`Killer algae' back, scientists discover

The "killer" is back.

Caulerpa brachypus, an exotic, highly invasive underwater vine known as "killer algae," has spread north to take over many deep Martin County coral reefs, scientists studying the algae said Wednesday.

The algae, which have been missing from Palm Beach County reefs since the 2004 hurricanes, have a reputation for smothering coral and forcing sea life to avoid normally thriving ecosystems.

Now scientists at Harbor Branch Oceanographic Institution have documented a resurgence -- this time covering local reefs more than ever.

"It's coming back with a vengeance," said Brian LaPointe, a Harbor Branch scientist. "This is the first time we've seen those reefs in Martin County covered with that much Caulerpa brachypus."

LaPointe and other scientists found the algae growing in the Indian River Lagoon in 2003, and at that time he feared the fast-spreading plants would take over that diverse environment like it did deep-sea corals.

But scientists discovered the pollution-loving algae could not tolerate bright conditions, so it thrived only in shady, deep coral reefs.

Plus, the lagoon algae and the blooms on Palm Beach and Martin county reefs were blown away with the winds from Hurricanes Frances and Jeanne in 2004 and Wilma in 2005.

But monitoring last summer, LaPointe and research assistant Chip Baumberger found the algae blooming in about 65 to 80 feet of water about halfway between the Jupiter and St. Lucie inlets, on a natural reef known locally as the "Loran Tower Ledge."

The algae also were spotted in small patches in the Indian River Lagoon and in 45 to 55 feet of water on other Martin County reefs.

It was also seen as far south as Deerfield Beach, LaPointe said. "We felt strongly it would come back," he said. "It was only a matter of time."