Loading ...
Sorry, an error occurred while loading the content.

CARIBBEAN REEFS BLEACHED BY WARM WATER!

Expand Messages
  • Mike Neuman
    Caribbean Reefs Bleached by Warm Water November 03, 2005 — By Associated Press SAN JUAN, Puerto Rico — A bleaching phenomenon caused by unusually warm
    Message 1 of 1 , Nov 3, 2005
    • 0 Attachment
      Caribbean Reefs Bleached by Warm Water
      November 03, 2005 — By Associated Press

      SAN JUAN, Puerto Rico — A bleaching phenomenon caused by unusually
      warm waters is whitening coral reefs throughout the Caribbean,
      raising fears of a large-scale die-off of the organisms, scientists
      said Wednesday.

      The warmer atmosphere has been slowly raising ocean temperatures,
      threatening sea coral that can only live within a narrow temperature
      margin, according to scientists. A slight increase in sea surface
      temperature can induce coral bleaching, killing the coral.

      Recent data gathered by the University of Puerto Rico shows that up
      to 95 percent of coral colonies off the island have been bleached in
      some areas.

      "The concern is that we may be witnessing a massive die-off. Reports
      from Vieques (Puerto Rico), Barbados and many other Caribbean islands
      is grim," said Mary Ann Lucking, director of the Puerto-Rico-based
      conservation group Coralations.

      Possibly the most severe bleaching happened during El Nino in 1998,
      which raised ocean temperatures and changed currents, causing
      bleaching that devastated reefs worldwide. Parts of the Indian Ocean
      lost up to 90 percent of its coral.

      The bleaching occurs when the microscopic plants, or zooxanthellae,
      which live in coral tissue stop working. The zooxanthellae provide
      corals with color and food.

      Without them, corals usually die.

      Since March, the northeast Caribbean has had higher than normal sea
      surface temperatures. The trade winds, which usually help cool the
      sea, were also not as strong as they have been in the past.

      "When the trade winds blow, they usually blow across the surface of
      the water, and cause water from the bottom, cooler water, to rise up
      to the surface, which keep the Caribbean cooler. That didn't happen
      this year and we don't know why," said Lucking.

      Prior to the 1980s, coral bleaching was isolated and appeared to be
      the result of short-term damage from things like storms or pollution.

      But in the past 20 years bleaching has become more common and more
      severe.

      "This is probably the most severe bleaching event that Puerto Rico
      and the U.S. Virgin Islands has ever recorded," said Andy Bruckner, a
      scientist with the U.S. National Oceanic and Atmospheric
      Administration.

      The bleaching process can begin when temperatures are as little as
      one or two degrees above 86F (30C) for an extended period of time
      during summer months.

      Scientists in Puerto Rico say temperatures have been two degrees
      above normal since September, typically Puerto Rico's warmest month.

      "We're seeing species of coral that have never been affected by
      bleaching now suffering a high mortality," Lucking said.

      Some colonies of coral in the Caribbean, which include up to 42
      species of the animal, have become completely white, according to
      scientists in Puerto Rico, according to University of Puerto Rico
      marine biologist Edwin Hernandez. Reefs off the island-nation of
      Grenada are also bleached with up to 70 percent of colonies suffering
      some impact.

      "The threat from this is enormous, we may be losing an incredible
      resource," said Hernandez.

      Worldwide, coral reefs cover about 110,000 square miles (284,300
      square kilometers) -- which is less than one-tenth of 1 percent of
      the world's oceans. But they support more than 1 million species of
      marine life, sustain tourism industries and provide food for
      islanders throughout the tropics.

      Healthy reefs are like undersea rain forests that naturally draw in
      carbon dioxide, helping pull harmful greenhouse gases from the air.
      They also provide medication. AZT, a drug for HIV patients, is
      derived from a Caribbean reef sponge.
      ----------------------------------------------------------------

      Caribbean Reefs Bleached by Warm Water

      Bleaching Phenomenon Caused by Warm Waters Whitening Coral Reefs
      Throughout the Caribbean
      The Associated Press

      SAN JUAN, Puerto Rico - Unusually warm waters are bleaching coral
      reefs throughout the Caribbean, raising fears of a die-off of the
      important organisms, scientists and environmentalists said Wednesday.

      Ocean temperatures have been slowly rising, threatening sea coral
      that can only live within a narrow temperature band, according to the
      experts. A slight increase in temperature can induce coral bleaching
      and eventually kill the coral.

      Recent data gathered by the University of Puerto Rico shows that up
      to 95 percent of coral colonies off the island have had some
      bleaching.

      "The concern is that we may be witnessing a massive die-off. Reports
      from Vieques (Puerto Rico), Barbados and many other Caribbean islands
      is grim," said Mary Ann Lucking, director of the Puerto-Rico-based
      conservation group Coralations.

      The bleaching occurs when the microscopic plants, or zooxanthellae,
      which live in coral tissue stop working. The zooxanthellae provide
      corals with color and food. Scientists say without them, corals
      usually die.

      Worldwide, coral reefs cover about 110,000 square miles, less than
      one-tenth of 1 percent of the world's oceans. But they support more
      than 1 million species of marine life, sustain tourism industries and
      provide food for islanders throughout the tropics.

      Since March, the northeast Caribbean has had higher than normal sea
      surface temperatures. The trade winds, which usually help cool the
      sea, were also not as strong as they have been in the past.

      Prior to the 1980s, coral bleaching events were isolated and appeared
      to be the result of short-term events such as storms or pollution.
      But in the past 20 years bleaching has become more common.

      "This is probably the most severe bleaching event that Puerto Rico
      and the U.S. Virgin Islands has ever recorded," said Andy Bruckner, a
      scientist with the U.S. National Oceanic and Atmospheric
      Administration.

      The bleaching process can begin when temperatures are as little as
      one or two degrees above 86F for an extended period of time.

      Scientists in Puerto Rico say temperatures have been two degrees
      above normal since September, typically Puerto Rico's warmest month.
      "We're seeing species of coral that have never been effected by
      bleaching now suffering a high mortality," Lucking said.

      Some colonies of coral in the Caribbean, which include up to 42
      species of the animal, have become completely white, according to
      University of Puerto Rico marine biologist Edwin Hernandez. Reefs off
      the island-nation of Grenada are also bleached with up to 70 percent
      of colonies suffering some impact.

      "The threat from this is enormous, we may be losing an incredible
      resource," said Hernandez.
      http://abcnews.go.com/Technology/wireStory?id=1275875
      -------------------------------------------------------------
      Warm Waters Threaten Viability of Caribbean Coral Reefs
      By Kenneth R. Weiss And Usha Lee McFarling
      The Los Angeles Times

      The extremely warm ocean waters fueling this season's record
      hurricane season are severely stressing coral reefs throughout the
      Caribbean and might kill 80 percent to 90 percent of the structures
      in some areas, scientists reported Monday.

      These colorful undersea landmarks -- homes for tropical fish and
      magnets for divers and snorkelers -- are turning white, or
      ``bleaching'' in an area extending from the Florida Keys to Puerto
      Rico and Panama because of warmer than usual water that has persisted
      in the Atlantic for months.

      In 20 years of satellite monitoring, said Al Strong, coordinator for
      the National Oceanic and Atmospheric Administration's Coral Reef
      Watch, ``These levels are like nothing we've ever seen. It's twice
      the thermal stress that we've ever seen for corals. We are talking
      extremely high percentage of bleaching and what seems to be extreme
      mortality.''

      Coral bleaching started showing up in the Florida Keys this summer
      and has spread throughout much of the Caribbean. Puerto Rican
      scientists report that 85 percent to 95 percent of the coral reefs
      there were bleached as were 70 percent of the corals in Grenada.

      ``We are the middle of the biggest bleaching event ever recorded in
      the Caribbean,'' said Drew Harvell, an expert on corals at Cornell
      University who saw bleaching in more than half the corals she
      recently surveyed off Panama.

      This year's bleaching episode concerns scientists who have been
      watching a rapid decline of coral reefs around the world. Corals are
      sensitive animals that require clean, clear water that is warm -- but
      not too warm. In recent decades, clouding from excess sediments,
      fertilizer, sewage and other pollutants have taken a toll, while
      overfishing has removed many of the fish that graze algae off reefs
      and keep them clean.

      The Caribbean is known for the fascinating shapes, colors and odd
      features in its many corals. About 80 percent of reefs there have
      been lost in the last three decades, said Nancy Knowlton, a coral
      reef expert who directs the Center for Marine Biodiversity and
      Conservation at Scripps Institution of Oceanography.

      ``We now may be witnessing the rapid loss of (much) of what
      remains,'' she added.

      Coral reefs are the composite of millions of tiny animals, called
      polyps, that build hard exoskeletons of calcium carbonate. These
      skeletons fuse together in exquisite patterns that can resemble elk
      horns, or brain tissue or unfurled fans.

      A coral polyp thrives by absorbing micro-algae and sheltering it
      inside its skeleton. The algae, in turn, produce sugars that the
      corals use as food. This symbiotic relationship fails when ocean
      water gets too warm and the algae either leaves or is ejected. The
      polyp then withers, leaving only a ghostly white keleton that looks
      as if it had been bleached.

      Reefs can recover from bleaching over several decades if they are
      colonized by larvae from undamaged corals nearby. But repeated
      stresses from warming and other environmental assaults can kill
      corals, including colonies that can live hundreds of years.

      The current warming in the Caribbean might be due partly to global
      warming, but scientists attribute most of it to a natural cycle of
      alternating warmer and cooler water that changes every few decades.

      Since 1995, the ocean has been in a cycle of warmer waters and less
      wind shear -- conditions that are prime for forming strong
      hurricanes.

      These warm conditions were last in place from the 1920s to the 1960s,
      when intense hurricanes were more common.
      http://www.dj.com.ve/article.asp?ArticleId=201641&CategoryId=14092
    Your message has been successfully submitted and would be delivered to recipients shortly.