The lure of shipwrecks
By Susan Cocking
March 09, 2008
scientists found a rich reef fish community thriving near three sunken freighters in 250-300 feet of water.
Anglers wouldn't have many bottom-fishing opportunities in the deep ocean waters off Broward County if there were no shipwrecks.
A three-year study by scientists at Nova Southeastern University Oceanographic Center revealed a rich reef fish community thriving around three freighters sunk in 250 to 300 feet of water -- compared with an almost barren natural rubble bottom nearby.
Researchers David Bryan and Kirk Kilfoyle used a miniature, camera-toting remote-control submarine, or ROV, operated by Steve Van Meter to count fish around the wrecks of the Bill Boyd, Papa's Reef and Caicos Express and on the adjacent ocean floor.
They found 615 fish of 42 species on the natural bottom, but nearly 51,400 fish of 65 species on the vessel reefs.
''We were the first to look at these wrecks with an ROV,'' Bryan said. ``We got to see things not many people have gotten to see. It was surprising we didn't find [nearly] anything on the natural bottom.''
Operating the VideoRay submersible with a joystick from the surface, the scientists found the wrecks were dominated by thousands of tiny, plankton-eating basses, which in turn provided forage for larger fish such as Almaco and amberjack, blackfin and gray snapper, and scamp grouper. The researchers also spotted some large Warsaw grouper and hogfish.
''We all wished we had a spear gun,'' joked Bryan.
Bryan and Kilfoyle concluded the deep shipwrecks do not appear to be attracting fish away from nearby natural habitat. Instead, they said, the fish congregating around the vessels are more similar to those found on the deep-water coral reefs of the Oculina Banks off Fort Pierce. Those reefs have high relief and are much more complex than the natural bottom off Broward County.
Said Nova marine biology professor Richard Spieler, who supervised the project: ``There's a strong possibility that the use of artificial habitat in deep water in places like Broward enhances the fishery.''
While the ships seem to increase reef fish productivity, the scientists said, they may also attract larger groupers that are typically rare in Broward County, making them more susceptible to hook-and-line and spearfishing.
Said Spieler: ``Ships can serve a purpose. They would serve a great purpose if you could restrict fishing on them.''
The $100,000 study was funded by the Florida Fish and Wildlife Conservation Commission, Guy Harvey Research Institute, and NOAA Fisheries.