Fish Biomass Assessment in Timor-Leste

In June 2018 we spent two weeks in Timor-Leste (East Timor) doing reef fish biomass assessments for the WorldFish NGO. This was a repeat of surveys we first carried out in December 2016. This project is designed to see whether fish biomass can be improved by encouraging local fishers to target more pelagic species by the use of FADs or Fish Attracting Devices. We made fish counts at three sites in each of four locations. No diving was possible at a fifth, south-coast, location because of rough weather and dirty water. 

The three locations around Atauro Island, 25 km offshore from Dili on the north coast of Timor, had clear water and good coral cover but the coral had been damaged by bleaching at Vemasse on the north coast of Timor itself. Most Acropora corals were dead at Vemasse although most other corals were still healthy. Fish populations were similar to those recorded in 2016 although a detailed comparison will have to wait until all the data is entered and analysed.

Coral reefs in Timor-Leste fall steeply into deep water. The 25 km wide channel between the mainland and Atauro Island is a staggering 5,000 metres deep! Strong currents sweep the reef and there is a rich growth of filter feeding invertebrates amongst the corals in the shallows and on the deep reef below about 25 metres depth. This is quite a contrast to the Great Barrier Reef where sponges, ascidians and other invertebrates are much less abundant.