Suspended particulate matter is a key factor shaping the spatial arrangement of Micropogonias furnieri (sciaenidae) population in a Southwestern Atlantic temperate estuary

Abstract

The relative influence of suspended particulate matter (SPM), sea surface temperature, depth, and type of bottom sediment in the spatial distribution of the Micropogonias furnieri (Sciaenidae) population structure was studied in the Río de la Plata estuary. Eight size-assemblages were defined (Cluster Analysis) showing a significant association with environmental variables. The application of the Boosted Regression Trees model for presence/absence and relative abundance showed that the SPM (46.24% and 34.24%, respectively), followed by the depth (31.47% and 33.50%, respectively) were the most important environmental variable in predicting the spatial distribution. Results showed a population segregation pattern. Juvenile and small adolescent fish increased their probability of occurrence and their relative abundance with increments of SPM and decrease of depth. The large adolescent and adult fish substantially increased their occurrence and relative abundance with the decreasing of SPM concentrations at low values. This study quantified and showed the high importance of the SPM in the spatial distribution pattern of the population structure of an estuarine species. In this context, it proposed that the SPM in the Río de la Plata could be used as an indicator of habitat availability of juveniles/adults within an ecosystem approach for fisheries management.