3 Jun 2015

American Samoans to look out for coral bleaching

1:19 pm on 3 June 2015

American Samoa Department of Marine and Wildlife Resources says it wants the community to report signs of bleaching and other damage effecting coral reefs.

The department's director, Ruth Matagi-Tofiga, says residents have seen a lot of 'white' on the reefs and this is due to the high sea temperatures from January to May this year.

She says coral is a unique animal that can only survive with the presence of a tiny algae that lives inside the coral and provides food for it to grow.

Dr Ruth Matagi-Tofiga says coral bleaching occurs when this relationship is strained, primarily due to rising sea temperatures.

The heat stress causes the coral to expel the algae, making it very difficult for the coral to receive enough nutrition.

Other stressors are sedimentation, pollutants, and change in salinity.

She says the death of local corals affect the functioning of the reefs including fish populations, which rely on the corals for shelter and food.

American Samoa Vatia Village

American Samoa Photo: TORSTEN BLACKWOOD / AFP

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