Algae chokes Costa Rican reefs

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A coral reef off the coast of Costa Rica is being suffocated by algae.

The reefs of Culebra Bay, in the Gulf of Papagayo, have been plagued by the invasive algae Caulerpa sertularioides.

Scientists at the University of Costa Rica are currently considering the best course of action in dealing with the algae, which is spreading fast over the reef.

Caulerpa serularioides is spreading quickly and it is currently estimated that 80% of the 2.4-kilometer-long reef has been covered.

Only a small fragment of this resilient algae is required to start a new colony, and these fragments can easily become dislodged by strong current, or the movement of a diver.

This means that manual removal would be difficult without spreading the problem further.

Ecological disaster"If you pull it up it will reproduce faster," Jenny Asch, who is co-ordinating the governments marine conservation program, told Reuters. The Costa Rican scientists therefore have to look for alternative options to eradicate the problem.

Caulerpa taxifolia, a similar strain of algae from the Mediterranean, has in the past been treated using solid chlorine blocks " however it is not yet known if this technique would be effective against Caulerpa sertularioides.

Despite its large scale, the problem has only recently been highlighted by the Costa Rican government.

The non-profit MarViva Association were the first to alert the government of the algae that threatens one of its most prized tourist assets. Cindy Fernandez, a marine biologist with the organisation, described the situation as an ecological disaster.

Ironically, it is the rapid growth of tourism in the area that is believed to be fuelling the algae growth. Inadequate sewage treatment facilities, and an increase in the use of fertilisers on hotel golf courses, have been identified as potential culprits.