Isotopic enrichment in Rhizoprionodon porosus (Poey, 1861) and Carcharhinus porosus (Ranzani, 1840) embryos

Abstract

Isotopic values of two Caribbean sharpnose shark Rhizoprionodon porosus litters (Poey, 1861) with two and three embryos and one litter of 11 smalltail shark Carcharhinus porosus embryos showed enriched ¹⁵ N and ¹³ C compared to their mothers. In R. porosus, embryonic isotope values were 3.06 ± 0.07‰ and 0.69 ± 0.15‰ greater than their mothers' for δ¹⁵ N and δ¹³ C, respectively, whereas in C. porosus, δ¹⁵ N and δ¹³ C were 1.79 ± 0.09‰ and 1.31 ± 0.17‰ greater in embryos than their mothers.

Keywords: Colombian Caribbean; Gulf of Salamanca; elasmobranch; mother-offspring interaction; stable isotope analysis.