Papers by Sebastian Ferse
Fostering diversity, equity, and inclusion in interdisciplinary marine science
Authorea (Authorea), Mar 15, 2024
Anticipating and transforming futures: a literature review on transdisciplinary coastal research in the Global South
Ecosystems and people, Dec 16, 2023
Anticipation of futures using transdisciplinary approaches is critical to provide the basis for a... more Anticipation of futures using transdisciplinary approaches is critical to provide the basis for appropriate action to cope with current and future risks and to foster sustainability transformations. Coasts in the Global South in particular are subjected to severe environmental and societal challenges exacerbated by climate change. Yet, traditional research methods and epistemologies may not reflect the need for envisioning radically different sustainable futures. To gain an overview of and identify gaps in the current practices of transformational transdisciplinary research in coastal regions of the Global South, we conducted a systematic literature review of empirical English-language research articles (n?=?256). Our results showed that most of the articles reviewed focused on past and current state analysis. Those articles using anticipation methods rarely analysed or established a link between anticipation and sustainability transformation. Yet, transdisciplinary and anticipation research have synergistic effects to foster sustainability transformation. A combination of these approaches may integrate pluralistic voices and values of stakeholders and foster potential alternative visions to counter unsustainable narratives. Thereby, the visions for possible futures may become more inclusive and reflective of realities in the Global South. Anticipation of the future using transdisciplinary approaches can provide a basis for adaptive management of future environmental and societal challenges. It may provide the knowledge-base which can be used to identify, reduce or prevent governance actions that result in undesirable states of the future. The inclusion of anticipation and foresight in transdisciplinary research creates the potential for achieving or progressing towards innovative and sustainable visions of the future.
Cambridge Prisms: Coastal Futures
Post-industrial society is driving global environmental change, which is a challenge for all gene... more Post-industrial society is driving global environmental change, which is a challenge for all generations, current and future. The Anthropocene is the geological epoch in which humans dominate and it is rooted in the past, present, and future. Future sustainability is building on the momentum of the fundamental importance of studying human dynamics and governance of coupled social and ecological systems. In the Anthropocene, social innovation may play a critical role in achieving new pathways to sustainability. This conventional narrative review uses a qualitative analysis anchored in the Grounded Theory Method and a systematic collection and analysis of papers to identify broad types of social innovations. Scientific journal articles published since 2018 were prioritised for inclusion. The six types of social innovation proposed are (a) authentic engagement; (b) artful and engaging communication; (c) urging and compelling change; (d) governance for social-ecological systems; (e) ant...
Frontiers in Marine Science, Mar 30, 2022
Coral reefs host exceptionally diverse and abundant marine life. Connecting coasts and sheltered ... more Coral reefs host exceptionally diverse and abundant marine life. Connecting coasts and sheltered lagoons to the open ocean, reef passages are important yet poorly studied components of these ecosystems. Abiotic and biotic elements 'pass' through these reef passages, supporting critical ecological processes (e.g. fish spawning). Reef passages provide multiple social and ecological benefits for islands and their peoples, but are so far neither characterized nor recognized for their multifaceted significance. This study investigated 113 reef passages across nine Pacific islands (Fiji, New Caledonia, Vanuatu). GIS-based visual interpretations of satellite imagery were used to develop criteria to define three distinct types, mainly based on distance to coastline and presence/ absence of an enclosed water body. The discussion identifies ways to refine and augment this preliminary typology as part of a research agenda for reef passages. With these next steps, this typology will be extendable to other regions to better document reef passages and their various roles, supporting biodiversity conservation and sustainable fisheries management.
Journal of Sustainability Science and Management, 2024
Corals have many growth forms, creating many nooks and crannies which
provide specialised places ... more Corals have many growth forms, creating many nooks and crannies which
provide specialised places for marine organisms to shelter, live and breed. Reef rugosity is a simple surface roughness measurement; a high rugosity value will support fish communities. This research measured the differences in reef rugosities in four islands in Spermonde Archipelago, Indonesia, based on their distance from the mainland and the reef depth. Observation sites were Lae–Lae (LL; inshore zone), Samalona and Barrang Lompo (SA and BL; inner mid-shelf zone), and Kapoposang (KP; outer zone). At each station, rugosity was measured on the reef slope in two depth zones 3-5 m shallow and 6-10 m deep using chains. The rugosity index at shallow reefs was increasing towards outer zones (Lae Lae: 0.143 ± 0.015; Kapoposang 0.655 ± 0.133), which means shallow reefs further from the Sulawesi mainland have more complex structures. There are differences between sites (P-value: 0.0000641) namely LL-BL sites (0.0001675), SA-BL (0.0001873),
LL-KP (0.0016070), and SA-KP (0.0018514). At deeper depths, the rugosity was varied with Kapoposang having a higher value (0.451 ± 0.207). The inshore-offshore rugosity patterns in the four sampled islands are likely linked to anthropogenic pressures from the mainland of Sulawesi.
The main effects of El Niño and La Niña on fish are increases in mortality rates, abundance and r... more The main effects of El Niño and La Niña on fish are increases in mortality rates, abundance and recruitment variation, and expansion/restriction in the range of distribution and spawning areas. Potentially, the interactions with seasonal effects can further exacerbate or dampen fluctuations in these parameters. The objective of this work, therefore, was to characterize the possible differences in the reef fish community structure in two seasons of the year (warm/cold) and between years (2010/2012) following El Niño-La Niña events. There were no significant differences in mean species richness between years. Furthermore, although more than twice the number of individuals was observed in the year after La Niña (2012) compared to the year following El Niño (2010), there were no significant differences with respect to mean abundance per transect. The total number of species recorded was slightly higher in the cold season, with 68 species across both years. In contrast, the total abundance was higher in the warm season. However, differences between seasons were neither significant for mean species richness nor for mean abundance. Neither season nor year exhibited a significant effect on community composition. The cold season in the Gulf of California is characterized by intense winds which generate a greater mixed layer; this, in turn, increases productivity, with cascading effects on higher trophic levels. In contrast, the presence of nitrogen-fixing picocyanobacteria which increase the levels of primary production may be a factor leading to maintaining a similar fish abundance in the warm season. Fluctuations between seasons and years of study were observed for some individual species, which may be related to oceanic productivity and reproductive periods. The results obtained in this work indicate that seasonality and climatic phenomena such El Niño and La Niña do not have a marked effect on community attributes of rocky reef fish in the southern Gulf of California, which apparently form a seasonally stable community, despite some fluctuations in individual species.
Marine Pollution Bulletin, 2016
Jakarta Bay, next to the Jakarta Metropolitan Area with around 30 million inhabitants, is facing ... more Jakarta Bay, next to the Jakarta Metropolitan Area with around 30 million inhabitants, is facing extreme pollution. Although local coral reefs are degraded and marine resources heavily exploited, they provide livelihoods for millions of people. This study investigates anthropogenic pressures on local fisheries resources and associated livelihoods. Questionnaire surveys were conducted in 15 coastal communities (10 coastal neighborhoods in Jakarta Bay on the mainland and 5 of the offshore Thousand Islands). The most economically valuable species were Caesio cuning (Redbelly yellowtail fusilier) on the islands and Rastrelliger kanagurta (Indian mackerel) on the mainland. Over 80% of all interviewed fishermen regarded the current state of marine resources as declining, mainly due to pollution and overexploitation. While perceptions of declining resources were equally high on the islands and the mainland, pollution was listed as the principal cause of degradation significantly more on the mainland. Findings are discussed in the context of coastal livelihood vulnerability.
Coastal Futures, 2023
Post-industrial society is driving global environmental change, which is a challenge for all gene... more Post-industrial society is driving global environmental change, which is a challenge for all generations, current and future. The Anthropocene is the geological epoch in which humans dominate and it is rooted in the past, present, and future. Future sustainability is building on the momentum of the fundamental importance of studying human dynamics and governance of coupled social and ecological systems. In the Anthropocene, social innovation may play a critical role in achieving new pathways to sustainability. This conventional narrative review uses a qualitative analysis anchored in the Grounded Theory Method and a systematic collection and analysis of papers to identify broad types of social innovations. Scientific journal articles published since 2018 were prioritised for inclusion. The six types of social innovation proposed are (a) authentic engagement; (b) artful and engaging communication; (c) urging and compelling change; (d) governance for social-ecological systems; (e) anticipation in governance; and (f) lived experiences and values. The six innovations proposed in this paper can be embedded within, and form part of, social action using a science-society compact for the sustainable development of coasts in the Anthropocene. Impact statement This paper reflects on the need for sustainability of the coasts in the Anthropocene. It considers the increasing need for science to engage with society to achieve sustainable coastal futures. In the human-dominated system of the future, fact, or scientific evidence alone is not sufficient for society to adapt and transform towards higher degrees of sustainability. We propose that there are interventions and actions at the science-society interface that are needed to enable such higher degrees of sustainability. The paper identifies six social innovations knowable through the scientific literature that have the potential to substantially increase the ability of society to transform to coastal sustainability. These six social innovations are also critical for enabling the achievement of the UN Sustainable Development Goals. The six innovations proposed in this paper can be bound together with social action and interest in a new science-society compact for sustainable coasts in the Anthropocene. Recent scientific literature reflects on the meaning and relevance of the future (of humanity) for virtually all aspects of human existence as part of social-ecological systems (also known as coupled human-natural systems and complex adaptive systems) (Hulme, 2020; Wyborn et al.,
Reviews in Fish Biology and Fisheries, 2023
Fisher-trader relations are influential in many small-scale fisheries worldwide. The ability to i... more Fisher-trader relations are influential in many small-scale fisheries worldwide. The ability to influence emergent fishing practices has shifted traders into focus of fisheries policy-making. Formal policies could be more effective if they were complementary to and build on an understanding of the role of traders, their interaction with fishers, and how these contribute to the emergence of compliant or noncompliant fishing practices. Here, we first compared fishing practices with policies to assess the latter's effectiveness in Indonesia, Spermonde. Second, we identified the roles and interactions of fisher-trader relations in shaping emergent fishing practices using the social-ecological action situation framework. We found that 6 out of 7 fishing practices were at least partially non-compliant with formal policies. Second, fisher-trader relations mediated by social norms enabled more fishing practices to emerge than those focused solely on selling and buying fish. Third, traders' interactions with other fishery actors enabled non-compliant fishing practices. These findings comprehensively characterize fishers' and traders' roles and interactions in the emergence of fishing practices. Policy effectiveness could be enhanced by engaging in traders' interactions with other fishery actors.
Frontiers in Ocean Sustainability, Sep 26, 2023
) Grand challenges in marine governance for ocean sustainability in the twenty-first century.
Frontiers in Marine Science, Sep 24, 2023
Introduction: Coral bleaching immediately impacts the reef benthos, but effects on fish communiti... more Introduction: Coral bleaching immediately impacts the reef benthos, but effects on fish communities are less well understood because they are often delayed and confounded by anthropogenic interactions. Methods: We assessed changes in fish abundance, biomass and community composition before and after the 2015/16 coral bleaching event at Aldabra Atoll, Seychelles, where local human impacts are minimal, but reefs suffered 50% bleaching-induced coral mortality. We monitored 12 shallow (2-5 m water depth) and nine deep (15 m water depth) permanent survey sites using two survey methods: indicator surveys recording 84 taxa over six years (pre-: 2014; post-bleaching: 2016-2019, 2021), sizing fish based on six size-class categories, and extended fish surveys recording 198 taxa over two years (pre-: 2015; postbleaching: 2020) with size estimates to the nearest cm (excluding fish < 8 cm). Results: During indicator surveys, mean fish abundance did not change on deep reefs. However, abundance increased by 77% on shallow reefs between 2014 and 2016, which was mainly driven by increases in herbivores and omnivores, likely as a response to elevated turf algae cover following coral mortality. Overall (and functional group-specific) indicator fish biomass did not differ between 2014 and 2016 and remained at or above pre-bleaching levels throughout 2016-2021. In contrast, extended fish surveys in 2015 and 2020 showed a 55-60% reduction in overall abundance on shallow and deep reefs, and a 69% reduction in biomass on Frontiers in Marine Science frontiersin.org 01
Sustainably managing fisheries requires regular and reliable evaluation of stock status. However,... more Sustainably managing fisheries requires regular and reliable evaluation of stock status. However, most multispecies reef fisheries around the globe tend to be data-poor and lack research and monitoring capacity (e.g., long-term fishery data), preventing the estimation of sustainable reference points against which stocks can be assessed. Here, combining fish biomass data for more than 2000 coral reefs with catch estimates from 99 jurisdictions, we estimate site-specific sustainable reference points for coral reef fisheries and use these to assess the status of coral reef fish stocks. We reveal that more than half of jurisdictions with available information have stocks of conservation concern, having failed at least one fisheries sustainability benchmark. We quantify the trade-offs between biodiversity, mean fish length, and ecosystem functions relative to key benchmarks and highlight the ecological benefits of increasing sustainability. Our approach yields multispecies sustainable re...
Frontiers in Marine Science, 2023
Coral bleaching immediately impacts the reef benthos, but effects on fish communities are less we... more Coral bleaching immediately impacts the reef benthos, but effects on fish communities are less well understood because they are often delayed and confounded by anthropogenic interactions.
Methods: We assessed changes in fish abundance, biomass and community composition before and after the 2015/16 coral bleaching event at Aldabra Atoll, Seychelles, where local human impacts are minimal, but reefs suffered 50% bleaching-induced coral mortality. We monitored 12 shallow (2–5 m water depth) and nine deep (15 m water depth) permanent survey sites using two survey methods: indicator surveys recording 84 taxa over six years (pre-: 2014; post-bleaching: 2016–2019, 2021), sizing fish based on six size-class categories, and extended fish surveys recording 198 taxa over two years (pre-: 2015; post-bleaching: 2020) with size estimates to the nearest cm (excluding fish < 8 cm).
Results: During indicator surveys, mean fish abundance did not change on deep reefs. However, abundance increased by 77% on shallow reefs between 2014 and 2016, which was mainly driven by increases in herbivores and omnivores, likely as a response to elevated turf algae cover following coral mortality. Overall (and functional group-specific) indicator fish biomass did not differ between 2014 and 2016 and remained at or above pre-bleaching levels throughout 2016–2021. In contrast, extended fish surveys in 2015 and 2020 showed a 55–60% reduction in overall abundance on shallow and deep reefs, and a 69% reduction in biomass on shallow reefs, with decreases in biomass occurring in all functional groups. Biomass on deep reefs did not differ between 2015 and 2020. Multivariate analysis of both data sets revealed immediate and long-lasting differences between pre- and post-bleaching fish community compositions, driven largely by herbivorous, omnivorous and piscivorous taxa.
Discussion: Results from the indicator surveys suggest that the bleaching event had limited impact on fish abundance and biomass, while the extended surveys recorded changes in abundance and biomass which would otherwise have gone undetected. Our findings improve understanding of the shift a broad community of fish undergoes following a mass coral bleaching event and highlights the value of survey methods that include the full suite of species to detect ecological responses to environmental drivers.
Frontiers in Ocean Sustainability, 2023
The twenty-first century is seeing multiple and accelerating anthropogenic threats to the Ocean w... more The twenty-first century is seeing multiple and accelerating anthropogenic threats to the Ocean which jeopardize the planetary system and human well-being. Given the urgency of this planetary emergency, ensuring Ocean sustainability and an equitable and just future for humanity and the planet requires unprecedented acceleration and innovation in the theory and practice of marine governance. This Perspective provides an overview of recent trends and emerging issues facing the Ocean. It outlines a number of Grand Challenges, or important areas to advance for scholars and practitioners of marine governance, namely the bridging of sectors and scales, connecting people and the seas, consideration of inclusivity, equity and justice, and innovating knowledge generation and the interface of science, society and policy. This will allow to address questions of how to achieve just, equitable and sustainable use of and interaction with the Ocean in the twenty-first century.
Ecosystems and People, 2023
Anticipation of futures using transdisciplinary approaches is critical to provide the basis for a... more Anticipation of futures using transdisciplinary approaches is critical to provide the basis for appropriate action to cope with current and future risks and to foster sustainability transformations. Coasts in the Global South in particular are subjected to severe environmental and societal challenges exacerbated by climate change. Yet, traditional research methods and epistemologies may not reflect the need for envisioning radically different sustainable futures. To gain an overview of and identify gaps in the current practices of transformational transdisciplinary research in coastal regions of the Global South, we conducted a systematic literature review of empirical English-language research articles (n?=?256). Our results showed that most of the articles reviewed focused on past and current state analysis. Those articles using anticipation methods rarely analysed or established a link between anticipation and sustainability transformation. Yet, transdisciplinary and anticipation research have synergistic effects to foster sustainability transformation. A combination of these approaches may integrate pluralistic voices and values of stakeholders and foster potential alternative visions to counter unsustainable narratives. Thereby, the visions for possible futures may become more inclusive and reflective of realities in the Global South. Anticipation of the future using transdisciplinary approaches can provide a basis for adaptive management of future environmental and societal challenges. It may provide the knowledge-base which can be used to identify, reduce or prevent governance actions that result in undesirable states of the future. The inclusion of anticipation and foresight in transdisciplinary research creates the potential for achieving or progressing towards innovative and sustainable visions of the future.
Scientific Reports, 2024
Mangrove trees occur in a variety of geomorphic and sedimentary settings. Yet, studies investigat... more Mangrove trees occur in a variety of geomorphic and sedimentary settings. Yet, studies investigating their role as habitat providers often focus on the most common biophysical types, such as deltaic, estuarine, open coast or lagoonal mangroves on soft sediments, disregarding less typical environments. Here, we investigated the influence of individual mangrove trees growing on a consolidated backreef system (Laucala Bay, Fiji) on habitat use by reef fishes. Combining field surveys and an experiment, we quantified the extent to which reef mangrove trees serve as habitat for solitary or shoaling reef fishes. Using mangrove tree mimics, we disentangled effects attributable to the physical structure of trees from those related to their biochemical properties. We found that fish numbers were 3.7 times higher within close proximity to the mangrove trees than at control sites and correlated significantly with root system perimeter. The roots of larger trees sheltered aggregations of juveniles and adults at incoming and high tides. Mangrove trees and mimics attracted fishes alike. We show that mangrove trees on backreefs provide habitat for shoaling and adult reef fishes in addition to serving as nursery areas, an ecosystem service otherwise lacking on backreef areas with low structural complexity.
Frontiers in Ocean Sustainability, 2024
Effective ocean governance plays a critical role in managing and coordinating human activities, p... more Effective ocean governance plays a critical role in managing and coordinating human activities, policies, and institutions to ensure the sustainable use and conservation of marine resources. Recognizing the importance of effective ocean governance, there is a growing awareness that new research approaches are needed to bring together actors from academia and non-academic sectors. Together they need to develop transformative science solutions for a more inclusive and equitable ocean governance system. Despite widespread interest in this collaborative endeavor, limited resources are available to provide structured support and training. This creates a pressing need to develop capacity and promote a shared understanding of collaborative research methodologies, such as co-design. In response to the need for capacity development in such methodologies, the “Co-design for the Ocean Decade” online training course was launched in collaboration with IOC-UNESCO in 2022, starting with a first pilot course in the African region. This first co-design training course under the Ocean Decade framework serves as a practical and research-backed model for future co-design training programs in other regions. The evaluation results of the course reveal its effectiveness in enhancing participants' knowledge and skills in key co-design areas, particularly in communication with stakeholders. The evaluation also highlights areas for improvement, such as the need for (i) monitoring and evaluation, and (ii) follow-up opportunities for practice and funding support. Based on the evaluation, for future research and training programs, we recommend: (1) to incorporate local and regional context into the training, (2) to integrate co-design training into ocean science education, and (3) to embed co-design of research and training into the capacity development program of the Ocean Decade.
Marine Environmental Research, 2024
Trace metals are one of the most serious pollutants in tropical seagrass meadows given their pers... more Trace metals are one of the most serious pollutants in tropical seagrass meadows given their persistence and toxicity. Whereas quantity is frequently measured, there is no information on the spatial extent of metal pollution in these systems. Here, we use an island in Indonesia (Barang Lompo) as a model system to study the impact radius of two major and eight trace metals in sediment and seagrass leaves. We provide evidence for exponential decay in both the metal pollution index and concentrations of most metals with increasing distance from the island (k = − 0.01 to − 0.08 m-1). Consequently, there is an impact radius of approximately 100 m around the island. The comparative analysis of both seagrass species further revealed interspecific differences in metal loads. This study highlights the importance of assessing the spatial extent of metal pollution in addition to its quantity.
Ecosystems and People, 2023
Anticipation of futures using transdisciplinary approaches is critical to provide the basis for a... more Anticipation of futures using transdisciplinary approaches is critical to provide the basis for appropriate action to cope with current and future risks and to foster sustainability transformations. Coasts in the Global South in particular are subjected to severe environmental and societal challenges exacerbated by climate change. Yet, traditional research methods and epistemologies may not reflect the need for envisioning radically different sustainable futures. To gain an overview of and identify gaps in the current practices of transformational transdisciplinary research in coastal regions of the Global South, we conducted a systematic literature review of empirical English-language research articles (n?=?256). Our results showed that most of the articles reviewed focused on past and current state analysis. Those articles using anticipation methods rarely analysed or established a link between anticipation and sustainability transformation. Yet, transdisciplinary and anticipation research have synergistic effects to foster sustainability transformation. A combination of these approaches may integrate pluralistic voices and values of stakeholders and foster potential alternative visions to counter unsustainable narratives. Thereby, the visions for possible futures may become more inclusive and reflective of realities in the Global South. Anticipation of the future using transdisciplinary approaches can provide a basis for adaptive management of future environmental and societal challenges. It may provide the knowledge-base which can be used to identify, reduce or prevent governance actions that result in undesirable states of the future. The inclusion of anticipation and foresight in transdisciplinary research creates the potential for achieving or progressing towards innovative and sustainable visions of the future.
Nature Communications
Anthropogenic pressures are restructuring coral reefs globally. Sound predictions of the expected... more Anthropogenic pressures are restructuring coral reefs globally. Sound predictions of the expected changes in key reef functions require adequate knowledge of their drivers. Here we investigate the determinants of a poorly-studied yet relevant biogeochemical function sustained by marine bony fishes: the excretion of intestinal carbonates. Compiling carbonate excretion rates and mineralogical composition from 382 individual coral reef fishes (85 species and 35 families), we identify the environmental factors and fish traits that predict them. We find that body mass and relative intestinal length (RIL) are the strongest predictors of carbonate excretion. Larger fishes and those with longer intestines excrete disproportionately less carbonate per unit mass than smaller fishes and those with shorter intestines. The mineralogical composition of excreted carbonates is highly conserved within families, but also controlled by RIL and temperature. These results fundamentally advance our under...
Uploads
Papers by Sebastian Ferse
provide specialised places for marine organisms to shelter, live and breed. Reef rugosity is a simple surface roughness measurement; a high rugosity value will support fish communities. This research measured the differences in reef rugosities in four islands in Spermonde Archipelago, Indonesia, based on their distance from the mainland and the reef depth. Observation sites were Lae–Lae (LL; inshore zone), Samalona and Barrang Lompo (SA and BL; inner mid-shelf zone), and Kapoposang (KP; outer zone). At each station, rugosity was measured on the reef slope in two depth zones 3-5 m shallow and 6-10 m deep using chains. The rugosity index at shallow reefs was increasing towards outer zones (Lae Lae: 0.143 ± 0.015; Kapoposang 0.655 ± 0.133), which means shallow reefs further from the Sulawesi mainland have more complex structures. There are differences between sites (P-value: 0.0000641) namely LL-BL sites (0.0001675), SA-BL (0.0001873),
LL-KP (0.0016070), and SA-KP (0.0018514). At deeper depths, the rugosity was varied with Kapoposang having a higher value (0.451 ± 0.207). The inshore-offshore rugosity patterns in the four sampled islands are likely linked to anthropogenic pressures from the mainland of Sulawesi.
Methods: We assessed changes in fish abundance, biomass and community composition before and after the 2015/16 coral bleaching event at Aldabra Atoll, Seychelles, where local human impacts are minimal, but reefs suffered 50% bleaching-induced coral mortality. We monitored 12 shallow (2–5 m water depth) and nine deep (15 m water depth) permanent survey sites using two survey methods: indicator surveys recording 84 taxa over six years (pre-: 2014; post-bleaching: 2016–2019, 2021), sizing fish based on six size-class categories, and extended fish surveys recording 198 taxa over two years (pre-: 2015; post-bleaching: 2020) with size estimates to the nearest cm (excluding fish < 8 cm).
Results: During indicator surveys, mean fish abundance did not change on deep reefs. However, abundance increased by 77% on shallow reefs between 2014 and 2016, which was mainly driven by increases in herbivores and omnivores, likely as a response to elevated turf algae cover following coral mortality. Overall (and functional group-specific) indicator fish biomass did not differ between 2014 and 2016 and remained at or above pre-bleaching levels throughout 2016–2021. In contrast, extended fish surveys in 2015 and 2020 showed a 55–60% reduction in overall abundance on shallow and deep reefs, and a 69% reduction in biomass on shallow reefs, with decreases in biomass occurring in all functional groups. Biomass on deep reefs did not differ between 2015 and 2020. Multivariate analysis of both data sets revealed immediate and long-lasting differences between pre- and post-bleaching fish community compositions, driven largely by herbivorous, omnivorous and piscivorous taxa.
Discussion: Results from the indicator surveys suggest that the bleaching event had limited impact on fish abundance and biomass, while the extended surveys recorded changes in abundance and biomass which would otherwise have gone undetected. Our findings improve understanding of the shift a broad community of fish undergoes following a mass coral bleaching event and highlights the value of survey methods that include the full suite of species to detect ecological responses to environmental drivers.