Red Tide Poses Lingering Threat To Marine Mammals

New research indicates that toxins produced during red tide outbreaks continue to pose a threat to marine mammals, even after the blooms have disappeared.

The toxins can accumulate in high concentration on seagrass, the principal food source for manatees, and may remain there after the bloom is gone. This can be especially dangerous when the red tides form in early spring and the migrating manatees move to coastal waters.

Scientists have long debated the involvement of red tide in dolphin mortalities, primarily because toxins were not always found in dead animals and because the source of the poisoning was not understood. The new research indicates that fish which eat plankton can feed on red tide cells, and toxins only appear to be fatal if they pass through their gills. Contamination of these fish can cause fatalities in other species including seabirds.

The 2004 spring mortality of 107 dolphins in the Florida Panhandle was the first evidence that brevetoxin-contaminated fish are a threat to dolphins. "It was very clear very early on that many of these dolphins had stomachs very full of undigested fish, which suggested that something killed them right away," said NŽlio Barros, manager of Mote Marine Laboratory's stranding investigations program. "Typically, when we find stranded or dead animals, their stomachs are nearly empty and they're usually emaciated."

The study, which included scientists from Florida Fish and Wildlife Conservation Commission's Fish and Wildlife Research Institute, University of North Carolina Wilmington Center for Marine Science, Mote Marine Laboratory, Harbor Branch Oceanographic Institution and the National Oceanic and Atmospheric Administration, also shows a need for further research.

"The finding that red tide is this toxic to manatees and dolphins highlights the need for more research on the health effects of red tide toxin exposure in human populations," said David Schwartz, M.D., director of the National Institute of Environmental Health Sciences.

Sound Off on Gulf Goals

A new website detailing priorities for restoration of the Gulf of Mexico has been launched so residents can provide feedback on ocean research, education and management recommendations developed by the Gulf of Mexico Alliance.

Five states bordering the Gulf and the federal government are working to coordinate initiatives that improve and protect water quality; restore coastal wetlands and estuarine ecosystems; reduce pollution and nutrient loading; identify and characterize Gulf habitats to support coastal management; and expand environmental education to improve stewardship.

To review and submit comments
visit www.gulfofmexicoalliance.org.

Little Salt Spring Yields Ancient Artifacts

Divers from the Florida Aquarium and the Rosenstiel School of Marine & Atmospheric Sciences at the University of Miami have unearthed two unique burial artifacts estimated to be approximately 8,000 years old - a green stone pendant and an artifact that appears to be part of a spear-thrower.

Located in North Port, Little Salt is a unique archeological treasure trove because the 240-foot deep, hourglass-shaped spring is fed from an underground source with no dissolved oxygen. Bacteria cannot grow, so wood and other organic materials do not decompose.

"Both artifacts come from disarticulated human burials on the east side of the basin in about 30 feet of water. This is an area where we had never done any exploration before," said John Gifford, associate professor of marine affairs and policy. "We were able to explore this area this year because of the extra volunteer divers we had from the Florida Aquarium in Tampa, who actually located these particular items." Because 95 percent of the sinkhole remains unexplored, many believe the most revealing lessons in history await discovery. The great abundance of artifacts and vertebrate, invertebrate, and plant fossils afford a unique opportunity to reconstruct the natural and cultural environment of Florida.

Setting Stage for Mangrove Recovery

A new publication available from Lewis Environmental Services hopes to change conventional thinking about mangrove restoration worldwide by detailing techniques to support natural recruitment of mangroves. "Whether in Tampa Bay or Hong Kong, mangroves will colonize if you establish the proper conditions," says ecologist Robin Lewis, author of "Ecological Engineering for Successful Management and Restoration of Mangrove Forests," published in July in the science journal, Ecological Engineering. Lewis describes the well-intentioned but often faulty and costly notion that restoration requires planting mangroves, when in fact the trees often recolonize on their own if conditions are right and mangrove propagules can float in.

Fishing Regs Online

Updated saltwater fishing regulations are now online at the Florida Fish and Wildlife Conservation Commission's website, including seasonal openings and closings for popular species such as red snapper, snook and crawfish. For more information, visit marinefisheries.org.

Tampa Bay is getting better
You can help

Buy a Tampa Bay Estuary tag and help keep Tampa Bay on the road to recovery. They're available year-round in your local tax collector's office or request a Tampa Bay Estuary tag with your annual renewal.

The cost is $27 for the first year and $17 after that - with $15 going directly to projects that benefit the estuary, including the publication of Bay Soundings.