It's past time to tell the truth about the state of the world's coral reefs, the nurseries of tropical coastal fish stocks. They have become zombie ecosystems, neither dead nor truly alive in any functional sense, and on a trajectory to collapse within a human generation. There will be remnants here and there, but the global coral reef ecosystem -- with its storehouse of biodiversity and fisheries supporting millions of the world's poor -- will cease to be. [...]
But by persisting in the false belief that coral reefs have a future, we grossly misallocate the funds needed to cope with the fallout from their collapse. Money isn't spent to study what to do after the reefs are gone -- on what sort of ecosystems will replace coral reefs and what opportunities there will be to nudge these into providing people with food and other useful ecosystem products and services. Nor is money spent to preserve some of the genetic resources of coral reefs by transferring them into systems that are not coral reefs. And money isn't spent to make the economic structural adjustment that communities and industries that depend on coral reefs urgently need. We have focused too much on the state of the reefs rather than the rate of the processes killing them. [...]
What we will be left with is an algal-dominated hard ocean bottom, as the remains of the limestone reefs slowly break up, with lots of microbial life soaking up the sun's energy by photosynthesis, few fish but lots of jellyfish grazing on the microbes. It will be slimy and look a lot like the ecosystems of the Precambrian era, which ended more than 500 million years ago and well before fish evolved.
Great news for jellyfish!