Abstract

Few quantitative studies of red snapper (Lutjanus campechanus) have been conducted comparing reproductive variables between distinct habitats in the Gulf of Mexico. Reproductive potential is important to fisheries management and can help to determine stock status. Data from previous studies have been largely dependent on red snapper sampled from artificial habitats (AH). This study compares the reproductive potential of red snapper between AH and natural habitats (NH). NHs are areas of vertical relief created from biogenic/geologic processes and are thought to be the historical centers of abundance for red snapper. Red snapper were collected between 2011 and 2013 from three NH sites and two AH sites. The mean gonadosomatic index (GSI) for each habitat was plotted against time to examine seasonal changes in reproductive potential among sites. Results indicate red snapper at NH sites exhibited higher mean GSI than those at AH sites (F = 70.0, p < 0.0001) during peak spawning season. Red snapper at NHs showed 98% maturity, compared to 52% at AHs. Previous studies have shown that red snapper in NHs tend to be shorter and heavier at age, while exhibiting slower growth rates than red snapper in adjacent AHs. These data support the observation of demographic differences in red snapper reproduction between NH and AH. We hypothesize that the difference exhibited is due to red snapper in NHs being in better energetic condition than red snapper in AHs, thus allowing red snapper in NHs to invest more energy in reproduction and less energy towards rapid growth early in life.

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