Seasonal Evaluation of the Condition Factor in a Surf-Zone Assemblage From Southeastern Brazil

Abstract

The surf zone is a highly dynamic environment subject to seasonal fluctuations which could impose restrictions to the development of juvenile fish. The allometric condition factor index (K) provides a value of 'well-being' for fish, been used to compare populations under different environmental conditions. The aim of this study concerned on evaluate the effect of seasonality on surf-zone juvenile fish' K. Along two years the K values of the main fish species were analyzed. The temperature and abundance were also reported. We compared data between cold and hot seasons to test the effect of seasonality. A total of 955 individuals were collected, totaling 20 species. Despite the surf zone instability, most fish species showed a stable K regardless of season. We found that the condition factor in neritic Atherinella blackburni, Mugil brevirostris, Trachinotus carolinus and Trachinotus goodei did not vary. Only a demersal species, Menticirrhus littoralis, shown the lowest condition factor in the hot season, coinciding with maximum water temperature. We discussed how the surf zone provides conditions for the development of fish and reinforce the importance of this environment as a breeding site.

Surf-zone fish assemblage structure and its diel variability in an ocean beach of Espírito Santo (Central Brazilian coast)

“…Nevertheless, it is relevant to observe that the richness of Guriri Beach is greater than that recorded in other studies using beach seines in different Brazilian ocean beaches [e.g. 22 species in the ocean sector of both Pontal do Sul Beach (Félix 2006) and Peças Island Beach (Stefanoni 2008), southern coast of Brazil; 20 species in Praia Grande Beach, southeastern coast of Brazil (Santos et al 2019)]. However, sample adequacy in such studies was not assessed to determine an eventual undersampling.…”

“…Our study reveals that juveniles of Menticirrhus spp., Trachinotus carolinus, T. goodie, and Polydactylus oligodon dominate the surf-zone fish fauna in the Guriri Beach. The dominance of Menticirrhus spp., T. carolinus, and T. goodie in the surf-zone nekton is a quite common pattern in the central and southeastern coast of Brazil, with such species ranking among the top five in surf fish assemblages (Gaelzer et al 2006, Gaelzer & Zalmon 2008, Félix-Hackradt et al 2010, Gondolo et al 2011, Vasconcellos et al 2011, Del-Favero & Dias 2013, 2015Monteiro-Neto & Prestrelo 2013, Dantas, et al 2016, Costa et al 2017, Santos et al 2019. On the other hand, the great abundance of P. oligodon juveniles found in the Guriri Beach is not quite a common pattern for Brazilian beaches.…”

“…pampos and croackers) that experience comparatively higher growth rates by using abundant stocks of planktonic and benthic prey of the surf zone. Therefore, surf zones are key and strategic habitats in both ecological and economic terms (Defeo et al 2009, Olds et al 2017, Torre et al 2017, Santos et al 2019.…”

Effects of fishing on the Serra Spanish Mackerel (Scomberomorus brasiliensis) in Northeast Brazil

“…This enables monitoring of minimum capture size and size of first maturity (L 50 ) for evaluation of fishing impact on the structural composition of the population over time. Estimating the optimal mesh size enables sustainable fisheries management of target species and associated marine fauna, thereby contributing to overall preservation of sustainable fisheries (Alves et al., 2012).…”