem can only be solved by regulating

global carbon emissions caused by factories, cars, and the process of generating electricity.

   In addition, reefs are also under stress from coastal inhabitants, more than 100 million of

whom ironically depend on them directly for resources and tourism (Chekchak 18). To feed the

growing populations of the world, fish has emerged as an important source of protein. Dried fish

especially is considered a staple in many areas; it is an invaluable food, perfect for trade since it

preserves well (Chekchak 18). Harvesting fish and other resources would be sustainable enough

if the communities fished predators and prey in balanced, moderate amounts. However,
overfishing and various destructive methods of fishing are raising concern among some

scientists. Sometimes cyanide and bleach (both poisons), dynamite, and massive nets are used to

harvest as many fish on a reef as possible, especially as fish are rarer and harder to find. As the

volume of production decreases, fishing becomes more destructive (Caldwell interview). These

activities are destroying and poisoning the coral reefs and throwing off the sublime balance of

the ecosystem. Professor Roy Caldwell at UC Berkeley thinks that these modern, aggressive

fishing methods might have such a powerful effect on the food webs of our world that it will be

the most dangerous threat for corals (Caldwell interview).

   However, Dr. Steve Webster does not entirely agree; he says, “Countries are beginning to get

the idea that they can do a lot better with tourism dollars than they do blasting the reefs and

getting those last few fish. So, fortunately, that is becoming less common” (Webster interview).

Until recently, the culmination of pollutants, destructive fishing, poor development planning, and

harmful recreational activities that come with tourism have impacted the reefs. Karen Peterson

told me that her organization, Seacology, “work[s] with these communities to encourage them to

manage their resources in such a way that there will be plenty left for future generations”

(Peterson interview). For the sake of the coral reefs, I hope the latter two scientists are correct.

   The slew of problems that is weakening the coral reefs today seems proportionate to the

higher level of human activity. The health of the coral is declining because of our impact,

making the reefs “susceptible to bacteria, fungi and viruses in the water. During the last 10 years,

coral disease has increased dramatically” (Maman 16). Scientists and others have made— and

still are making— desperate attempts to at least temporarily slow the coral reefs’ disappearance
until we can solve the long-term crisis. Professor Caldwell discovered that although parts of the

reefs were reduced to rubble by dynamite, there were polyps that survived. He fixed the living

polyps to a slab of limestone from a quarry, and sure enough, the coral started to grow back.

However, he told me that he did not continue with this project because it was neither

economically possible to save reefs around the world in this way nor was it possible for the coral

to live very long (they would still have to face acidification, rising water temperatures, and many

other attacks) (Caldwell interview). Another endeavor to seed a new reef and promote sea life

was in the early 1970s, when “over 2 million tires were dumped into the Atlantic Ocean off the

coast of Ft. Lauderdale” (Allen NPR). Unfortunately, instead of creating a new reef habitat, the

tires were pushed onto a nearby coral reef by storms, “essentially denuding that one, eliminating

all the corals” (Allen NPR). I wondered about other options, so I asked Dr. Steve Webster if it

was somehow possible to inoculate bleached corals with their symbiotic algae. He said no, it was

too massive a project. I kept trying. Can we neutralize the acidity? Again, the answer was no, the

ocean currents were too vast and we would only be able to affect local areas. So, I inquired, it

would be better to take sweeping, global actions such as regulating carbon emissions? “Exactly,”

he said, “exactly” (Webster interview).

   Ecosystems including the coral reefs have been able to adapt throughout geological time.

Some might say this phase is no different, that there is no reason to take such drastic measures at

the expense of socioeconomic development. But this is not the case. “There have been times in

geological history when there has been a lot more CO2 in the atmosphere than there is today, and

it’s been a lot warmer than it is today. But we didn’t have six billion people going on nine billion

then the way we do today” (Webster interview). With the stress of a soaring human population
and the toll it could take on our Earth, the coral reefs will be among the first casualties. We give

them no time to adapt. Even in 1999, the underwater photographer David Doubilet wrote, “There

is a dark side to these seas of dreams... A reef can support a village of one hundred but the same

village is now one thousand and the economy has shifted from subsistence to cash... In the heart

of the ocean, we are in a race between discovery and destruction” (Doubilet). The coral reefs can

teach us how important it is to control our growth and strike a sustainable balance. “The

abundant life of a coral reef is a tribute to the recycling powers of the community. Coral reefs

grow in nutrient-poor, tropical waters, an oasis of life in a desert, a community of animals which

recycles all available nutrients to near-perfection” (Wu 103).

   There is so much to learn from these beautiful and efficient systems, and we can take

measures to ensure their survival and ability to teach our future generations. According to the

2008 International Year of the Reef publication, “to give [the reefs] a fighting chance to survive”

(Maman 15), we must gather knowledge through documentaries, visiting aquariums, supporting

research, and reading. The next step is to circulate this knowledge; talk to teachers and

classmates, volunteer to teach conservation, and ask family and friends what they know about the

coral reef crisis. Next “fire up the political will” (Maman 15) by petitioning the government to

reduce reef threats, fund research, and monitor seafood sources for sustainability. Finally,

“develop a sense of stewardship” (Maman 15) by joining reef and beach cleanups, conserving

water, and reducing your carbon footprint by driving less and saving power.

   Though I may not be able to dive on a reef in Batangas, Philippines or near Sangalakki

Island, Borneo, I can continue to narrow the distance by building on what I know now, by
keeping in touch with the scientists who have been enthusiastic mentors, and by acting on all I

have learned.
                                         Works Cited

Buchheim, Jason. Coral Reef Bleaching. Odyssey Expeditions. May 2008


Caldwell, Roy. Telephone interview. Apr. 2008.

Doubilet, David. Afterword. Water Light Time. By Doubilet. N.p.: n.p., n.d. N. pag.

Eccleston, Paul. “Coral Reef Loss at Unprecedented Levels.” Telegraph 8 Aug. 2008. May 2008


Epatko, Larisa. “Threats and Remedies.” Coral Reefs. PBS. May 2008 <


Fallout from Bad „70s Idea: Auto Tires in Ocean Reef. Natl. Public Radio. KQED. 5 July 2007.

       Transcript. May 2008 <


Frail, T.A. “Great Barrier Reef.” Smithsonian Jan. 2008: 93.

“How Does a Coral Reef Grow?” Earth and Sky. May 2008 <


Kaplan, Ian. Telephone interview. Apr. 2008.

Merriam, Clark Lee, et al. “International Year of the Reef.” Calypso Log Mar. 2008: 12-19.

Peterson, Karen. Email interview. 9 Apr. 2008.

Thurman, H.V. “Essentials of Oceanography.” Indiana University-Purdue University

       Indianapolis. May 2008 <


Wandell, Matt. Telephone interview. 17 Apr. 2008.

Webster, Steve. Personal interview. 10 Apr. 2008.
“What are Corals and Coral Reefs?” Coris. NOAA. May 2008 <


Wu, Norbert. Afterword. Splendors of the Sea. By Wu. N.p.: n.p., n.d.

                                        Works Consulted

“Aragonite (Calcium Carbonate).” Amethyst Galleries‟ Mineral Gallery. May 2008


Azeez Abdul Hakeem, Abdul. “Scientists Protect Corals from Warming Oceans.” Interview with

       Jon Hamilton. Climate Connections. Adaptation. Natl. Public Radio. 22 Oct. 2007.

       Transcript. Mar. 2008 <


Buchheim, Jason. Coral Reef Bleaching. Odyssey Expeditions. May 2008


Caldeira, Ken. “Predicting the Future of Reefs in Peril.” Interview with Ira Flatow. Talk of the

       Nation. Science Friday. Natl. Public Radio. 14 Dec. 2007. Transcript. Mar. 2008


Caldwell, Roy. Telephone interview. Apr. 2008.

Dean, Cornelia. “Coral Reefs and What Ruins Them.” New York Times 26 Feb. 2008. 26 Mar.

       2008 <


Doubilet, David. Afterword. Water Light Time. By Doubilet. N.p.: n.p., n.d. N. pag.

Eccleston, Paul. “Coral Reef Loss at Unprecedented Levels.” Telegraph 8 Aug. 2008. May 2008

Epatko, Larisa. “Threats and Remedies.” Coral Reefs. PBS. May 2008 <


Fallout from Bad „70s Idea: Auto Tires in Ocean Reef. Natl. Public Radio. KQED. 5 July 2007.

       Transcript. May 2008 <


Frail, T.A. “Great Barrier Reef.” Smithsonian Jan. 2008: 93.

Global Coral Reef Alliance, and Environmental Solutions International. A Guide to Protecting

       Coral Reefs. May 2008 <>.

“Hawaii Coral Reefs.” Monterey Bay Aquarium Research Institute. Mar. 2008


“How Does a Coral Reef Grow?” Earth and Sky. May 2008 <


Kaplan, Ian. Telephone interview. Apr. 2008.

Marine Biology Coral Reefs. Dept. home page. State University of New York at Stony Brook.

       Mar. 2008 <>.

Merriam, Clark Lee, et al. “International Year of the Reef.” Calypso Log Mar. 2008: 12-19.

Peterson, Karen. Email interview. 9 Apr. 2008.

Thurman, H.V. “Essentials of Oceanography.” Indiana University-Purdue University

       Indianapolis. May 2008 <


Wandell, Matt. Telephone interview. 17 Apr. 2008.

Webster, Steve. Personal interview. 10 Apr. 2008.
“What are Corals and Coral Reefs?” Coris. NOAA. May 2008 <


Wu, Norbert. Afterword. Splendors of the Sea. By Wu. N.p.: n.p., n.d.

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