"This is uncharted territory," says Harbor Branch marine ecologist Brian Lapointe, "no one has ever had the chance to study the impacts of natural phenomena like hurricanes on reefs under siege from these harmful algal blooms that we believe are triggered by humans."
For three decades now, Lapointe
has been studying the harmful spread of macroalgae, or seaweed, on coral reefs throughout Florida and around the world.Besides smothering and killing coral itself, such harmful algal blooms (HABs) cover the food on which many fish rely, forcing them and their predators away, and HABs can fill ledges and crannies that attract lobster.
Ongoing funding from the Environmental Protection Agency
that began in 2003 had allowed Lapointe
team to study two isolated reefs off Palm Beach County that had become almost completely covered in lawns of an invasive, exotic alga called Caulerpa brachypus, among other species.This insidious alien is closely related to Caulerpa taxifolia, which has caused billions of dollars in damage since accidental introduction to the Mediterranean in 1989.South Florida dive operators have reported for years that overgrowth was so bad at some previously popular dive reefs that these locations were no longer worth visiting. Lapointe
believes based on past research that the spread of C. brachypus and other macroalgae species, in Florida and elsewhere, is largely driven by nutrient pollution from land-based sources.
says that while the removal of macroalgae may be a welcome event for reefs, the reprieve is not likely to last.Small fragments of C. brachypus, for instance, have already been spotted and blooms could re-emerge as the environmental conditions that have fostered its spread and that of other troublesome species have not changed.
"This is a break, not a solution for the reefs," says Lapointe
of the hurricanes' inadvertent macroalgae cleaning.
As buried and scoured reefs begin to recover, macroalgae problems could become even more pronounced, says Lapointe
.Previous HABs have proceeded in competition with healthy reef populations.Now, scoured reefs have become nearly blank slates.
Additional information about Dr. Lapointe's
research, including background material on macroalgae species, chemical signature studies, and pollution sources, as well as video of reefs before and after overgrowth, go to: http://www.hboi.edu/marinesci/dynamics.html
...As the massive $8 billion Everglades restoration project increases the amount of water flowing into the bay, nitrogen in that water may kill coral, said Dr. Brian Lapointe, a scientist at the Harbor Branch Oceanographic Institution in Fort Pierce.
The restoration is designed to clean up water passing through the region, and return some of the historic water flow to the Florida Bay.Though the project will filter pollutants from the water, the focus is largely on phosphorus, which scientists say poses the most serious threat to the Everglades.
said nitrogen, which comes from farm runoff, sewage and other places, is another culprit.Nitrogen feeds algae, causing it to burgeon and compete with coral, he
said.That type of plant growth also clouds up the clear water that corals prefer.He
said there have already been examples of this phenomenon in the Keys.
Between 1996 and 1999, after an increase in the flow of water into the bay, 38 percent of the living coral in the Keys died off, a problem Lapointe credited to "nitrogen overloading."Other pollutants were clearly in that water, but Lapointe
said nitrogen caused an explosion in algae blooms, which led to the reef's demise.
The Keys reefs began to recover when officials decreased the water flow into the region in 1998, Lapointe
But as the amount of water flowing into the bay increases through the Everglades restoration, so will the amount of nitrogen reaching the area, and Lapointe
said the reefs will again be in danger.