An 8 day marine biological baseline survey was conducted by Vatuvara Foundation and the Wildlife Conservation Society (WCS) from 8-16 May, 2017. The expedition was the first systematic effort to document the marine environments of Kaibu, Yacata, Vatuvara, Kanacea and Adavaci islands in the Northern Lau Group.
Helen Sykes of Marine Ecology Consulting was contracted to be part of this team, and one of the report writers, as one of the foremost experts in marine ecology in Fiji.
The province of Lau, located in Fiji’s Eastern Division, comprises 60 islands and islets collectively known as the Lau Group. The Lau Group has been identified as an area of national significance and high priority for marine protection.
On 20 February 2016, Fiji was hit by Category 5 Tropical Cyclone Winston that caused widespread damage across the country. Cyclone Winston made first landfall through the Eastern Division, severely damaging the islands and diverse ecosystems of Northern Lau.
The objectives of this survey were to:
(a) collect data on the health, abundance and diversity of corals, reef fish and invertebrate species, in order to establish a baseline for long-term monitoring;
(b) document the damage to community fishing grounds caused by Cyclone Winston; and
(c) provide recommendations to communities on the management of their traditional fishing grounds to support food security and sustainable livelihoods.
A total of 33 sites of varying habitats were surveyed, including lagoon patch reefs, channels, and leeward and windward island fringing reefs. Profiles of each site were made to describe the reef type, current(s), exposure, reef structure and relief, habitat complexity and general observations.
The reefs showed results of the extreme isolation of these islands, pounded on windward sides by the large ocean swells of the Pacific with sheltered leeward sides.
A total of 47 coral genera were found across the sites, including massive and submassive Porites, Platygyra, Favites and Acanthastrea corals; and branching, plates, tabular and encrusting coral forms of Pocilliopora, Stylophora, Turbinaria, and Acropora.
The effect of Cyclone Winston was apparent on more than half the reefs sites surveyed. Hard coral was the dominant substrate with the highest cover recorded at Vatuvara Island (27.9%) and lowest at Adavaci Island (9.1%).
Reef systems in Northern Lau appeared to show a high degree of resilience to natural disturbances, likely a result of their exposure to extreme wave action and weather conditions.
A high number of fish species (293) was recorded during the survey. Overall, fish populations showed high diversity within the families Labridae, Pomacentridae,
Chaetodontidae, Acanthuridae and Scaridae. Mean fish biomass across all sites was remarkably high (1095.1 kg ha -1 ), with Vatuvara Island supporting the highest biomass (2180.3 kg ha -1 ).
Maintaining fish biomass above these reference levels promotes sustainable fish populations.
Populations of at least eight species listed on the 2017 IUCN Red List of threatened species were observed, including the globally endangered humphead wrasse (Cheilinus undulatus), four shark species and the endangered green turtle (Chelonia mydas) and hawksbill turtle (Eretmochelys imbricata).
Invertebrate populations were notably low, especially giant clams, sea cucumbers, crustaceans and urchins.
The biological data collected establishes a baseline understanding of the marine environment of the remote islands surveyed. The data will be used as reference for the long-term monitoring of these marine environments to detect potential changes.
The suite of early warning indicators of coral health and supporting water quality monitoring will help interpret changes to these critical marine habitats.
The findings from this study will be used to help revive and guide ocean conservation in Northern Lau through a network of community locally-managed marine areas, provide innovative solutions that promote environmental awareness and empower local communities to better manage their natural resources.
The study recommended:
- Actions should be taken to minimize human-stresses to coral reefs, especially areas that were impacted by Cyclone Winston;
- Protection of coral reefs that were undamaged, which may play a critical role in the recovery of adjacent impacted reefs;
- Recommendations to communities of key areas for conservation, including sites for inclusion in proposed networks of Locally-Marine Managed Areas (LMMAs) or Marine Protected Areas (MPAs) should be provided. Planning should be done in consultation with communities, respecting the traditional values, needs and aspirations of communities;
- Establish MPAs that are easily enforceable and targeting areas that are diverse, unique and provide refuge for threatened species;
- Livelihood programs for communities should be developed in order to relieve pressures from marine resources and support sustainable futures;
- A surveillance and enforcement strategy should be implemented to reduce threats to coral reefs; and
- A monitoring program to measure the recovery of coral reefs should be implemented over the next 2?5 years, and ensure it is linked to management
Download the complete report here: