Coral reefs damaged : What’s the big deal?

Coral reefs damaged : What’s the big deal?

Context- Coral reefs are essentially just big limestone structures built by thousands of tiny coral creatures called polyps. They’re found in more than 100 countries, and just like pina coladas, they belong in tropical areas. But they’re not looking too healthy.

(Credits- Geographical Magazine)

Increased ocean temperature caused by climate change is the main cause of coral bleaching events. That’s when reefs expel the symbiotic algae responsible for their color. If that happens over longer periods, the corals can eventually die.

The planet has already lost about half of its shallow water corals in in the past three decades. And at the current rate, up to 90% of them will disappear by the middle of the century.

What are reefs good for?

  • Some 200 million people around the world depend on reefs to protect their coastal communities from storm surges and waves. Many of those people live in the US.
  • Coral reefs act like low-crested breakwaters and absorb 97% of wave energy. This substantially reduces coastal flooding and erosion.
  • According to the United States Geological Survey, reefs help avert $1.8 billion in damage each year in areas like Florida, Hawaii and Puerto Rico. And if those reefs lose just 1 meter in height, $5 billion in property and economic damage is at risk.
  • With coastal flooding predicted to worsen this century, reefs will play an even more important role.

What else do reefs do then?

  • Coral reefs cover less than 0.5% of the earth’s surface, but they are home to about 25% of all marine species. Kind of like the rainforests of the sea. But without the snakes. Well, there might be some snakes.
  • With biodiversity, more is better. It provides planetary resilience, a vast resource of potential scientific discoveries, and is the result of millions of years of evolution. Biodiversity underpins a healthy planet and social well-being.
  • Almost everything we know about coral reefs is based on those close to our shores, but most of them are distant, biodiversity hotspots in otherwise barren ocean basins, where they act as food bowls, rest stops, and even navigation waypoints for critters on the go. This diversity is a treasure of incalculable value.

Why does that matter?

  • A huge number of modern medicine’s drugs are derived from natural sources. And so far, most of those have come from land organisms.
  • But given 80% of life is under water, researchers are increasingly looking to marine organisms to satisfy the need for novel chemicals and enzymes to build the pharmaceuticals of tomorrow.
  • Some estimates say the prospects of discovering a new drug in the sea, particularly in coral reefs, is hundreds of times more likely than finding one on land.
  • The anticancer agent Ara-C, included on the World Health Organization’s List of Essential Medicines, is found in sea sponges on a Caribbean reef.
  • Dolastatin 10, found in sea hare, which is being tested as a treatment for breast and liver cancers, tumors, and leukemia.
  • One promising molecule, eleutherobin, that is believed to slow cancer cell growth is found in a common species of soft coral. Scientists have been able to use its genetic code to figure out how they might soon be able to manufacture the chemical in large quantities.
  • Humans eat about 150 million tons of seafood a year and these fish have to breed somewhere. Coral reefs provide shelter and function as nursery grounds for some pretty commercially important fish, like grouper and snapper, as well as invertebrates like the lobster.
  • Some studies put the value of coral reef fisheries at $6.8 billion a year globally. About one billion people source their food or income directly from reefs.

And if they’re not managed well?

  • Potential food shortages could be the consequence. Especially when combined with failing crops from climate change. A study of reef damage in Kenya revealed drastic declines in key fish catches after a combination of factors in 1998 warmed the ocean by between 1-2 degrees Celsius.
  • That’s not to mention the possibility of increased mass migration, as people try to avoid famine and flooding.

Way Forward- Local restoration efforts by transplanting coral, the establishment of marine protection areas which work like national parks, and stopping run-off from agricultural and effluence. In the long term, reducing emissions will give coral reefs survive.

Source- Indian Express

NEWS- Coral reefs damaged : What’s the big deal?

Syllabus- GS-3; Environment