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Spiers L, Frazer TK. Comparison of feeding preferences of herbivorous fishes and the sea urchin Diadema antillarum in Little Cayman. PeerJ 2023; 11:e16264. [PMID: 38025680 PMCID: PMC10656904 DOI: 10.7717/peerj.16264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 09/18/2023] [Indexed: 12/01/2023] Open
Abstract
On Caribbean coral reefs, losses of two key groups of grazers, herbivorous fishes and Diadema antillarum, coincided with dramatic increases in macroalgae, which have contributed to decreases in the resilience of these coral reefs and continued low coral cover. In some locations, herbivorous reef fishes and D. antillarum populations have begun to recover, and reductions in macroalgal cover and abundance have followed. Harder to determine, and perhaps more important, are the combined grazing effects of herbivorous fishes and D. antillarum on the structure of macroalgal communities. Surprisingly few studies have examined the feeding preferences of D. antillarum for different macroalgal species, and there have been even fewer comparative studies between these different herbivore types. Accordingly, a series of in-situ and ex-situ feeding assays involving herbivorous fishes and D. antillarum were used to examine feeding preferences. Ten macrophytes representing palatable and chemically and/or structurally defended species were used in these assays, including nine macroalgae, and one seagrass. All species were eaten by at least one of the herbivores tested, although consumption varied greatly. All herbivores consumed significant portions of two red algae species while avoiding Halimeda tuna, which has both chemical and structural defenses. Herbivorous fishes mostly avoided chemically defended species while D. antillarum consumed less of the structurally defended algae. These results suggest complementarity and redundancy in feeding by these different types of herbivores indicating the most effective macroalgal control and subsequent restoration of degraded coral reefs may depend on the recovery of both herbivorous fishes and D. antillarum.
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Affiliation(s)
- Lindsay Spiers
- Fisheries and Aquatic Sciences Program, School of Forest, Fisheries, and Geomatics Sciences, University of Florida, Gainesville, FL, United States of America
- Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, Marathon, FL, United States of America
| | - Thomas K. Frazer
- Fisheries and Aquatic Sciences Program, School of Forest, Fisheries, and Geomatics Sciences, University of Florida, Gainesville, FL, United States of America
- College of Marine Science, University of South Florida, St. Petersburg, FL, United States of America
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Salvetat J, Bez N, Habasque J, Lebourges-Dhaussy A, Lopes C, Roudaut G, Simier M, Travassos P, Vargas G, Bertrand A. Comprehensive spatial distribution of tropical fish assemblages from multifrequency acoustics and video fulfils the island mass effect framework. Sci Rep 2022; 12:8787. [PMID: 35610249 PMCID: PMC9130204 DOI: 10.1038/s41598-022-12409-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 04/27/2022] [Indexed: 11/22/2022] Open
Abstract
Tropical marine ecosystems are highly biodiverse and provide resources for small-scale fisheries and tourism. However, precise information on fish spatial distribution is lacking, which limits our ability to reconcile exploitation and conservation. We combined acoustics to video observations to provide a comprehensive description of fish distribution in a typical tropical environment, the Fernando de Noronha Archipelago (FNA) off Northeast Brazil. We identified and classified all acoustic echoes into ten fish assemblage and two triggerfish species. This opened up the possibility to relate the different spatial patterns to a series of environmental factors and the level of protection. We provide the first biomass estimation of the black triggerfish Melichthys niger, a key tropical player. By comparing the effects of euphotic and mesophotic reefs we show that more than the depth, the most important feature is the topography with the shelf-break as the most important hotspot. We also complete the portrait of the island mass effect revealing a clear spatial dissymmetry regarding fish distribution. Indeed, while primary productivity is higher downstream, fish concentrate upstream. The comprehensive fish distribution provided by our approach is directly usable to implement scientific-grounded Marine Spatial Planning.
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Affiliation(s)
- Julie Salvetat
- Pós-Graduação em Recursos Pesqueiros e Aquicultura, Universidade Federal Rural de Pernambuco, Rua Dom Manoel de Medeiros, s/n, Dois Irmãos, Recife, PE, 52171-900, Brazil. .,MARBEC, Univ Montpellier, CNRS, IRD, Ifremer, Sète, France. .,Institut de Recherche pour le Développement, Sète, France.
| | - Nicolas Bez
- MARBEC, Univ Montpellier, CNRS, IRD, Ifremer, Sète, France.,Institut de Recherche pour le Développement, Sète, France
| | | | | | - Cristiano Lopes
- Pós-Graduação em Recursos Pesqueiros e Aquicultura, Universidade Federal Rural de Pernambuco, Rua Dom Manoel de Medeiros, s/n, Dois Irmãos, Recife, PE, 52171-900, Brazil
| | | | - Monique Simier
- MARBEC, Univ Montpellier, CNRS, IRD, Ifremer, Sète, France.,Institut de Recherche pour le Développement, Sète, France
| | - Paulo Travassos
- Pós-Graduação em Recursos Pesqueiros e Aquicultura, Universidade Federal Rural de Pernambuco, Rua Dom Manoel de Medeiros, s/n, Dois Irmãos, Recife, PE, 52171-900, Brazil
| | - Gary Vargas
- Pós-Graduação em Recursos Pesqueiros e Aquicultura, Universidade Federal Rural de Pernambuco, Rua Dom Manoel de Medeiros, s/n, Dois Irmãos, Recife, PE, 52171-900, Brazil
| | - Arnaud Bertrand
- Pós-Graduação em Recursos Pesqueiros e Aquicultura, Universidade Federal Rural de Pernambuco, Rua Dom Manoel de Medeiros, s/n, Dois Irmãos, Recife, PE, 52171-900, Brazil.,MARBEC, Univ Montpellier, CNRS, IRD, Ifremer, Sète, France.,Institut de Recherche pour le Développement, Sète, France.,Laboratório de Oceanografia Física Estuarina e Costeira, Depto. Oceanografia, Universidade Federal de Pernambuco, Av. Prof. Moraes Rego, 1235-Cidade Universitária, Recife, PE, 50670-901, Brazil
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