Seasonal and interpopulational variability in fecundity, egg size, and elemental composition (CHN) of eggs and larvae in a grapsoid crab, Chasmagnathus granulatus

Abstract

Reproductive traits at the beginning and the end of the annual reproductive season were compared between two populations of the intertidal crab Chasmagnathus granulatus living in ecologically contrasting habitats: (1) Mar Chiquita (MC) (37°45ЈS, 57°19ЈW), a highly productive estuarine coastal lagoon with strong salinity Xuctuations.(2) San Antonio Bay (SA) (40°46ЈS, 64°50Ј), a physically stable but less productive coastal marine environment. Number, size, and elemental composition (CHN) of eggs and larvae diVered signiWcantly between populations. Regardless of the season, more but smaller eggs and larvae were produced in MC, while eggs and larvae from SA revealed higher dry mass and C/N ratios indicating higher lipid content. A latitudinal temperature gradient cannot explain these patterns, suggesting that other environmental factors including salinity, quality or quantity of benthic food sources and productivity may be responsible. In both populations, fecundity and biomass per egg were higher at the beginning as compared to the end of the reproductive season. As a consequence, the reproductive eVort was consistently maximal at the beginning of the season. At MC, also variability was found between two successive years. IntraspeciWc (both interpopulational and seasonal) variations in reproductive and developmental traits may be important for the formation of physiologically diVerent metapopulations along the wide geographic range of C. granulatus.

Great unexpected differences between two populations of the intertidal crab Neohelice granulata inhabiting close but contrasting habitats (Crustacea: Decapoda: Brachyura)

“…This, however, conflicts with morphometric analysis, which did not show a clear geographical pattern of morphological differentiation (although there were some differences among sites) (ituarte et al 2012). Life history traits, activity and feeding differed among several well-studied Argentinean habitats included in the genetic analysis (ituarte et al 2006, Bas et al 2005, 2007, siLva et al 2009, Luppi et al 2013.…”

“…The timing was selected in order to avoid the effect of variations in reproductive parameters during the entire season, which had been previously observed in the population from San Antonio Oeste (Bas et al 2007). Both sites are located in two bays that drain into the much larger San Matias Gulf in northern Patagonia, San José Gulf and San Antonio Bay respectively, and are separated by ca.…”

Inversión reproductiva de Aratus pisonii (Decapoda: Sesarmidae): diferencias entre hábitats y análisis de rutas

“…Los huevos más pesados se observaron en una población donde un temprano incremento en el suministro de alimentos, produjo una anticipada producción de huevos; y sugiere que hubo suficientes nutrientes que se invirtieron en la producción de huevos más pesados. También se ha mencionado que la calidad o cantidad del alimento disponible en cada hábitat, puede causar diferencias en las características reproductivas de poblaciones separadas espacialmente (Kyomo, 2000;Bas, Spivak, & Anger, 2007).…”

“…La variabilidad de patrones de historia de vida en crustáceos decápodos ocurre en respuesta a variaciones de las condiciones ambientales (Conde, & Díaz, 1989b;Mashiko, 1990;Hancock, Hughes, & Bunn, 1998) y por efectos estacionales (Díaz, 1980;Ouellet, & Plante, 2004;Bas, Spivak, & Anger, 2007).…”

“…En los crustáceos decápodos, los aspectos reproductivos mejor estudiados han sido la fecundidad y el esfuerzo reproductivo (Hines, 1982(Hines, , 1991López, Jeri, González, & Rodrí-guez, 1997;Castiglioni, Santos, Reigada, & Negreiros-Fransozo, 2004;Lima, Soares, & Oshiro, 2006;Bas et al, 2007). La fecundidad, tradicionalmente definida como el número de huevos liberados por una hembra por desove, o durante un periodo determinado durante su ciclo de vida (Hernáez, 2001), constituye una información valiosa la cual permite estimar el potencial reproductivo de una población y realizar estudios comparativos.…”