Volumen 45 - Número 3: 541-546 | 2010
Research Note

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Size composition and sex ratio of Anadara tuberculosa and Anadara similis in a mangrove reserve from the northwest of Ecuador

Luis Flores^1* and Roberto Licandeo²

¹Investigación de Recursos Bioacuáticos y su Ambiente, Instituto Nacional de Pesca, Letamendi 102 y La Ria, P.O. Box 09-01-15131, Guayaquil, Ecuador

²Center for Quantitative Fisheries Ecology, Old Dominion University, 800, West 46th Street, Norfolk, United States of America 

*This email address is being protected from spambots. You need JavaScript enabled to view it. 

Shell length frequency distribution (SLFD) and sex ratio of a subpopulation of the mangrove cockles Anadara tuberculosa and Anadara similis were analyzed from natural beds in the Cayapas-Mataje Ecological Mangrove Reserve, Ecuador. The SLFD was different between sexes for both species; females were larger than males. Subpopulations of A. tuberculosa and A. similis were dominated by females throughout the year. The overall sex ratio was 2.6:1 (female: male), although with variations in the monthly samples, from 1.2:1 to 5.9:1 in A. tuberculosa and 1.9:1 to 5.3:1 in A. similis. Possibly, these results may be due to differential growth rate between sexes and environmental factors along the year.

Key words: Shell length, mangrove cockles, natural beds

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