Information from the earliest human interactions with reefs came from fossil and archaeological records. Records and logs from the ships of Christopher Columbus, Captain James Cooke and other European explorers provided detailed descriptions of abundance and diversity of coral reef
ecosystems they encountered. From more recent eras, the researchers used data from fisheries and modern ecological studies. 

Large animals declined faster than small animals, the
researchers found. Free-living animals declined faster
than the architectural builders such as seagrass and
corals. At the beginning of the 20th Century, large
carnivores, including sharks, and herbivores such as
manatees were already either depleted or rare in 80
percent of the examined regions of coral reefs. 'Walking
the plank isn't as dangerous as it once was,' said John
Pandolfi, an author on two of the Science papers and a
curator at the National Museum of Natural History,
Smithsonian Institution. 'If I was forced to walk the
plank and jump into the Caribbean tomorrow, it wouldn't
be that bad. Of course there is the risk of drowning,
but it's not like the old days when the risk of being
eaten by sharks was so much greater,' explained
Pandolfi. While the ecological histories show that coral
reefs have been declining ever since humans discovered
their bounty, Pandolfi is not all gloom and doom, in his
attitude or his predictions but believes there is some
hope for the future. However, a co- ordinated,
aggressive, worldwide effort must be implemented soon.

Indonesian fishermen blast the top of a reef, stunning
the fish that survive and sending them floating to the
surface for easy capture. Click the Play button to see
how reefs are destroyed by such techniques.

CORAL REEFS AND FRIENDS

A coral reef's bright colors come from the single-celled
algae called 'zooxanthellae' that have a cooperative
living arrangement with corals. These colorful,
primitive plants use the sun to produce food that they
share with the coral in return for shelter. Coral reefs
grow in the warm, shallow, clear waters of about 100
tropical and subtropical countries. Reefs provide food
and shelter for fish and invertebrates critical to
commercial fisheries. They also protect nearby
shorelines from erosion and attract the tourists that
sustain economies.

Invertebrate animals called corals build the reefs that
bear their name. Corals secrete the limestone that forms
the hard structure of coral reefs. While the building of
coral reefs takes many years, storms and human
activities can rapidly destroy them. Reefs that are
already stressed by pollution and over-fishing have a
harder time rebounding from natural occurrences such as
hurricanes and cyclones. The future of coral reefs
depends on how well humans reduce the pressures of over-
fishing and pollution while minimizing the already
catastrophic impact of ocean warming on coral reefs. The
authors of a second Science study note that some coral
species are showing far greater tolerance to climate
change than others.

DECLINING STANDARDS FOR CORAL REEFS '

People pay hundreds of dollars to dive in reefs so
damaged that seeing them would make me cry,' said Jeremy
Jackson, an author on the two Science papers described
in this story. 'They have no idea what they are missing
or what drastic deterioration has occurred,' said
Jackson, a marine biologist from Scripps Institution of
Oceanography in La Jolla, CA and the Smithsonian
Tropical Research Institute in Balboa, Republic of
Panama. The ecosystem histories the marine biologists
just published are, in some ways, the equivalent to a
person's medical records, according to Jackson. He noted
that people often try to address the problems facing
coral reefs today without understanding the history of
the problem. 'Doctors would be sued for malpractice if
they diagnosed patients the way many scientists are
diagnosing oceans,' said Jackson, referring to the
practice of trying to solve ocean problems using current
data alone.

PROTECT NOW, SNORKEL LATER '

If we can get something in place in the next ten years,
we can bring many of these fish stocks back. Fish stocks
have a great capacity for resiliency. All is not lost,'
said Pandolfi. Pandolfi is not calling for the
restoration of all the world's reefs to their pristine,
unaltered state, he said. Instead, he hopes his data
will call attention to the critical situation facing
coral reefs. 'We need massive coordination at every
level from grassroots movements to governments to
international non- governmental organizations,' said
Pandolfi. 'For example, if the Honduran government bans
fishing in part of a reef, what is going to prevent
Hondurans from crossing the invisible border and fishing
on the Nicaraguan side of the reef? There has to be
coordination so that a country that tries to implement a
reef protection plan is not placed at a disadvantage in
relation to its neighbours,' Pandolfi explained.
Pandolfi noted that the new timeline of coral reef
destruction helped the scientists formulate reef
management recommendations. Among the recommendations
are reef preserves called 'no-take areas,' international
coordination, and reef restoration. These historical
analyses provide a baseline that doesn't shift and it
helps to put the current crises into perspective, said
Pandolfi. 'We are a fundamentally a historical culture.
By ignoring history we can not solve the problems that
we think we understand by looking at the present,' said
Jackson.

(c) 2003 by the American Association for the Advancement of Science