Spatio‐temporal distribution of mutton snapper and dog snapper spawning aggregations in the South‐west Atlantic

Abstract

1. Sites and periods of spawning aggregations of two important fishery resources, the mutton snapper, Lutjanus analis, and the dog snapper, Lutjanus jocu, were identified and validated along the Brazilian north-east coast (latitude 8-15 S) using exploratory analysis of catch per unit effort (CPUE) data, gonadosomatic index analysis, and gonad histology.2. The CPUE analysis for both species allowed the identification of outliers and far outliers, representing fisheries with exceptional catches, which were used as proxies of possible aggregation.3. The presence of pre-spawning and recent spawning signs (hydrated oocytes and post-ovulatory follicles) in the ovary of females caught at sites with recurrent records of high CPUE allowed the validation of spawning activity at those specific sites for each species. All aggregation sites identified in this study were located on

Low population genetic structure is consistent with high habitat connectivity in a commercially important fish species (Lutjanus jocu)

“…Therefore, it is likely that the larvae are capable of longdistance movement with oceanic currents, thereby maintaining the genetic connectivity. In addition, L. jocu forms large spawning aggregations throughout its range (Claro and Lindeman 2003;Heyman and Kjerfve 2008;Biggs and Nemeth 2014), including in Brazil (França and Olavo 2015;Bezerra et al 2021;França et al 2021). Wide-spread movement of adults to spawning aggregations will also contribute to genetic homogenization.…”