Características biométricas e Índices de condição da ostra-do-mangue Crassostrea rhizophorae (Guilding, 1828) do estuário do rio Ipojuca, PE, Brasil

As sessile filters and bioaccumulators, oysters are good indicators of the health of estuaries. Changes in the morphological characteristics of its shells and the weight ratio of its flesh to the volume of its shell, etc. reflect the quality of the environment in which they live. The present work focuses on an evaluation of the conditions of the mangrove oyster Crassostrea rhizophorae in the estuary of the Ipojuca River, one of the most polluted in the country. For this purpose, 80 individuals from 4 areas of the Ipojuca river estuary were collected, in jan/2019 (post-spawning) and oct/2019 (spawning), weighted and measured. Based on these data, the shell thickness indices (STI1) and the AFNOR French standard quality index were calculated. Results revealed, on one hand, the occurrence of oysters commercially classifiable as “fine” and even “specials” in terms of their development and filling of their intervalval space. On the other hand, low values (< 4) of the STI1 monitoring index, a strong TBT contamination indicator, alerts to the need for future investigations to confirm these suspicions as well as to investigate the suitability or otherwise of Ipojuca oysters for human consumption.