Modelling Reef Fish Population Responses to Fisheries Restrictions in Marine Protected Areas in the Coral Triangle

Marine ecosystem models are used to investigate marine protected area (MPA) benefits for coral reef ecosystems located in Raja Ampat, in the heart of the Coral Triangle. Field data from an integrated and diverse research project is used to develop a spatial ecosystem model using Ecopath, Ecosim, and Ecospace modelling software. The ecological and fisheries responses of a reef ecosystem to different levels of fishing effort restrictions inside MPAs are explored. The trade-offs of allowing some fisheries to operate inside the MPAs versus designating the MPAs as no-take zones are highlighted. The results show that rapid rebuilding of reef fish populations, especially the large charismatic species, requires no-take areas. Distinct trade-offs in spillover benefits are observed between partially fished and no-take MPAs.

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Profil Terumbu Karang Pulau Kangean, Kabupaten Sumenep, Indonesia [Coral Reef Profile of Kangean Island, Sumenep District, Indonesia]

Jurnal Ilmiah Perikanan dan Kelautan ◽

10.20473/jipk.v10i2.10516 ◽

2018 ◽

Vol 10 (2) ◽

pp. 76

Author(s):

Apri Arisandi ◽

Badrud Tamam ◽

Achmad Fauzan

Keyword(s):

Coral Reef ◽

Reef Fish ◽

Coral Cover ◽

Marine Ecosystem ◽

Marine Biota ◽

Live Coral ◽

Visual Census ◽

Coral Reef Ecosystems ◽

Marine Ecotourism ◽

Line Intercept

Abstrak Ekosistem terumbu karang merupakan bagian dari ekosistem laut yang penting, karena menjadi sumber kehidupan bagi biota laut. Penelitian ini bertujuan untuk mengumpulkan data berupa persentase penutupan karang hidup, lifeform dan jumlah karang. Kelimpahan ikan karang dan kondisi perairan kepulauan yang terdapat ekosistem terumbu karang bisa menjadi dasar untuk mendukung kesesuaian suatu kawasan menjadi objek ekowisata bahari. Penelitian dilaksanakan pada bulan juli-Agustus dan dilakukan menggunakan metode Line Intercept Transect (LIT), sepanjang 50 meter sejajar garis pantai pada kedalaman 3 dan 10 meter. Persentase penutupan karang mengacu kepada lifeform dan data ikan karang diambil menggunakan metode pencacahan langsung (visual census). Hasil penelitian menunjukkan bahwa persentase tutupan karang berada pada kisaran 60-73% yang artinya kondisi ekosistem terumbu karang di Pulau Kangean adalah baik, dan merupakan habitat yang nyaman bagi ikan-ikan karang seperti spesies Apogon sp., Chelmon sp., Chaetodon sp., Lethrinus sp., dan Cheilodipterus sp. AbstractCoral reef ecosystems are part of an important marine ecosystem because they are a source of life for marine biota. This study was aimed to collect data in the form of a percentage of live coral cover, lifeform and number of corals. The abundance of reef fish and the condition of island waters that have coral reef ecosystems can be the basis for supporting the suitability of an area to become an object of marine ecotourism. The study was conducted in July-August and was carried out using the Line Intercept Transect (LIT) method, along 50 meters parallel to the coastline at depths of 3 and 10 meters. The percentage of coral cover refers to the lifeform and data on reef fish are taken using the visual census method. The results showed that the percentage of coral cover was in the range of 60-73%, which means that the condition of the coral reef ecosystem in Kangean Island is good, and is a comfortable habitat for reef fish such as the species Apogon sp., Chelmon sp., Chaetodon sp., Lethrinus sp., and Cheilodipterus sp.

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Adaptive time step algorithms for the simulation of marine ecosystem models using the transport matrix method implementation Metos3D (v0.5.0)

10.5194/gmd-2021-392 ◽

2022 ◽

Author(s):

Markus Pfeil ◽

Thomas Slawig

Keyword(s):

Marine Ecosystem ◽

Size Control ◽

Ecosystem Model ◽

Computational Effort ◽

Ecosystem Models ◽

Step Size ◽

Time Step ◽

Marine Ecosystem Model ◽

Marine Ecosystem Models ◽

Adaptive Step

Abstract. The reduction of the computational effort is desirable for the simulation of marine ecosystem models. Using a marine ecosystem model, the assessment and the validation of annual periodic solutions (i.e., steady annual cycles) against observational data are crucial to identify biogeochemical processes, which, for example, influence the global carbon cycle. For marine ecosystem models, the transport matrix method (TMM) already lowers the runtime of the simulation significantly and enables the application of larger time steps straightforwardly. However, the selection of an appropriate time step is a challenging compromise between accuracy and shortening the runtime. Using an automatic time step adjustment during the computation of a steady annual cycle with the TMM, we present in this paper different algorithms applying either an adaptive step size control or decreasing time steps in order to use the time step always as large as possible without any manual selection. For these methods and a variety of marine ecosystem models of different complexity, the accuracy of the computed steady annual cycle achieved the same accuracy as solutions obtained with a fixed time step. Depending on the complexity of the marine ecosystem model, the application of the methods shortened the runtime significantly. Due to the certain overhead of the adaptive method, the computational effort may be higher in special cases using the adaptive step size control. The presented methods represent computational efficient methods for the simulation of marine ecosystem models using the TMM but without any manual selection of the time step.

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An interactive atlas for marine biodiversity conservation in the Coral Triangle

Earth System Science Data ◽

10.5194/essd-11-163-2019 ◽

2019 ◽

Vol 11 (1) ◽

pp. 163-174 ◽

Cited By ~ 2

Author(s):

Irawan Asaad ◽

Carolyn J. Lundquist ◽

Mark V. Erdmann ◽

Mark J. Costello

Keyword(s):

Biodiversity Conservation ◽

Marine Protected Areas ◽

Spatial Information ◽

Marine Protected Area ◽

Marine Ecosystem ◽

Marine Biodiversity ◽

Coral Triangle ◽

Biodiversity Informatics ◽

Conservation Values ◽

Mpa Network

Abstract. An online atlas of the Coral Triangle region of the Indo-Pacific biogeographic realm was developed. This online atlas consists of the three interlinked parts: (1) Biodiversity Features; (2) Areas of Importance for Biodiversity Conservation; (3) recommended priorities for Marine Protected Area (MPA) Network Expansion (http://www.marine.auckland.ac.nz/CTMAPS). The first map, Biodiversity Features, provides comprehensive data on the region's marine protected areas and biodiversity features, threats, and environmental characteristics. The second provides spatial information on areas of high biodiversity conservation values, while the third map shows priority areas for expanding the current Coral Triangle MPA network. This atlas provides the most comprehensive biodiversity datasets that have been assembled for the region. The datasets were retrieved and generated systematically from various open-access sources. To engage a wider audience and to raise participation in biodiversity conservation, the maps were designed as an interactive and online atlas. This atlas presents representative information to promote a better understanding of the key marine and coastal biodiversity characteristics of the region and enables the application of marine biodiversity informatics to support marine ecosystem-based management in the Coral Triangle region.

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Supporting Ecosystem-based Fisheries Management in meeting multiple objectives for sustainable use of coral reef ecosystems

ICES Journal of Marine Science ◽

10.1093/icesjms/fsaa194 ◽

2020 ◽

Author(s):

Mariska Weijerman ◽

Zack S Oyafuso ◽

Kirsten M Leong ◽

Kirsten L L Oleson ◽

Morgan Winston

Keyword(s):

Coral Reef ◽

Fisheries Management ◽

Sustainable Use ◽

Ecosystem Model ◽

Ecological System ◽

Management Approach ◽

Social Ecological ◽

Trade Offs ◽

Coral Reef Ecosystems ◽

Ecosystem Based Fisheries Management

Abstract Ecosystem-based Fisheries Management is a holistic management approach that integrates the dynamics of an entire ecosystem, including societal dimensions. However, this approach seldom lives up to its promise because economic and social objectives are rarely specified. To fill this gap, we explored how an ecosystem model could better integrate economic and social objectives, using the coral reef ecosystem around Hawai`i as a case study. After meeting with stakeholders and conducting a literature review of policy/strategy documents, we identified societal and ecological objectives and associated performance indicators for which data existed. We developed a social–ecological system conceptual framework to illustrate the relationships between ecological and social state components. This framework was the foundation for the development of the final social–ecological system model which we simulated using an Ecopath with Ecosim model. We simulated four gear/species restrictions for the reef-based fishery, two fishing scenarios associated with the opening of hypothetical no-take Marine Protected Areas for the deepwater-based fishery, and a Constant Effort (No Action) scenario. Despite limitations in the model, our approach shows that when social and economic objectives and social–ecological relationships are defined, we can quantify the trade-offs among the identified societal objectives to support managers in choosing among alternative interventions.

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Impact of Ocean Acidification on Ecosystem Functioning and Services in Habitat-Forming Species and Marine Ecosystems

Ecosystems ◽

10.1007/s10021-021-00601-3 ◽

2021 ◽

Author(s):

Serena Zunino ◽

Simone Libralato ◽

Donata Melaku Canu ◽

Giulia Prato ◽

Cosimo Solidoro

Keyword(s):

Ecosystem Services ◽

Ocean Acidification ◽

Food Web ◽

Marine Protected Area ◽

Habitat Degradation ◽

Marine Ecosystem ◽

Ecosystem Model ◽

Posidonia Oceanica ◽

Ecosystem Development ◽

Cascading Effects

AbstractOcean acidification (OA) is expected to impact habitat-forming species (HFS), with cascading effects on the whole marine ecosystem and related services that are seldom quantified. Here, the changes in HFSs biomass due to OA are modeled using a food web ecosystem model, and the trophic and non-trophic cascading effects on the marine community are investigated. The food web model represents a well-studied coastal marine protected area in the NW Mediterranean Sea where coralligenous reefs and Posidonia oceanica meadows constitute important HFS. The model is used to implement 5 scenarios of habitat degradation, that is, reduction of HFS biomass, induced by increasing OA and to quantify the potential changes in ecosystem properties and indicators of ecosystem services over the next 100 years. The changes in ecosystem indicators highlight a decrease in the size of the system and a reorganization of energy flows suggesting a high degree of ecosystem development. All the proxies for ecosystem services show significant decreases in their values. Although representing only a portion of the possible impacts of OA, the findings are consistent with the idea that ecological systems can react to OA effects to maintain the level of ecosystem development, but the new organization might not be optimal from an anthropocentric viewpoint.

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Digital map of the Coral Triangle: An online atlas for marine biodiversity conservation

10.5194/essd-2018-80 ◽

2018 ◽

Author(s):

Irawan Asaad ◽

Carolyn J. Lundquist ◽

Mark V. Erdmann ◽

Mark J. Costello

Keyword(s):

Biodiversity Conservation ◽

Spatial Information ◽

Marine Protected Area ◽

Marine Ecosystem ◽

Marine Biodiversity ◽

Coral Triangle ◽

Digital Map ◽

Digital Maps ◽

Conservation Values ◽

Mpa Network

Abstract. An online atlas of the Coral Triangle region of the Indo Pacific biogeographic realm was developed. This online atlas consists of the three interlinked digital maps: (1) Biodiversity Features; (2) Areas of Importance for Biodiversity Conservation; (3) Recommended Priorities for Marine Protected Area (MPA) Network Expansion (www.marine.auckland.ac.nz/CTMAPS). The first map, Biodiversity Features, provides comprehensive data on the region's marine protected areas and biodiversity features, threats and environmental characteristics. The second provides spatial information on areas of high biodiversity conservation values, while the third map shows priority areas for expanding the current Coral Triangle MPA network. This digital map provides the most comprehensive biodiversity datasets yet assembled for the region. The datasets were retrieved and generated systematically from various open-access sources. To engage a wider audience and to raise participation in biodiversity conservation, the maps were designed as an interactive and online atlas. This digital map presents representative information to promote a better understanding of the key marine and coastal biodiversity characteristics of the region and enables the application of marine biodiversity informatics to support marine ecosystem-based management in the Coral Triangle region.

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