Coral Reefs are Disappearing

Updated on May 16, 2017

In her 2009 book Sea Sick, Alanna Mitchell writes “The worldwide decay of coral reefs – caused by the pollution from land, too much fishing, nasty practices to capture wild fish for the aquarium trade, and waters that are too hot because of global climate change – has already started to take its toll.”

Source

Coral Reefs a Rich Source of Marine Life

The Coral Reef Alliance points out that “Although they cover only two-tenths of one percent of the ocean floor, these complex tropical ecosystems rival the rainforests in terms of biodiversity, supporting nearly a quarter of all marine species.”

Writing in The Independent Steve Connor says that coral reefs “provide food for about 500 million people around the world.”

Source

Carbon Dioxide Threatens Reefs

According to the Coral Reef Alliance, the burning of fossil fuels releases carbon dioxide and billions of tonnes have been absorbed by the oceans. This has changed the chemistry of sea water making it more acidic. As a result, coral and shell formations are impaired; when the shells stop forming the reef crumbles quickly.

Dr. Jacob Silverman of the Carnegie Institution of Science in Washington has studied this problem and has used a mathematical model to see what rising acidity will do to 9,000 coral reefs around the world.

He told a meeting of the American Association for the Advancement of Science in San Diego and quoted in The Telegraph that “A global map produced on the basis of these calculations shows that all coral reefs are expected to stop their growth and start to disintegrate when atmosphere CO2 reaches 560 parts per million – double its pre-industrial level – which is expected by the end of the 21st-century.”

The atmospheric concentration of CO2 as of April 2017 is 409 ppm; it passed the 400 ppm level in May 2013.

A wasteland of dead coral.
A wasteland of dead coral. | Source

Great Barrier Reef

Off the coast of Queensland, Australia, the Great Barrier Reef is, or more accurately, was one of the world’s great natural wonders. It stretches for 2,300 kilometres and is breathtakingly beautiful. But, the reef is in trouble.

Here’s a report from The New York Times (March 2017), “Huge sections of the Great Barrier Reef, stretching across hundreds of miles of its most pristine northern sector, were recently found to be dead, killed last year by overheated seawater.”

The tiny creatures, called polyps, that form corals are very sensitive to changes in temperature. A rise of one or two degrees Fahrenheit is enough to kill the animals in a process called bleaching. By a conservative estimate, the world’s ocean temperatures have risen 1.5 degrees Fahrenheit since the late 19th century. An additional jump caused by an El Niño effect, as happened in 2016, spells disaster for coral reefs.

The Great Barrier Reef is a huge tourism attraction bringing in billions of dollars of revenue a year and supporting about 70,000 jobs.

Coral Bombing Destroys Habitat and Fish

Among the reefs of the Philippines, Indonesia, Micronesia, and Africa, people are using dynamite to catch fish. Blast-fishers throw pop-bottle grenades into reef areas. The explosion kills everything nearby and the “fishers” retrieve the dead fish that float to the surface, mostly for local consumption. The explosion also rips apart the coral. The structures made by these living corals are very slow growing; some can take centuries to form.

According to Kate McClellan (Encyclopedia of the Earth) “The use of blast devices is economically efficient – a single bomb costs about 1-2 U.S. dollars to build, while the resulting catch is worth between 15 and 40 U.S. dollars.”

Blast fishing has been made illegal in the Philippines, Malaysia and other areas but it still goes on, because it’s difficult to police long coastlines.

Cyanide Fishing for Aquariums

Cyanide fishing first appeared in the Philippines in the early 1960s and, writes Christie Wilcox (Hakai Magazine, June 2016), it “is one of the most destructive techniques used for catching live fish …”

Divers use squeeze-bottles to squirt a solution of sodium cyanide into coral where reef fish hide. The idea is to temporarily stun the fish, net them, and put them into tanks for transport to aquariums for sale. A study has found that almost half the saltwater fish sold in pet stores in the U.S. are caught by cyanide fishing.

Unfortunately, the cyanide kills the coral.

Many other Threats to Coral

The Coral Reef Alliance lists many other activities that destroy coral reefs:

  • Sewage dumped untreated into oceans and fertilizer run off cause massive increases in algae, which blocks sunlight from coral reefs causing them to die;
  • Construction, mining, farming, and logging can all lead to erosion. Particles of soil and dust are carried into the ocean by rivers and can settle on coral reefs, smothering them;
  • Mangrove forests, which protect coral, are being destroyed to make way for shrimp farming and beach development;
  • Coral is sometimes taken for building materials and to make trinkets for tourists; and,
  • The increased ultraviolet radiation from the Sun that comes from thinning of the ozone layer around the planet may contribute to coral reef weakening.

Coral reef locations.
Coral reef locations. | Source

Coral Reefs Disappearing

With all of these impacts it’s not surprising that coral reefs are in trouble. The Coral Reef Alliance says that with 11 percent of reefs already destroyed “Scientists predict that another 32 percent may be lost in the next thirty years if human threats are not reduced.”

Dr. Silverman of the Carnegie Institution of Science says “… these ecosystems, which harbour the highest diversity of marine life in the oceans, may be severely reduced within less than 100 years.”

Source

Bonus Factoids

Defenders of Wildlife says “About one-third of all marine fish species live part of their lives on coral reefs.”

According to Conserve Energy Future “Scientists have discovered that many parts of a coral reef can be harvested to make medications to treat cancers and other illnesses.”

Coral reefs are places of incredible biodiversity second only to rainforests in the variety of species they host. A two-acre patch of coral can contain more species of fish than there are bird varieties in North America.


The red lionfish is a coral reef dweller you don't want to meet. Its poisonous sting is extremely painful though rarely fatal.
The red lionfish is a coral reef dweller you don't want to meet. Its poisonous sting is extremely painful though rarely fatal. | Source

Sources

  • “Coral Reefs in Danger of Being Destroyed.” Steve Connor, The Independent, February 24, 2010.
  • “AAAS: Coral Reefs Could Disappear by the End of the Century.” Richard Alleyne, The Telegraph, February 24, 2010.
  • “Large Sections of Australia’s Great Reef Are Now Dead, Scientists Find.” Damien Cave and Justin Gillis, New York Times, March 15, 2017.
  • “Coral Degradation Through Destructive Fishing Practices,” Kate McClellan, Encyclopedia of the Earth, August 24, 2008.
  • “Fishing With Cyanide.” Christie Wilcox, Hakai Magazine, June 30, 2016
  • Coral Reef Alliance.

Questions & Answers

    Comments

      0 of 8192 characters used
      Post Comment

      No comments yet.

      working

      This website uses cookies

      As a user in the EEA, your approval is needed on a few things. To provide a better website experience, soapboxie.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

      For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: https://soapboxie.com/privacy-policy#gdpr

      Show Details
      Necessary
      HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
      LoginThis is necessary to sign in to the HubPages Service.
      Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
      AkismetThis is used to detect comment spam. (Privacy Policy)
      HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
      HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
      Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
      CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
      Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
      Features
      Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
      Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
      Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
      Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
      Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
      VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
      PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
      Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
      MavenThis supports the Maven widget and search functionality. (Privacy Policy)
      Marketing
      Google AdSenseThis is an ad network. (Privacy Policy)
      Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
      Index ExchangeThis is an ad network. (Privacy Policy)
      SovrnThis is an ad network. (Privacy Policy)
      Facebook AdsThis is an ad network. (Privacy Policy)
      Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
      AppNexusThis is an ad network. (Privacy Policy)
      OpenxThis is an ad network. (Privacy Policy)
      Rubicon ProjectThis is an ad network. (Privacy Policy)
      TripleLiftThis is an ad network. (Privacy Policy)
      Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
      Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
      Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
      Statistics
      Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
      ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
      Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)