The Philippines is often considered the world epicentre of marine biodiversity with approximately 200 species of shark and ray thought to inhabit its waters. However, data on the current status of shark and ray populations in the Philippines is notoriously scant, which is of concern when implementing effective management strategies, especially for species at risk of exploitation. Sharks and rays are experiencing large scale declines worldwide and creating baseline information on remaining populations is crucial in helping to develop the appropriate management tools to aid in their conservation.
In 2015, LAMAVE began working with the Tubbataha Management Office to assess the diversity and abundance of sharks and rays in Tubbataha Reefs Natural Park. The teams initial research focused on using Baited Remote Underwater Visual Systems (BRUVS) to gather baseline information on the presence of sharks and rays. In 2016 the BRUVS project expanded into a nationwide shark and ray assessment, and LAMAVE partnered with the Global Fin Print Project as part of an international effort to assess the current status of elasmobranchs in reef sites worldwide.
Another focus area of our research is to understand how sharks are using protected areas, and the movements they make within and outside park boundaries. To do this we are using various tags (satellite, acoustic) to track and monitor individuals.
BRUVS are unique camera systems, which are baited and left to record at various depths. When played back the footage can be used to identify species and abundance of sharks and rays; it is a research technique that can assess the effectiveness of Marine Protected Areas (MPAs) for elsamobranchs. Aside from our initial work in Tubbataha Reefs Natural Park, key study sites include Apo Reef National Park and the municipality of Cagayancillio, which was recently declared the largest MPA in the Philippines. More recently our team has been supporting Apo Reef Natural Park and GIZ with the use of Stereo BRUVS to assess shark biomass in this protected area.
Diver-based Underwater Visual Surveys (UVS), particularly transect-based surveys, are key tools in the study of fish ecology and have been applied directly to estimating absolute density of reef sharks. This technique has been employed by our research team in collaboration with the Tubbataha Management Office to assess abundance and trends in population presence and distributions in Tubbataha Reefs Natural Park.
In 2015 in collaboration with the Tubbataha Management Office and the Marine Megafauna Foundation the team tagged a number of whale sharks encountered within the boundaries of the park. One of the key questions was to understand where the sharks were going, and in particular, if they were travelling West moving outside of Philippine waters and into unprotected waters.
Acoustic tags can be used to study the activity patterns of sharks and rays, providing invaluable insights into the short term movements, site fidelity and reef connectivity of these animals. The tags which are fitted to the animal, interact with acoustic receivers that are positioned around the park. The project is a long-term study that is ongoing, with new tags and receivers deployed every year, with a focus on tiger, grey reef sharks and reef mantas. The project would not be possible without: James Cook University, University of Victoria, Marine Megafauna Foundation, Southern Shark Ecology Group, private individuals and of course the Tubbataha Management Office.
Baited Remote Underwater Visual Surveys
Baited Remote Underwater Visual Surveys
Baited Remote Underwater Video System (BRUVS) is a relatively novel, non-invasive survey technique that is increasingly being used to assess marine and aquatic ecosystems throughout the world. The survey method offers a unique insight into understanding the abundance, biodiversity and behaviour of shark and ray species in a multitude of habitats.
LAMAVE first began using BRUVS in 2015, as a baseline research technique to assess the diversity and abundance of sharks and rays in Tubbataha Reefs Natural Park. In 2016 we partnered with the Global Fin Print Project as part of an international effort to assess the current status of elasmobranchs in reef sites worldwide.
The main focus areas for BRUV surveys are Apo Reef Natural Park and the island municipality of Cagayancillio. Initial surveys were also conducted in Tubbataha Reefs Natural Park.
Assessing shark and ray abundance and diversity. Baited Remote Underwater Visual Surveys were first conducted in 2015 in collaboration with the Tubbataha Management Office. The systems alone helped identify the presence of 15 species of sharks and rays within the waters of the park - data that helped bring the total confirmed species of the park to 23.
Apo Reef Natural Park contains the largest contiguous reef system in the Philippines and is the second largest Marine Protected Area after Tubbataha Reefs Natural Park. In 2016 with the assistance of the rangers our team conducted the first assessment of marine megafauna including sharks, rays, whales, dolphins and turtles in Apo Reef Natural Park.
Cagaynacillio is an archipelagic municipality of Palawan, located in the Sulu Sea. Within the municipality, around 130km form the main island, is Tubbataha Reefs Natural Park, the most successful Marine Protected Area (MPA) in the country. In 2016 initial BRUV surveys by LAMAVE indicated moderate populations of both reef and pelagic species of sharks and rays. The current focus is assisting and supporting the local community in determining the viability of establishing a dedicated ‘shark sanctuary’, which will allow the residents of Cagayancillo to successfully manage their marine resources in a sustainable manner.
Check out some of the species our team have encountered using BRUVS across the Philippines.
Since 2015 LAMAVE and the Tubbataha Management Office (TMO) have been monitoring the shark and ray species of Tubbataha Reefs Natural Park (TRNP). Research focuses on shark abundance, diversity and movement. In 2016 the team tagged the first tiger shark in the coral triangle, while on-going research focuses on building the countries largest acoustic network to tag and study reef mantas, grey reef sharks and tiger sharks.
Tubbataha Reefs Natural Park is a 97,030-hectare Marine Protected Area (MPA) in Palawan, the westernmost Philippine province. Located at the heart of the Coral Triangle, the global centre of marine biodiversity, it was declared a UNESCO World Heritage Site in 1993. The park is managed by the Tubbataha Management Office (TMO) and LAMAVE have been working with their researchers since 2015 with the shared goal of understanding how sharks and rays use the protected waters of the park. The park is strictly off-limits to fishing which has made it the ultimate place in the Philippines to encounter reef sharks. It is also one of very few places in the country where divers can encounter tiger sharks, hammerhead sharks, and a host of ray species, making it one of the last refuges for sharks and rays in the coral triangle. The findings from the study will be crucial for understanding how these top predators use this protected area and will provide managers and policy-makers with key information on how to effectively manage these species, contributing to national planning to conserve sharks nationwide.
Baited Remote Underwater Visual Surveys were first conducted in 2015 in collaboration with TMO and the rangers of Tubbataha Reefs. These specially designed structures, consist of a camera and bait which attracts sharks and/or rays to the front of the camera. The footage collected has enabled us to confirm the presence of 23 species in the park.
Citizen Science, can be simply defined as ‘any individual who contributes their time or effort to enhance scientific knowledge’. In this case it’s the sharing of pictures and videos (data) of sharks and rays encountered by the diving community visiting Tubbataha Reefs. This campaign by LAMAVE and TMO has helped confirmed the presence of 23 known shark and ray species within Tubbataha Reefs Natural Park whilst also identifying individual whale sharks and manta rays (both Manta alfredi and M.birostris).
To understand how important the park is to sharks and rays, we need to understand their movements - how they use the park, identify key habitats and crucially, discover if some species are leaving the protected waters of the park by venturing outside the boundaries of the TRNP.
Acoustic tags allow us to assess local movements, site fidelity and residency. These tags, which can last between 3 and 10 years are carefully attached to the shark or ray. Once attached, the tags can communicate with acoustic receivers stationed around the park. Each time a tagged animal swims by, the receiver picks up their unique signal or 'ping', allowing us to map out their presence within the park. Satellite tags on the other hand, allow us to track animal movements beyond the boundary of TRNP as their signal is not reliant on interacting with an underwater receiver - instead, these tags transmit to passing satellites when the animal is at the surface.
The annual research expedition, which has been nicknamed “Expedition Shark” is a collaboration between LAMAVE and TMO. In 2015, the first expedition focused on tagging whale sharks in order to track their movements in the region; in 2016 the team fitted the first tiger shark in the Coral Triangle with a satellite tag, as well as tagging four grey reef sharks with acoustic tags. In 2017, another tiger shark was tagged with both an acoustic and satellite tag and a further five grey reef sharks and two reef mantas were fitted with acoustic tags. The next step will be to expand the acoustic network by deploying receivers in the waters of Cagayancillo, an archipelagic municipality located around 130km northeast of the Tubbataha Reefs Natural Park. The position of the receivers at Cagayancillo will shed light on short and long term habitat use of these animals and provide essential information for WWF-Philippines and the LGU of Cagayancillo to design new shark sanctuaries. Whilst it is only the beginning, this research is the Philippines’ most significant shark study to date.