Climate change is one of the greatest threats to the long-term maintenance of coral-dominated tropical ecosystems, and has received considerable attention over the past two decades. Coral bleaching and associated mortality events, which are predicted to become more frequent and intense, can alter the balance of different elements that are responsible for coral reef growth and maintenance. The geomorphic impacts of coral mass mortality have received relatively little attention, particularly questions concerning temporal recovery of reef carbonate production and the factors that promote resilience of reef growth potential. Here, we track the biological carbonate budgets of inner Seychelles reefs from 1994 to 2014, spanning the 1998 global bleaching event when these reefs lost more than 90% of coral cover. All 21 reefs had positive budgets in 1994, but in 2005 budgets were predominantly negative. By 2014, carbonate budgets on seven reefs were comparable with 1994, but on all reefs where an ecological regime shift to macroalgal dominance occurred, budgets remained negative through 2014. Reefs with higher massive coral cover, lower macroalgae cover and lower excavating parrotfish biomass in 1994 were more likely to have positive budgets post-bleaching. If mortality of corals from the 2016 bleaching event is as severe as that of 1998, our predictions based on past trends would suggest that six of eight reefs with positive budgets in 2014 would still have positive budgets by 2030. Our results highlight that reef accretion and framework maintenance cannot be assumed from the ecological state alone, and that managers should focus on conserving aspects of coral reefs that support resilient carbonate budgets.
New Publication: Kenyan and Mozambican coral reef ‘carbonate budgets’ contribute to international picture of corals under sea-level rise.
SPACES coral reef surveys have contributed to an international picture of how reefs might be able to grow to keep up with sea-level rise, recently published in Nature. The growth of coral reefs is strongly influenced by the amount and types of coral living on the reef surface, but across both regions this growth is […]
Artisanal fisheries in Cabo Delgado, Mozambique: rural vs urban fishing centers
This working paper investigates the relationship between gear, catch and income generated by the fishers in different seasons. SPACES researchers collected data using fish catch surveys at landing sites in Pemba town, Vamizi and Lalane. A standard questionnaire was used to collect the effort and location of the fishery. The fishery shows a wide range […]
Nereus Report: Predicting Future Oceans — Climate Change, Oceans & Fisheries
A report entitled “Predicting Future Oceans: Climate Change, Oceans & Fisheries” newly released by the Nereus program, an international interdisciplinary research program aimed at predicting future oceans, suggests that future seafood supply in the world will be substantially altered by climate change, overfishing and habitat destruction if we do not take actions.
Application of IPCC guidelines in monitoring, reporting and verification (MRV) of blue carbon in WIO countries – Lilian Mwihaki et al.(8.8 MB)
WIOMSA presentation on the concept on the evolution of climate change science and the limitations of the Intergovernmental Panel on Climate Change (IPCC). The Blue Carbon initiative created an internationally applicable standard for quantifying and measuring coastal carbon. The presentation finishes with recommendations for the way forward.
Changing dynamics of reef framework production in the Western Indian Ocean – Fraser Januchowski-Hartley et al.(1.2 MB)
Fraser Januchowski-Hartley’s presentation at the 2015 WIOMSA symposium on carbonate budget and current coral condition at SPACES sites, Mombasa, Shimoni, Vamizi, and Pemba.
Linking reef ecology to island building: Parrotfish identified as major producers of island-building sediment in the Maldives. Geology 2015
Reef islands are unique landforms composed entirely of sediment produced on the surrounding coral reefs. Despite the fundamental importance of these ecological-sedimentary links for island development and future maintenance, reef island sediment production regimes remain poorly quantified. Using census and sedimentary data from Vakkaru island (Maldives), a sand-dominated atoll interior island, we quantify the major […]
Remote coral reefs can sustain high growth potential and may match future sea-level trands. Nature Scientific Reports 2015
Climate-induced disturbances are contributing to rapid, global-scale changes in coral reef ecology. As a consequence, reef carbonate budgets are declining, threatening reef growth potential and thus capacity to track rising sea-levels. Whether disturbed reefs can recover their growth potential and how rapidly, are thus critical research questions. Here we address these questions by measuring the […]
Similar impacts of fishing and environmental stress on calcifying organisms in Indian Ocean coral reefs. Marine Ecology Press Series 2016
Calcification and reef growth processes dominated by corals and calcifying algae are threatened by climate and fishing disturbances. Twenty-seven environmental, habitat, and species interaction variables were tested for their influence on coral and calcifier cover in 201 western Indian Ocean coral reefs distributed across ~20° of latitude and longitude and up to 20 m deep. […]
Environmental variability indicates a climate-adaptive center under threat in northern Mozambique coral reefs. Ecosphere 2017
A priority for modern conservation is finding and managing regions with environmental and biodiversity portfolio characteristics that will promote adaptation and the persistence of species during times of rapid climate change. The latitudinal edges of high-diversity biomes are likely to provide a mixture of environmental gradients and biological diversity that meet the portfolio criteria needed […]
Ecological Underwater Surveys
All information including publications, conference presentations and news items related to underwater ecological surveys is tagged below.
New paper from SPACES team members shows the positive correlation between the orange-lined triggerfish and calcifier cover
SPACES Co-investigators, Tim McClanahan and Nyawira Muthiga, have recently published the paper, Similar impacts of fishing and environmental stress on calcifying organisms in Indian Ocean coral reefs (Open Access– free to read) in the Marine Ecology Progress Series. They investigated coral and calcifier cover in 201 western Indian Ocean reefs. McClanahan and Muthiga found that coral and calcifier cover […]
Aligning Global Indicators for Coral Reef Fisheries Monitoring in the Western Indian Ocean Workshop
Recently, a member of the SPACES team attended a regional workshop in Nosy Be, Madagascar from 27 to 28 April, 2015. The workshop was convened by the Wildlife Conservation Society (WCS) and Dr Emily Darling with the aim to bring together various researchers working on coral reef fisheries in the Western Indian Ocean (WIO). The workshop […]
How important are parrotfish for coral reef islands?
Parrotfishes are a beautiful, colourful and ubiquitous group of fishes that are present on coral reefs around the world. They’ve received a lot of attention due to their importance in both fisheries, and in how they can help to maintain coral reef health through preventing outbreaks of fleshy macroalgae, that can overgrow and out-compete corals. […]