CORAL REEF ASSESSMENT

Nursery site and biodiversity assessment

Introduction Objectives

Indonesia's coral reefs are the most biodiverse marine ecosystem on the planet and human dependance on their services is high However coral reefs are under relentless stress from a myriad of direct and indirect anthropogenic pressures. Coral Reefs are also a sensitive indicator of coral reef health, climate change, and rising ocean acidification. 50% of our reefs have collapsed, with 14% in the last decade. It is projected that coral reefs could disappear within in the next 30 years (Obura et al. 2019)

Monitoring coral reefs status and trends over time is essential to track ecological changes in the ocean and to inform management strategies and policy.

By combining standardized ecological monitoring programs we are able to build a comprehensive understanding of ecosystem functions and capacity over time.

Through our assessment we are monitoring coral coverage and composition, macroalgae canopy cover, disease and bleaching events. Combined with our roving survey data we can quantify fish diversity and abundance with tangible steps to track capacity building.

This data is used in our in-house data analysis and publication and as supportive metadata for independent research projects.

Methodology

Led by trained research divers, a minimum group of 2 interns conduct survey dives in a predetermined area on established dive sites within and outside marine protected areas. 1 diver manages the structure and the other tracks time and navigation

Equipped with a camera mounted on a 50x50cm quadrat, the structure is swam no more than 1 metre above the ocean floor capturing high resolution time lapse photos every 2 seconds. Due to complications with strong current, data is recorded based on time swimming and not on distance. Swimming is constant through the survey with a swimming to pause ratio timed by the buddy diver. One survey takes 11 minutes to complete.

The survey is replicated at a depth of 20m, 15m, and 10m and conducted twice annually at each recorded dive site in the region.

Once back on shore the photos are filed and put through a software that analyzes benthic type and coverage using a randomized dot method. The results are recorded in the Indo Ocean Project internal database. The photos are stitched together to generate a high resolution map of sections of reef and are compared over time.