People from Mangalilu to Lelepa Landing area in North Efate have been warned not to swim in the sea or get sea food from the coastal sea waters in that area.
The Vanuatu Fisheries Department has issued the warning because of a Red Tide found in the area of Fatkao that is poisonous and unsafe on the skin.
Fisheries Department Deputy Director Sopert Gereva says, “People in the area must not eat any dead fish or shells found there because they are poisonous.”
Red tide is a common name for algal blooms, which are large concentrations of aquatic microorganisms, such as protozoans and unicellular algae. The upwelling of nutrients from the sea floor, often following massive storms, creates the conditions for the algae to multiply and triggers the bloom event.
The Deputy Director says the blooms can harm people’s skin, eyes and ears if they touch them and then touch their face so it is important not to get close to them.
Mr Gereva says people can still fish in deep waters in this area but not along the coastline or on the reefs. When there is low tide, the sediment can settle on surfaces like on the reefs, corals, stones and on sea shells and can kill marine life. And it is poisonous for people to eat the shells or fish in the area where the Red Tide occurs.
He says algae bloom doesn’t normally appear on the surface of the sea but with the North Efate case, the weather situation has caused it to come to the surface.
He says human activities have contributed to the Red Tide.
He says activities such as people dumping rubbish into rivers which then flows into the sea; people cutting down many trees, especially close to rivers; or feeding animals like pigs or cattle or putting up toilets close to the sea or a river.
This is because when it rains, these activities allow more waste or soil to be washed into the sea where it settles at the bottom of the ocean.
Sea currents then take the dirt up to the surface of the sea where it joins with the algae to create a Red Tide which quickly reacts to the air and becomes poisonous.
A local from Mangaliliu says at first the algae bloom problem in the area was small but then it spread to Lelepa Landing which is about five kilometres away.
Mr Gereva says the rapid spread of Red Tide happens because of a fast chemical reaction between the algae and another microorganism called Dinoflagellate which can swim very fast .
He says the tide can appear in different colours, it can be red, green, purple or other colours.
Some locals in nearby Sunae and Moso Island have reported they have also seen the Red Tide near their communities and a Fisheries Department team is currently investigating this.
Deputy Director Gereva says the Fisheries Department is unable to eliminate the Red Tide and it could stay in the area for some months if the conditions there are favourable to it and it gets more energy.
He says only wind can move a Red Tide away.
Some locals in North Efate told VBTC they are concerned and sad about the Red Tide as many people depend on sea food.
Deputy Director Gereva says while the alage is moving away from some areas he is strongly advising people not to gather food from the reefs or swim in the area “for some months”.
The Fisheries Department says oil spillage from ships does not contribute to the Red Tide.
“People should not be frightened of the situation,” he said.
“But they should not to go to the reefs to get food because it is not safe.”
People in other areas of North Efate can still go to the sea to get food or swim but the department is asking people to report any signs of the algae bloom that they see in the sea because it can spread very quickly.