Scientists are on the hunt for undiscovered phenomenon inside a 425-foot-deep “blue hole” off the Florida coast. Little is known about such holes, which are similar to sink holes on land and are “scattered across Florida’s Gulf continental shelf” but very difficult to access, according to the National Oceanic and Atmospheric Administration. What is known is that they’re incredibly diverse biologically, containing species from corals to sharks. A 2019 search of a 350-foot-deep blue hole known as “Amberjack Hole,” some 30 miles off Sarasota, found an “oasis in an otherwise barren seafloor,” including two dead smalltooth sawfish, an endangered species, the NOAA says. Now scientists will explore this deeper blue hole, which sits 155 feet below the surface of Florida’s Gulf Coast, over the course of a year, reports ABC News.
The expedition at the blue hole dubbed “Green Banana” kicks off in August and involves scientists from Mote Marine Laboratory, Florida Atlantic University, Georgia Institute of Technology and the US Geological Society. In addition to searching for various life forms, scientists are interested in learning whether the hole is connected to Florida’s groundwater. “The seawater chemistry in the holes is unique and appears to interact with groundwater,” the NOAA says. Divers will descend to the mouth and take samples using a “benthic lander”—a 600-pound, three-legged structure to which scientific instruments are mounted, per Popular Mechanics. The NOAA says the hole’s hourglass shape will pose a challenge to sampling. (The deepest known blue hole could nearly swallow the Eiffel Tower.)