Up to one third of the Island?s vital seagrass fields have been lost since 1997 the Bermuda Biodiversity Project has found, scientists and government conservationists were told yesterday.

Assistant Professor of Biology at Florida International University, James Fourqurean in the opening lecture yesterday at the five-day ?Seagrass Biology, Ecology and Management? course being sponsored by the Department of Conservation Services, said: ??One third of the seagrass beds were gone or in very, very serious decline. I?d be very concerned if I were you.?

Dr. Fourqurean said the most common seagrass in Bermuda is Thalassia testudinum, or Turtle Grass which is naturally able to break down nitrogen-phosphate in sewage into atmospheric nitrogen. In 1997 there was 5,100 acres of seagrass on the Bermuda seamount, according to the Bermuda Biodiversity Project but by last year, only 4,000 acres was found.

Environment Minister Neletha Butterfield told the course: ?The Ministry intends to designate significant seagrass meadows as critical marine habitats under the Protected Species Act. Further, the dredging of seagrass beds will not be permitted, and fines will be increased for illegal dredging activities.?

She added ?environmentally safe moorings that are less damaging to seagrass beds? would be actively promoted. During the (coming) legislative session, the National Parks Act will be amended to include seagrasses as part of Bermuda marine parks system,? she said.

Dr. Fourqurean said seagrass is a very slow-growing plant, with scientists estimating it can take seagrass 15 to 20 years to grow over a scar a foot across.

?New tourist beaches want to actually remove the grass in front of their beach because tourists don?t like walking on it,? he said. ?This is silly because the beach will erode faster.?

The dollar value of maintaining the aesthetic quality and erosion control of Bermuda was priceless, he said.

?What we think of as natural is what we remember it to be like when we went into the sea as children,? he said. ?But no one here is old enough to have seen the original state. There is a demonstrable economic impact from the loss of seagrass.?

Another reason could be the increase in seawater temperature due to a multi-decade oscillation throughout the Atlantic, he said. ?Other than digging it up to make ship channels, another reason for the decline is, nutrient loading,? he said. ?All the food we import on ships end up on the seagrass beds as nitrogen and phosphorous.?

The more sewage seeps into the sea from the Island?s cesspits, or is pumped in from local pipelines, the greater the concentration of these chemicals in the ocean, he said.

As the grass die and it is replaced by micro-algae and phytoplankton, who thrive in sewage rich water. These microscopic plants block out sunlight, killing other species of ocean plants.

But as most of the lost seagrass has disappeared from off-shore sites but in the more ?pristine? sites, the devastation was probably not caused by nutrient loading, he said, but perhaps by an increase in Bermuda?s turtle population. Seagrass beds are bio-diversity hotspots as they are not only habitats for conch and sea urchins but are also nurseries for black rockfish and spiny lobster, he said.

?Many plant eating fish shelter at the coral reefs during the day and go out to the grass beds at night to feed,? he said.

The loss in fishery value lost every year because of declining seagrass beds is estimated at $30,000 per year, he said.

Most of the biomass of seagrass lies under the seafloor in long ?runner shoots? that can spread up to six kilometres across, he said.

?These shoots keep the sand from moving around and have a positive effect on water quality,? he said.

Damage to seagrass beds includes propeller scars and mooring chains.