Florida's Coral Reef has been in decline for 75 years.
The state’s waters house the third-largest barrier reef system in the world, but has lost more than 90% of its live coral over the years because of over-fishing, disease, algae, and climate stress.
"Increasing CO2 in our atmosphere has led to increased incidence and magnitude of things like heat waves, hurricanes,” said Jason Spadaro, program manager for coral reef restoration research at Mote Marine Laboratory.
“And … increasing the degradation of our coastal water quality, we've really opened up a lot of real estate and facilitated the biology of algae seaweed.”
The algae are much more competitive under the current conditions, he said, than corals are for space on the reef.
Crabs gobbling up nuisance algae
As part of an effort to restore the massive underwater ecosystem, researchers started the first hatchery of its kind for Caribbean king crab in Sarasota.
The crustaceans are being released onto the coral reef because they eat algae which would otherwise block needed sunlight.
"It eats algae that are chemically defended or calcified, so things that other herbivores avoid, and thus those algae become very difficult to control on the reef,” he said.
"A lot of our laboratory studies and some of our earlier translocation studies with wild crabs were very promising, dropping the algae cover on reefs by 50% to 80%."
Also read: Baby corals take first steps to getting back on the Florida Reef
Removing overgrown algae will give the corals space to grow and settle.
The first wave of king crabs was released over the weekend onto the reef in the lower keys.
Mote plans to deploy more crabs later this month.
The hatchery has more than 300 adult crabs and a long-term goal of producing up to 250,000 juvenile crabs annually.
Why care about Florida’s Coral Reef?
Florida's coral reef is by far the most valuable natural resource in the state and arguably beyond, Spadaro said, because it supplies our economy through various business engines like tourism, recreational fishing, commercial fisheries, and scuba diving.
We can also credit the reefs with storm protection.
“We have that biogenic structure out there, just off the coast that breaks up wave energy before it can make it to land. So, it is our first and best backstop against things like storm surge and hurricanes. Losing that that natural resource would be ruinous for the local economy,” Spadaro said.
Also read: Saving Florida's coral reef onboard 'The Ark'
Then there’s the biological diversity, of which it offers more than just about any other marine habitat in the U.S.
“Losing that biodiversity could lose the future cure to cancer. Could lose a species that occurs nowhere else that we haven't documented yet. Could absolutely change the hydrology and the weather and the local fisheries production.”
Past restoration efforts are working
There is promising evidence that science is prevailing some when it comes to Florida coral restoration.
Although efforts were set back by heat waves the last few years, especially for branching coral like endangered staghorn and Elkhorn corals, Spadaro said the massive-form corals like boulder brain and star corals are doing well.
The bigger ones tend to be slow-growing while being major reef builders.
“We actually did a big survey right after the heat wave, and found that 75% of those corals that Mote has out planted over the last 15 years, survived the heat wave and are actually growing, and many of them are still reproducing,” he said.
“There is some hope. But we don't need hope. We've got science telling us that what we're doing with some of these restoration interventions is working.”
