From FLORIDA TODAY

   Commonly referred to as the "green tide" the algae, Caulerpa brachypus and related sea weed have been wreaking havoc on coral reefs in shallow waters. They form a green coat on coral reefs causing them to crumble under the weight. They also reduce oxygen for fishes. The algae is native to shallow Pacific estuaries and was spotted in May 2001 by HBOI researchers. It is believed to have been either introduced by ship ballast water or by emptying aquarium water into the sea. The algae typically thrive in shallow high nutrient waters in estuaries but they are able to survive in deep waters because they derive nutrients from stormwater outfalls, deep-injection wells and septic tank discharges. However, huge losses to the tourist industry are expected as a result of damaged coral reefs. The algae has been spreading north and southwards from the reefs in West Palm Beach since last year and is expected to grow 30 miles per year.

   A related seaweed Caulerpa verticillata also blankets coral reefs but isn't found in deep waters. In the late 1980s, the spread of invasive algae Caulerpa prolifera was controlled by the presence of sea slugs that fed on them. Scientists are now considering introducing a similar sea slug species to control the present distribution of invasive algae. But it is doubtful whether there will be enough sea slugs to handle the problem.