Reproductive biology of the lane snapper, Lutjanus synagris (Linnaeus 1758) (Perciformes, Lutjanidae), in the Maranhao continental shelf, Northeast of Brazil

To clarify the reproductive activity of lane snapper, Lutjanus synagris, a total of 359 specimens of lane snapper were collected in partnership with an artisanal fleet monitored in a fishing area in the Maranhao continental shelf between May 2018 and June 2019 and verified frequency of size and sex ratio, length/weight ratio (LWR), spawning season, fecundity, and size at maturity. The sex ratio for TL classes significantly deviated for females when the TL was between 36 and 39.9 cm (chi(2) = 12.46; df = 1; p < 0.05). The monthly frequency of maturation stages for females and males showed a high prevalence of individuals in the development stage. Many post-ovulatory follicles indicated that the ovaries developed a reproductive peak before the spawning season. The estimated average length of first sexual maturity (L-50) for grouped sexes was 27.8 cm total length, and the length at which all the individuals were mature (L-100) was 42.0 cm. The temporal variation of the reproductive period is associated with two periods of seasonality in the Maranhao continental shelf, intensifying their reproductive strategies. The understanding of the biological aspects of L. synagris in the Maranhao continental shelf shows that this stock is possibly not yet overexploited. However, responses to fishing pressure can be expected, whether the structure of the stock changes with its intensity. This observation will be useful for the sustainable management and conservation of this species in the study area.

Automated summary

This study investigated the reproductive activity of the lane snapper in the Maranhao continental shelf. The results showed a deviation in the sex ratio and a clear seasonality in the reproductive period. The findings suggest that the stock of this species may not yet be overexploited, but fishing pressure could impact its population.