Bangi, Helen Grace P.Juinio-Meñez, Marie Antonette2025-03-292023-07-11Bangi, H. G. P., & Juinio-Meñez, M. A. (2023). Feeding and reproductive phenotypic traits of the sea urchin Tripneustes gratilla in seagrass beds impacted by eutrophication. Diversity, 15(7), 843.1424-281810.3390/d15070843https://hdl.handle.net/20.500.14697/202The authors are very grateful to the anonymous reviewers for providing significant comments and suggestions to improve the manuscript. They are also indebted to the following: Rene R. Rollon, for providing advice on seagrass sampling techniques; Symon Dworjanyn, for providing valuable inputs in the earlier version of this manuscript; Marilou San Diego-McGlone, for providing some water quality data in Bolinao; Charissa M. Ferrerra, for the assistance provided on the Ocean Data View mapping software; Ma Josefa R. Pante, for some statistical advice. The authors would like to thank Jay R Gorospe for reviewing and providing valuable suggestions on the revised version of the manuscript, likewise to Lambert Meñez, for critically editing the manuscript, and to Jerwin Baure for additional assistance in copy editing the manuscript. The authors are thankful to Larry Milan, Jack Rengel, Lawrence Ramoran, for assisting the authors in field sampling and laboratory processing of samples. L. Milan, Jan Noelle Rimando and Aphrodite Entoma assisted in laboratory analysis of samples, particularly in gut content analysis.The sea urchin Tripneustes gratilla is a major grazer and is, hence, an excellent key model organism to study to gain a better understanding of responses to changes in its habitat. We investigated whether there are significant variations in the feeding and reproductive phenotypic traits of populations from three seagrass bed sites, with respect to their proximity to fish farms in Bolinao, northwestern Philippines. We established three stations in each of the three sites: the far, the intermediate, and those near the fish farms, and compared the sea urchins’ phenotypic traits and determined whether these were related to seagrass productivity and water parameters. Regardless of the sampling period, adult sea urchins (66.92 ± 0.27 mm test diameter, TD, n = 157) from the areas intermediate and near to the fish farms had significantly lower indices of Aristotle’s lantern, gut contents, gut and gonads, and lower gonad quality (high percentage of unusual black gonads), compared to those from the far stations. Multivariate analysis showed that the smaller feeding structures and gut, lower consumption rates and lower gonad indices and quality of sea urchins in the intermediate and near fish farms were positively related to lower shoot density, leaf production and species diversity, as well as lower water movement in those stations. The larger size of the Aristotle’s lantern in the far stations was not related to food limitations. More importantly, the phenotypic variability in the feeding structures and gonads of sea urchins in the same seagrass bed provides new evidence regarding the sensitivity of this species to environmental factors that may affect variability in food quality.enAquacultureEutrophicationAquatic ecosystemsSea urchinsAquacultureSeagrassesMarine eutrophicationMarine biology--ResearchArticleSDG 14 - Life below waterSDG 6 - Clean water and sanitationSDG 2 - Zero hungersea urchinsaquaculturesea grasseseutrophicationmarine ecologyChallenge 2: Protect and restore ecosystems and biodiversityChallenge 3: Sustainably feed the global populationChallenge 1: Understand and beat marine pollution