This was our first time to use BRUVs (baited remote underwater video), so doing the type of fieldwork required for this method presented new challenges for us. Some of these challenges are probably trivial to others working outside of the developing world. For example, prior to the study, we had to revive and recondition an old and leaky rubberboat and outboard engine that had been decommissioned for more than a decade. No other platform that had enough manoeuvrability space to carry all the equipment was available to us. However, our resurrected rubberboat was not equipped with a capstan winch or anything that could make hauling up the BRUVs easier. Fortunately, we had a great team of volunteers who were game enough to provide much needed elbow grease!
The highlight of the fieldtrip was the moment we discovered that a school of hammerhead sharks were recorded in one of our BRUV deployments. This was a remarkable discovery because sharks are rarely seen in Apo Island. In fact, divers very rarely encounter sharks in Philippine waters most probably because of overfishing. Before we left Apo Island, we showed the video of hammerhead sharks to members of the local community during an informal gathering. Many of the locals were amazed by, and took pride in, our discovery. Further analysis of our video data revealed that we actually recorded the hammerheads in the same general area twice. We also found that we recorded solitary hammerhead and thresher sharks in a few deployments.
Hard to say because the entire Apo Island is a very interesting and exciting place in terms of its marine biodiversity and management history. It is one of Asia’s top dive destinations and the so-called “poster child” of local marine resource management in the Philippines The opportunity to study fish and benthic communities beyond the usual limits of scientific scuba diving, especially within the typhoon-impacted reserve, made Apo Island more special for us.
This work would not have been succesful without the support of the members of the protected area management board of Apo Island. Barangay captain (village chief) Liberty Pascobello-Rhodes deserves special mention here because she made sure that we had everything that we needed while we were working at Apo. Monet Raymundo, Ryan Murray, Moonyeen Alava, Jasper Maypa, Zacharias Generoso, Ruben Alaton and Sidney Mendes greatly contributed to the success of this study in various ways.
The entire study was an important learning experience for the Filipino team members because we were introduced by our Australian colleagues to a technologically-advanced but cost-effective approach to study mesophotic coral ecosystems. This collaboration also helped encourage other marine scientific research groups in the Philippines to use BRUVs and video analysis software to study mesophotic coral ecosystems in other locations. In short, our work pioneered the use of BRUVs in the Philippines.
Recently, we expanded sampling to include two other locations on the mainland island of Negros, about 11 to 25 km away from Apo Island. These locations, apart from being more exposed to anthropogenic stressors (e.g. fishing, siltation and coastal development), are situated on two parts of the Negros coast that appear to have different geological characteristics (well-developed versus patchy reefs). The general objective of this expansion is to begin to understand how reef development and fish community structure vary with depth in this geologically-complex region of the world’s epicentre of marine biodiversity.
Benthic habitat and fish assemblage structure from shallow to mesophotic depths in a storm-impacted marine protected area | article
Abesamis RA, Langlois T, Birt M, Thillainath E, Bucol AA, Arceo HO, Russ GR (2018)
Coral Reefs 37:81-97