Effects of climate-driven range expansions of tropical snapper species (Lutjanus spp.) on the dominant native species (pinfish, Lagodon rhomboides)

A significant effect of climate change on ecological communities is poleward shifts in species distributions. However, few studies have investigated the impacts of these shifts on endemic communities. Recently, abundances of tropically-associated gray snapper (Lutjanus griseus) and lane snapper ( Lutjanus syngaris) have increased in the northern Gulf of Mexico (GOM), concurrent with regional increases in sea surface temperatures. This study investigated the effects of these species on abundance and growth of juvenile pinfish (Lagodon rhomboides), using a multiple before-after control-impact (MBACI) design. Pinfish abundances were calculated from trawl surveys and daily growth rates were calculated using otolith microstructure analysis. The results of t-tests and analysis of variance (ANOVA) revealed no significant difference in pinfish abundance or growth when snapper were present, compared to when snapper were absent. We conclude that climate-driven shifts of tropically-associated gray and lane snapper have had no significant effect on juvenile pinfish in the northern GOM.