While bleaching is a naturally occurring event that can be overcome, multiple and extreme bleaching events will be a death sentence for coral reefs. Photo: Wikimedia Commons
Coral reefs off Florida’s coastline are in middle of a massive bleaching event. If you’ve followed the news and have a cursory understanding of how coral bleaching happens, this might not come as a surprise. What is surprising, however, is the sheer scale of it. According to reports, “a monitoring site in the Florida Keys has recorded 100 percent coral bleaching since late July.”
In July, buoys in Manatee Bay in Florida’s Middle Keys recorded water temperatures so high that initially researchers assumed it was a mistake. Sadly, though, it was not an error. The water hit hot tub temperatures, measuring 101 degrees°F, which is not good for anything living in them. In very simple terms, corals bleach when they are stressed, and hot tub temps stress them out. While bleaching is not necessarily a death sentence for corals, repeated and extreme ones can be.
“When corals are stressed by changes in conditions such as temperature, light, or nutrients,” NOAA explains, “they expel the symbiotic algae living in their tissues, causing them to turn completely white.”
While the Florida bleaching event is worrisome on its own, it appears that a global mass bleaching event is currently happening.
“This is a very serious event,” Derek Manzello, the coordinator of the National Oceanic and Atmospheric Administration’s Coral Reef Watch Program, said on a conference call with reporters Thursday. Florida’s corals are an extreme example, but they are an indicator of what could be in store for us.
Coral reefs are extraordinarily important parts of the ecosystem, but they’re also a huge part of Florida’s economy. Ian Enochs, who works as a research ecologist a NOAA’s Atlantic Oceanographic and Meteorological Laboratory told reporters that they pump somewhere between $678.8 million and $1.3 billion worth of economic benefit to Florida.
That includes some $577.5 million in recreational diving and snorkeling, and $31.2 million in commercial fishing. Not only that, but reefs provide a barrier between raw ocean power and our shorelines. As climate change exacerbates storms world wide, those barriers are becoming more and more important.
“Reefs are also really important for buffering storm energy and hurricane wave action that would otherwise pummel our shorelines and our coastal infrastructure,” Enochs said. “They are living walls that breaks that energy from hitting hitting our shores.”
Just to reiterate how important reefs are for the general health of the entire planet, about 1/4 of all marine life uses coral reefs for something important over the course of their lives. Whether its food or shelter, without them, many species are going to run into trouble in the future. And Florida looks to be be just the tip of the iceberg. Reefs from Columbia to Cuba are showing signs of serious heat stress, which, as I mentioned, can be deadly if repeat bleaching events occur. Since coral reefs have evolved to like water temperatures between 73 and 84 degrees Fahrenheit, as the waters warm year after year, those reefs are going to suffer. In the Florida Keys, water temperatures in July exceeded those levels for nearly the entire month.
“We hear the word unprecedented thrown around all the time, but allow me to qualify that word with the facts: Florida’s corals have never been exposed to this magnitude of heat stress. This heat occurred earlier than ever before,” Manzello said. “A big concern is that temperatures are reaching their seasonal peak right now, so this stress is likely to persist for at least the next month. These corals will experience heat stress that is not only higher than ever before, earlier than ever before, but for longer than ever before. This is key because the impacts to corals is a function of how high the heat stress is and how long it lasts.”
