Survey looks for foreign marine species |16 May 2005

The study is being carried out by the World Conservation Union (IUCN), with help locally from the Seychelles Centre for Marine Research and Technology – Marine Parks Authority (SCMRT-MPA) and the Ministry of Environment and Natural Resources.

The spread of invasive marine species is thought to be “one of the four main threats to biodiversity in the world,” said Dr Ameer Abdulla, a marine specialist with the IUCN’s Global Marine Programme. “It’s not an issue to be taken lightly.”

Dr Abdulla said it was important, however, to differentiate between species that are introduced and cause virtually no harm, versus “invasive species” that can reproduce, establish viable populations and cause damage to the native ecology of an area.

The IUCN is hoping the survey will provide “a sense of what species are here” and which, if any, could be considered invasive, he added.

Early finds of the study have revealed two species of bryozoans – animals that closely resemble brown algae – that were probably introduced. But bryozoans are considered to be a “global species” and are not believed to cause much harm, said Dr Abdulla.

Seychelles was chosen as a pilot site for the study partly because of the presence of commercial shipping and the volume of recreational boats that frequent the islands.

The transfer of ballast water – which is used to balance large ships after they load or unload cargo – from port to port is thought to be one of the leading causes of the spread of marine invasive species worldwide, as well as from plants and animals that grow on the hulls of vessels.

The research team is surveying sites around Port Victoria and the adjacent Ste Anne Marine National Park, but they will also be diving in areas around Cousin and Cousine islands for a comparison.

“We’re hoping not to find any (invasive species),” Dr Abdulla said.

Once the field survey is completed later this month, the IUCN will be submitting a report with guidelines to deal with and perhaps even eradicate any potential invasive species. The report is also expected to propose measures to prevent their spread in the future.

Dr Abdulla said the guidelines should be completed by early 2006.

According to the SCMRT-MPA, the baseline survey will be used in the development of a three-year programme to undertake consistent monitoring of some sites around the Victoria harbour and high value coral reefs.

“This will provide SCMRT-MPA and the Ministry of Environment and Natural Resources with an easy and cost-effective tool to monitor the health of the reefs,” said a statement from the SCMRT-MPA.

The IUCN project is being funded by the oil conglomerate Total.

Seychelles’ own petroleum company, the parastatal Sepec, recently announced that it had ordered two new oil tankers each with an environmental facility that could change ballast water without spreading marine organisms.