Hábitos alimentares do Caranguejo Scylla serrata capturado no mangal e no Estuário dos Bons Sinais

Abstract

This study investigated the feeding habits of Scylla serrata captured in the mangrove and the Bons Sinais Estuary, aiming to identify and compare diet composition between environments, sexes, and maturation stages. The stomach contents of 93 individuals were analyzed, 50 from the mangrove and 43 from the estuary, collected between August 2024 and July 2025. Stomach repletion was classified using a point system, and food items were identified through microscopic analysis and quantified by frequency of occurrence and food importance index. Common items were identified in both habitats, such as bivalves, fish, shrimp, sand, plant and animal debris, phytoplankton, crab, cnidarians, and eggs. The difference was that amphioxus, echinoderms, copepods, and chaetognaths were recorded exclusively in the diet of individuals captured in the estuary. Based on frequency of occurrence, the items contributing most to the diet of individuals in the mangrove were bivalves (44%) and plant debris and fish (42%), while in the estuary shrimp (69.77%) and fish (65.12%) were the most frequent. Statistical analysis revealed significant differences in diet composition between the environments (p < 0.05), confirming that Scylla serrata adjusts its diet according to the habitat it occupies. No significant differences were found based on sex or stage of maturation (p > 0.05). The Jaccard similarity index (0.714) indicated a high overlap in the types of items consumed between the two habitats, indicating that despite the difference in total contribution, the types of food identified in the stomachs of crabs in both the mangrove and the estuary are common in 71.4%, due to the fact that amphioxus, echinoderms, copepods, and chaetognaths were predominant only in the diet of individuals captured in the estuary.