Search

Your search keyword '"Ronald Mambrasar"' showing total 6 results
Start Over Author "Ronald Mambrasar" Database OpenAIRE
6 results on '"Ronald Mambrasar"'

1. Population estimates of photo-identified individuals using a modified POPAN model reveal that Raja Ampat’s reef manta rays are thriving

Author

Edy Setyawan, Ben C. Stevenson, Mark V. Erdmann, Abdi W. Hasan, Abraham B. Sianipar, Imanuel Mofu, Mochamad I. H. Putra, Muhamad Izuan, Orgenes Ambafen, Rachel M. Fewster, Robin Aldridge-Sutton, Ronald Mambrasar, and Rochelle Constantine

Subjects
Global and Planetary Change, Ocean Engineering, Aquatic Science, Oceanography, Water Science and Technology
Abstract

The 6.7-million-hectare Raja Ampat archipelago is home to Indonesia’s largest reef manta ray (Mobula alfredi) population and a representative network of nine marine protected areas (MPAs). However, the population dynamics of M. alfredi in the region are still largely unknown. Using our photo-identification database, we fitted modified POPAN mark-recapture models with transience and per capita recruitment parameters to estimate key demographic characteristics of M. alfredi from two of Raja Ampat’s largest MPAs: Dampier Strait and South East (SE) Misool. A total of 1,041 unique individuals were photo-identified over an 11-year period (2009–2019) from Dampier Strait (n = 515) and SE Misool (n = 536). In our models, apparent survival probabilities and per capita recruitment rates were strongly linked with El Niño–Southern Oscillation (ENSO) events. Our models also estimated high apparent survival probabilities and significant increases in (sub)population sizes in both MPAs over a decade. In Dampier Strait, the estimated population size increased significantly (p = 0.018) from 226 (95% CI: 161, 283) to 317 (280, 355) individuals. Likewise, the estimated population size in SE Misool increased significantly (p = 0.008) from 210 (137, 308) to 511 (393, 618) individuals. Regardless of variation in the percentage change in population size between years throughout the study, the estimated overall population change shows a compound growth of 3.9% (0.7, 8.6) per annum in Dampier Strait and 10.7% (4.3, 16.1) per annum in SE Misool. Despite the global decline in oceanic sharks and rays due to fishing pressure in the last five decades, our study demonstrates the positive impact of a suite of long-term conservation efforts, coupled with the influence of ENSO events, on increasing M. alfredi abundance in Raja Ampat MPAs. Our study also underscores the importance of long-term monitoring to evaluate the effectiveness of conservation management measures on manta ray populations. Our modification of the standard POPAN model by incorporating per capita recruitment and transience parameters represents an important advance in mark-recapture modelling that should prove useful when examining other manta ray populations and other highly migratory species that are likely to have a substantial percentage of transient individuals.

Published
2022
Full Text
View/download PDF

2. Diving into the vertical dimension of elasmobranch movement ecology

Author

Samantha Andrzejaczek, Tim C.D. Lucas, Maurice C. Goodman, Nigel E. Hussey, Amelia J. Armstrong, Aaron Carlisle, Daniel M. Coffey, Adrian C. Gleiss, Charlie Huveneers, David M. P. Jacoby, Mark G. Meekan, Johann Mourier, Lauren R. Peel, Kátya Abrantes, André S. Afonso, Matthew J. Ajemian, Brooke N. Anderson, Scot D. Anderson, Gonzalo Araujo, Asia O. Armstrong, Pascal Bach, Adam Barnett, Mike B. Bennett, Natalia A. Bezerra, Ramon Bonfil, Andre M. Boustany, Heather D. Bowlby, Ilka Branco, Camrin D. Braun, Edward J. Brooks, Judith Brown, Patrick J. Burke, Paul Butcher, Michael Castleton, Taylor K. Chapple, Olivier Chateau, Maurice Clarke, Rui Coelho, Enric Cortes, Lydie I. E. Couturier, Paul D. Cowley, Donald A. Croll, Juan M. Cuevas, Tobey H. Curtis, Laurent Dagorn, Jonathan J. Dale, Ryan Daly, Heidi Dewar, Philip D. Doherty, Andrés Domingo, Alistair D. M. Dove, Michael Drew, Christine L. Dudgeon, Clinton A. J. Duffy, Riley G. Elliott, Jim R. Ellis, Mark V. Erdmann, Thomas J. Farrugia, Luciana C. Ferreira, Francesco Ferretti, John D. Filmalter, Brittany Finucci, Chris Fischer, Richard Fitzpatrick, Fabien Forget, Kerstin Forsberg, Malcolm P. Francis, Bryan R. Franks, Austin J. Gallagher, Felipe Galvan-Magana, Mirta L. García, Troy F. Gaston, Bronwyn M. Gillanders, Matthew J. Gollock, Jonathan R. Green, Sofia Green, Christopher A. Griffiths, Neil Hammerschlag, Abdi Hasan, Lucy A. Hawkes, Fabio Hazin, Matthew Heard, Alex Hearn, Kevin J. Hedges, Suzanne M. Henderson, John Holdsworth, Kim N. Holland, Lucy A. Howey, Robert E. Hueter, Nicholas E. Humphries, Melanie Hutchinson, Fabrice R. A. Jaine, Salvador J. Jorgensen, Paul E. Kanive, Jessica Labaja, Fernanda O. Lana, Hugo Lassauce, Rebecca S. Lipscombe, Fiona Llewellyn, Bruno C. L. Macena, Ronald Mambrasar, Jaime D. McAllister, Sophy R. McCully Phillips, Frazer McGregor, Matthew N. McMillan, Lianne M. McNaughton, Sibele A. Mendonça, Carl G. Meyer, Megan Meyers, John A. Mohan, John C. Montgomery, Gonzalo Mucientes, Michael K. Musyl, Nicole Nasby-Lucas, Lisa J. Natanson, John B. O’Sullivan, Paulo Oliveira, Yannis P. Papastamtiou, Toby A. Patterson, Simon J. Pierce, Nuno Queiroz, Craig A. Radford, Andy J. Richardson, Anthony J. Richardson, David Righton, Christoph A. Rohner, Mark A. Royer, Ryan A. Saunders, Matthias Schaber, Robert J. Schallert, Michael C. Scholl, Andrew C. Seitz, Jayson M. Semmens, Edy Setyawan, Brendan D. Shea, Rafid A. Shidqi, George L. Shillinger, Oliver N. Shipley, Mahmood S. Shivji, Abraham B. Sianipar, Joana F. Silva, David W. Sims, Gregory B. Skomal, Lara L. Sousa, Emily J. Southall, Julia L. Y. Spaet, Kilian M. Stehfest, Guy Stevens, Joshua D. Stewart, James A. Sulikowski, Ismail Syakurachman, Simon R. Thorrold, Michele Thums, David Tickler, Mariana T. Tolloti, Kathy A. Townsend, Paulo Travassos, John P. Tyminski, Jeremy J. Vaudo, Drausio Veras, Laurent Wantiez, Sam B. Weber, R.J. David Wells, Kevin C. Weng, Bradley M. Wetherbee, Jane E. Williamson, Matthew J. Witt, Serena Wright, Kelly Zilliacus, Barbara A. Block, David J. Curnick, Andrzejaczek, Samantha [0000-0002-9929-7312], Lucas, Tim CD [0000-0003-4694-8107], Goodman, Maurice C [0000-0002-6874-2313], Hussey, Nigel E [0000-0002-9050-6077], Armstrong, Amelia J [0000-0001-8103-4314], Carlisle, Aaron [0000-0003-0796-6564], Coffey, Daniel M [0000-0001-5983-0146], Huveneers, Charlie [0000-0001-8937-1358], Jacoby, David MP [0000-0003-2729-3811], Meekan, Mark G [0000-0002-3067-9427], Mourier, Johann [0000-0001-9019-1717], Peel, Lauren R [0000-0001-6960-5663], Abrantes, Kátya [0000-0001-7430-8428], Afonso, André S [0000-0001-9129-278X], Ajemian, Matthew J [0000-0002-2725-4030], Anderson, Brooke N [0000-0003-4299-3496], Araujo, Gonzalo [0000-0002-4708-3638], Armstrong, Asia O [0000-0002-9307-0598], Barnett, Adam [0000-0001-7430-8428], Bennett, Mike B [0000-0001-8051-0040], Bezerra, Natalia A [0000-0002-4203-8408], Bonfil, Ramon [0000-0002-5753-464X], Boustany, Andre M [0000-0001-5501-7190], Bowlby, Heather D [0000-0002-2532-3725], Branco, Ilka [0000-0001-8136-2596], Braun, Camrin D [0000-0002-9317-9489], Brooks, Edward J [0000-0001-5206-7133], Burke, Patrick J [0000-0002-7217-0215], Butcher, Paul [0000-0001-7338-6037], Castleton, Michael [0000-0001-9639-6967], Chapple, Taylor K [0000-0002-0357-0223], Chateau, Olivier [0000-0003-1153-6284], Coelho, Rui [0000-0003-3813-5157], Cortes, Enric [0000-0001-6001-2482], Couturier, Lydie IE [0000-0002-3885-3397], Cuevas, Juan M [0000-0003-0086-5963], Curtis, Tobey H [0000-0003-0164-7335], Dale, Jonathan J [0000-0001-8565-3841], Daly, Ryan [0000-0002-4409-6951], Dewar, Heidi [0000-0002-8202-1387], Doherty, Philip D [0000-0001-7561-3731], Domingo, Andrés [0000-0002-1793-7663], Dove, Alistair DM [0000-0003-3239-4772], Drew, Michael [0000-0002-5109-7792], Dudgeon, Christine L [0000-0001-5059-7886], Duffy, Clinton AJ [0000-0002-3352-1609], Elliott, Riley G [0000-0003-0234-5953], Erdmann, Mark V [0000-0002-3644-8347], Farrugia, Thomas J [0000-0001-9052-8826], Ferreira, Luciana C [0000-0001-6755-2799], Ferretti, Francesco [0000-0001-9510-3552], Finucci, Brittany [0000-0003-1315-2946], Forget, Fabien [0000-0002-4845-4277], Forsberg, Kerstin [0000-0002-1233-9381], Franks, Bryan R [0000-0003-4016-9225], Gallagher, Austin J [0000-0003-1515-3440], García, Mirta L [0000-0003-0143-7397], Gaston, Troy F [0000-0003-0049-0831], Gillanders, Bronwyn M [0000-0002-7680-2240], Green, Jonathan R [0000-0001-7671-6716], Green, Sofia [0000-0002-2878-5984], Griffiths, Christopher A [0000-0001-7203-0426], Hammerschlag, Neil [0000-0001-9002-9082], Hawkes, Lucy A [0000-0002-6696-1862], Hearn, Alex [0000-0002-4986-098X], Hedges, Kevin J [0000-0002-2219-2360], Holland, Kim N [0000-0003-4663-7026], Howey, Lucy A [0000-0001-7381-4871], Humphries, Nicholas E [0000-0003-3741-1594], Hutchinson, Melanie [0000-0001-7042-0658], Jaine, Fabrice RA [0000-0002-9304-5034], Jorgensen, Salvador J [0000-0002-4331-1648], Kanive, Paul E [0000-0003-2430-6920], Labaja, Jessica [0000-0001-6916-7050], Lana, Fernanda O [0000-0001-7235-069X], Lassauce, Hugo [0000-0001-9636-6522], Lipscombe, Rebecca S [0000-0001-9602-643X], Llewellyn, Fiona [0000-0003-4309-8311], Macena, Bruno CL [0000-0001-5010-8560], McCully Phillips, Sophy R [0000-0003-3110-5916], McGregor, Frazer [0000-0002-7441-4404], McMillan, Matthew N [0000-0001-6348-184X], Mendonça, Sibele A [0000-0002-1981-5950], Mohan, John A [0000-0002-2758-163X], Mucientes, Gonzalo [0000-0001-6650-3020], Musyl, Michael K [0000-0003-4719-9259], Nasby-Lucas, Nicole [0000-0001-8355-9392], Natanson, Lisa J [0000-0002-2903-6037], O'Sullivan, John B [0000-0002-1689-2141], Oliveira, Paulo [0000-0001-7697-2111], Papastamtiou, Yannis P [0000-0002-6091-6841], Patterson, Toby A [0000-0002-7150-9205], Pierce, Simon J [0000-0002-9375-5175], Queiroz, Nuno [0000-0002-3860-7356], Radford, Craig A [0000-0001-7949-9497], Richardson, Andy J [0000-0003-2598-5080], Richardson, Anthony J [0000-0002-9289-7366], Righton, David [0000-0001-8643-3672], Rohner, Christoph A [0000-0001-8760-8972], Royer, Mark A [0000-0002-6938-7536], Schaber, Matthias [0000-0003-1032-4626], Schallert, Robert J [0000-0002-3584-2668], Scholl, Michael C [0000-0002-6014-1759], Semmens, Jayson M [0000-0003-1742-6692], Setyawan, Edy [0000-0001-6629-5997], Shea, Brendan D [0000-0001-7771-0586], Shillinger, George L [0000-0001-5168-4551], Shipley, Oliver N [0000-0001-5163-3471], Sianipar, Abraham B [0000-0003-4049-3893], Silva, Joana F [0000-0002-2897-1410], Sims, David W [0000-0002-0916-7363], Sousa, Lara L [0000-0002-4392-3572], Southall, Emily J [0000-0001-7246-278X], Spaet, Julia LY [0000-0001-8703-1472], Stevens, Guy [0000-0002-2056-9830], Sulikowski, James A [0000-0002-3646-5200], Thums, Michele [0000-0002-8669-8440], Tickler, David [0000-0001-7722-0771], Tolloti, Mariana T [0000-0001-6895-2479], Townsend, Kathy A [0000-0002-2581-2158], Travassos, Paulo [0000-0001-8667-5292], Tyminski, John P [0000-0001-8251-7385], Vaudo, Jeremy J [0000-0002-6826-3822], Veras, Drausio [0000-0001-5627-6848], Wantiez, Laurent [0000-0001-5024-2057], Weber, Sam B [0000-0003-1447-4082], Wells, RJ David [0000-0002-1306-0614], Weng, Kevin C [0000-0002-7069-7152], Wetherbee, Bradley M [0000-0002-3753-8950], Williamson, Jane E [0000-0003-3627-4508], Witt, Matthew J [0000-0002-9498-5378], Zilliacus, Kelly [0000-0001-9166-5611], Block, Barbara A [0000-0001-5181-3616], Curnick, David J [0000-0002-3093-1282], Apollo - University of Cambridge Repository, Zoological Society of London - ZSL (UNITED KINGDOM), Centre de recherches insulaires et observatoire de l'environnement (CRIOBE), Université de Perpignan Via Domitia (UPVD)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), MARine Biodiversity Exploitation and Conservation (UMR MARBEC), and Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)

Subjects
Multidisciplinary, [SDV]Life Sciences [q-bio], Violacea Bonaparte, 3103 Ecology, Pelagic stingray, Scalloped hammerhead shark, 41 Environmental Sciences, Western North Pacific, Reproductive-biology, Habitat Use, Carcharhinus-falciformis, Galeocerdo-cuvier, Sexual segregation, Sphyna-lewini, 31 Biological Sciences
Abstract

20 pages, 3 tables, 5 figures.-- Samantha Andrzejaczek ... et al.-- Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC), Knowledge of the three-dimensional movement patterns of elasmobranchs is vital to understand their ecological roles and exposure to anthropogenic pressures. To date, comparative studies among species at global scales have mostly focused on horizontal movements. Our study addresses the knowledge gap of vertical movements by compiling the first global synthesis of vertical habitat use by elasmobranchs from data obtained by deployment of 989 biotelemetry tags on 38 elasmobranch species. Elasmobranchs displayed high intra- and interspecific variability in vertical movement patterns. Substantial vertical overlap was observed for many epipelagic elasmobranchs, indicating an increased likelihood to display spatial overlap, biologically interact, and share similar risk to anthropogenic threats that vary on a vertical gradient. We highlight the critical next steps toward incorporating vertical movement into global management and monitoring strategies for elasmobranchs, emphasizing the need to address geographic and taxonomic biases in deployments and to concurrently consider both horizontal and vertical movements, Data analysis was funded by the Bertarelli Foundation through the Marine Science program through grants to D.J.C., B.A.B., and S.A. D.J.C. is also funded through Research England, UK. S.A. and B.A.B. thank the Moore Foundation and the Packard Foundation. F.G.-M. thanks the Instituto Politecnico Nacional for fellowships (COFAA, EDI). S.B.W. thanks funding from the Darwin Initiative (DPLUS046). A.D.M.D. acknowledges funding from the Research and Conservation Budget at Georgia Aquarium, including philanthropic gifts from several anonymous donors. K.F. acknowledges funding from the Rolex Awards for Enterprise and the Whitley Fund for Nature

Published
2022
Full Text
View/download PDF

3. Residency and Use of an Important Nursery Habitat, Raja Ampat’s Wayag Lagoon, by Juvenile Reef Manta Rays (Mobula alfredi)

Author

Edy Setyawan, Mark V. Erdmann, Ronald Mambrasar, Abdi W. Hasan, Abraham B. Sianipar, Rochelle Constantine, Ben C. Stevenson, and Fabrice R. A. Jaine

Subjects
Global and Planetary Change, Ocean Engineering, Aquatic Science, Oceanography, Water Science and Technology
Abstract

The behaviour and spatial use patterns of juvenile manta rays within their critical nursery habitats remain largely undocumented. Here, we report on the horizontal movements and residency of juvenile reef manta rays (Mobula alfredi) at a recently discovered nursery site in the Wayag lagoon, Raja Ampat, Indonesia. Using a multi-disciplinary approach, we provide further corroborative evidence that the lagoon serves as an important M. alfredi nursery. A total of 34 juvenile rays were photo-identified from 47 sightings in the sheltered nursery between 2013–2021. Five (14.7%) of these individuals were resighted for at least 486 days (~1.3 years), including two juveniles resighted after 641 and 649 days (~1.7 years), still using the nursery. Visually estimated (n=34) disc widths (DW) of juveniles using the nursery site ranged from 150–240 cm (mean ± SD: 199 ± 19), and the DW of two juveniles measured using drones were 218 and 219 cm. Five juveniles were tracked using GPS-enabled satellite transmitters for 12–69 days (mean ± SD: 37 ± 22) in 2015 and 2017, and nine juveniles were tracked using passive acoustic transmitters for 69–439 days (mean ± SD: 182 ± 109) from May 2019–September 2021. Satellite-tracked individuals exhibited restricted movements within Wayag lagoon. The minimum core activity space (50% Utilisation Distribution-UD) estimated for these five individuals ranged from 1.1–181.8 km2 and the extent of activity space (95% UD) between 5.3–1,195.4 km2 in area. All acoustically tagged individuals displayed high residency within the nursery area, with no acoustic detections recorded outside the lagoon in the broader Raja Ampat region. These juveniles were detected by receivers in the lagoon throughout the 24 h diel cycle, with more detections recorded at night and different patterns of spatial use of the lagoon between day and night. The observed long-term residency of juvenile M. alfredi provides further compelling evidence that the Wayag lagoon is an important nursery area for this globally vulnerable species. These important findings have been used to underpin the formulation of management strategies to specifically protect the Wayag lagoon, which will be instrumental for the survival and recovery of M. alfredi populations in Raja Ampat region.

Published
2022
Full Text
View/download PDF

4. The Bird's Head Seascape Marine Protected Area network—Preventing biodiversity and ecosystem service loss amidst rapid change in Papua, Indonesia

Author

Nugraha Maulana, Mulyadi, Irman Rumengan, Syafri Tuharea, Dominic A. Andradi-Brown, Sangeeta Mangubhai, Helen E. Fox, Dariani Matualage, Muhammad E. Lazuardi, La Hamid, Gabby N. Ahmadia, Purwanto, Defy N. Pada, Fitryanti Pakiding, Awaludinnoer, Amkieltiela, Ronald Mambrasar, Nur Ismu Hidayat, and Matt Fox

Subjects
Seascape, geography, mangrove, geography.geographical_feature_category, biology, Ecology, Biodiversity, effectiveness, General. Including nature conservation, geographical distribution, Coral reef, fish biomass, QH1-199.5, biology.organism_classification, Head (geology), Ecosystem services, Fishery, Seagrass, Indonesia, General Earth and Planetary Sciences, coral reef, Marine protected area, Mangrove, management, QH540-549.5, General Environmental Science
Abstract

The Bird's Head Seascape (BHS), Papua, Indonesia is located within the epicenter of global marine biodiversity and has been the focus of recent conservation efforts to protect marine resources. Here, we provide an overview of Marine Protected Areas (MPAs) progress in the BHS over the past decade, including establishment history, changes in management effectiveness and ecosystem health, as well as examining trends in tourism growth. While generally viewed as a conservation success story, we reflect on both successes and challenges in the BHS, identifying where we need to continue to improve and adapt in response to rapid economic and environmental change. As of 2020, BHS MPAs cover 5.1 million ha across 23 MPAs. As expected, management effectiveness is steadily increasing in BHS MPAs—although newer MPAs face substantial capacity gaps. Tourism is rapidly growing—with an almost 3,000% increase in tourist visits between 2007 and 2018. Overall, hard coral cover in monitored BHS MPAs remained stable at 33% from 2010 to 2019, although trends in reef fish biomass were more variable. Given continued conservation challenges in the region, BHS MPAs are successfully preventing biodiversity loss while providing ecosystem services for local communities.

Published
2021

5. A holistic approach to manta ray conservation in the Papuan Bird’s Head Seascape: Resounding success, ongoing challenges

Author

Edy Setyawan, Mark Erdmann, Nikka Gunadharma, Tiene Gunawan, Abdi Hasan, Muhamad Izuan, Meidiarti Kasmidi, Yusdi Lamatenggo, Sarah Lewis, Nugraha Maulana, Ronald Mambrasar, Meity Mongdong, Alberth Nebore, Mochamad Iqbal Herwata Putra, Abraham Sianipar, Kristian Thebu, Syafri Tuharea, and Rochelle Constantine

Subjects
Economics and Econometrics, Management, Monitoring, Policy and Law, Aquatic Science, Law, General Environmental Science
Published
2022
Full Text
View/download PDF

6. Site fidelity and movement patterns of reef manta rays (Mobula alfredi: Mobulidae) using passive acoustic telemetry in northern Raja Ampat, Indonesia

Author

James A. Haddy, Edy Setyawan, Andrew M. Fischer, Ronald Mambrasar, Sarah Lewis, Abraham B. Sianipar, Calvin S. Beale, and Mark V. Erdmann

Subjects
0106 biological sciences, Eagle, Raja, Population, tagging, 010603 evolutionary biology, 01 natural sciences, reef manta, biology.animal, Earth and Planetary Sciences (miscellaneous), West Papua, education, Reef, Nature and Landscape Conservation, Marine Protected Area, education.field_of_study, geography.geographical_feature_category, Ecology, biology, 010604 marine biology & hydrobiology, lcsh:Geography. Anthropology. Recreation, biology.organism_classification, Agricultural and Biological Sciences (miscellaneous), seasonal movement, Fishery, Geography, lcsh:G, Ridge, Archipelago, Mobula, Marine protected area, management
Abstract

Though extremely valuable to the local marine tourism industry, there is a dearth of published information on the ecology and population dynamics of reef manta rays (Mobula alfredi) in Raja Ampat, West Papua, Indonesia. Knowledge of the movement ecology in particular of this large and scattered population is urgently needed to better manage the rapidly expanding manta-focused tourism. Here we report the results of an initial passive acoustic telemetry study designed to provide local managers with the first detailed knowledge of the site use and movement patterns of reef mantas in northern Raja Ampat. A total of 39 reef mantas were tagged with Vemco V16 acoustic transmitters over a 15-month period between 27 November 2013 and 22 February 2015. To monitor their movements, VR2W acoustic receivers were deployed at eight sites corresponding to known manta cleaning and feeding aggregation sites, with receivers downloaded every six months over a two-year initial monitoring period. The duration between tag deployments and last date of detections at sites ranged from 1 to 682 days (mean ± SE = 237 ± 27). The cumulative number of days of manta detections at receiver sites by individual mantas ranged from 1 to 188 days (mean ± SE = 42 ± 7). Manta Ridge was the most visited site with 565 days of detections. The tagged mantas demonstrated strong site fidelity to the observed aggregation sites. At the same time, they also exhibited seasonal movements within an approximately 150 km long corridor between sites in the Dampier Strait and the northwest of Waigeo Island. Data analysed from a nearby array of six VR2W receivers in southern Raja Ampat (approximately 180 km to the south of the study area) confirmed that none of the tagged mantas were detected in this array, providing further evidence of strong site fidelity and limited movements within northern Raja Ampat. More than 96% of detections occurred during the daytime. The number of detections reached a peak around noon at Yefnabi Kecil and Eagle Rock and slightly earlier at Manta Ridge. These findings have been shared with the Raja Ampat Marine Protected Area Management Authority and are now being used in the formulation of a management plan for this vulnerable and economically important species to ensure the long-term health of Raja Ampat's reef mantas and the sustainability of manta tourism in the region.

Published
2018

Catalog

Books, media, physical & digital resources
See catalog results