When news breaks, you need to understand what matters — and what to do about it. At Vox, our mission to help you make sense of the world has never been more vital. We rely on readers like you to fund our journalism. Will you support our work and become a Vox Member today? A baby bust threatens the future of an already struggling reef. Once a year, typically after sunset in the late summer, the coral baby-making process begins.
Large colonies of coral spawn, spewing out sperm and eggs, often in pea-size bundles, that drift around until they encounter the spawn of other corals. Fertilized eggs turn into coral larvae — tiny and squishy free-swimming organisms — which eventually settle on the seafloor.
There they metamorphose, like a caterpillar to a butterfly, into a coral polyp. Those polyps clone themselves over and over again, eventually forming larger coral colonies that build reefs. But in Florida, this process is broken. For at least a decade, and likely longer, researchers have barely found any new coral babies or juveniles of most hard corals during surveys in South Florida and the Florida Keys, home to the largest coral reef in the continental US.
While many of these corals are still spawning in the wild — the part where they release sperm and eggs — something is preventing that spawn from eventually growing into polyps, or babies, Winters, and other experts said. This is a serious problem for a long embattled reef. These threats have killed off most of the live hard coral in the Florida Keys. While corals can reproduce asexually — by cloning themselves — sexual reproduction is incredibly important because it introduces new genetic diversity that helps corals adapt to the increasingly hostile ocean conditions.
Rather, each step of the reproductive process has likely been compromised to some degree. Over the last few decades, coral reefs in Florida and across much of the Caribbean have lost an enormous amount of their large, adult coral colonies that can spawn.
