Stable carbon and nitrogen isotopes in Panulirus argus phyllosomas in the Mexican Caribbean

Abstract

The spiny lobster Panulirus argus (Latreille, 1804) is a commercially important fishery resource in the Caribbean Sea. The complex life cycle of P. argus, particularly during its pelagic life (phyllosoma larvae) is influenced by various oceanographic factors and makes it difficult to develop basic studies about its trophic ecology. The δ13C and δ15N values of the phyllosoma larvae sampled off the SE coast of Quintana Roo, Mexico contributes to assess the migration, feeding and trophic level of the early and intermediate stages of the P. argus life cycle. The δ13C values of the phyllosomas (−18‰ to −22‰) are characteristic of pelagic food resources in oligotrophic oceanic regions, also rich in lipids (ratio C:N 5 to 6). From stage I to IV, the observed δ15N value was enriched by 2.8‰ and remain without change between stages IV and VI, this isotopic equilibrium with the diet was reached between 60 and 70 days of life. The observed enrichment of 15N in P. argus phyllosoma larvae of the Mexican Caribbean suggests a change in trophic level from the early (I–III) to the intermediate stages (IV–VI), during which P. argus larvae remain feeding at the same trophic level.