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Influence of temporal and spatial factors on abundance and richness of fish early stages in shallow tropical estuaries

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Abstract

Accurate determination of abundance and richness of fish early stages in estuarine zones is critical to support management and protection plans; it is therefore necessary to consider all influential factors. Habitat diversity, seasonality, moon phase and diel variations, and their interactions are factors that can affect richness and abundance estimations. Appropriate spatial and temporal scales in sampling design are important to understand the assemblage dynamics of fish early stages. The objective of this research is to test how temporal and spatial scales influence the determination of abundance and richness of fish early stages based on a hierarchical sampling design considering season (dry and rainy), moon phase (new, crescent, full, and waning), day period (sunrise, midday, sunset, and night), habitat (coastal, riverine, mangrove, and Vallisneria americana beds), and their interactions. Samples were collected using a conical zooplankton net and towed horizontally for 5 min at a depth of 50 cm. A variance component analyses model showed that day period, season, and their interactions were the main factors determining variations in fish early stage abundances and richness (26.68, 10.78, and 12.82 %, respectively). The highest abundance and richness occurred at night, with significant seasonal variations related to the runoff from the Grijalva-Usumacinta basin. Abundance and richness were higher in the dry season, which were related to higher dissolved oxygen and water transparency. Presented findings can be generalized to tropical and subtropical estuaries with shallow waters.

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Acknowledgments

We thank those who helped us carry out the sampling: Juan Juárez, José Gaspar Calam, and Sofia Santiago, and fishermen who helped with the sampling survey: Benjamín Martínez and Gustavo Salvador. We thank Alejandro Espinoza, Juan Carlos Pérez, and Ana Laura Ibañez for early revisions of this document and for the anonymous reviewers that helped us improve this article. The second author is grateful to CONACYT for a grant that funded a sabbatical stay at the Wageningen University where this paper was finished. Thanks to the aquaculture and fisheries research group at Wageningen University for ongoing support. This project was partially financed by the International Foundation for Science and CONACYT-ECOSUR.

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  1. Manuel Mendoza-Carranza

    Present address: Aquaculture and Fisheries Group, Wageningen University, The Elst 1, 6708 WD,, Wageningen, The Netherlands

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  1. Sustainable Management of Basin and Coastal Zones, El Colegio de la Frontera Sur, Carretera Villahermosa-Reforma km 15.5, Ra. Guineo 2a. sección, C.P. 86280, Villahermosa, Tabasco, Mexico

    Wendi Arévalo-Frías & Manuel Mendoza-Carranza

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Arévalo-Frías, W., Mendoza-Carranza, M. Influence of temporal and spatial factors on abundance and richness of fish early stages in shallow tropical estuaries. Environ Biol Fish 98, 891–904 (2015). https://doi.org/10.1007/s10641-014-0324-x

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