Community structure and diversity of five groups of zooplankton in the Perdido region of the Gulf of Mexico using DNA metabarcoding

The evaluation of biodiversity is a primary concern for natural sciences and society, including marine ecosystems. Zooplankton plays a crucial role in marine ecosystems, transferring energy between trophic levels and participating in carbon and nutrient cycling. Zooplankton communities respond to changes in environmental conditions in complex ways and are highly susceptible to anthropogenic impacts, including climate change. However, the study of their diversity relative to environmental conditions has been hindered by their extremely high taxonomic diversity, which requires a high level of specialization for the morphological identification of specific taxa. We used metabarcoding to evaluate the relationship between zooplankton diversity and oceanic conditions along two transects in the Perdido region of the northwestern Gulf of Mexico during the summer and fall of 2016. This area has active oil production and ongoing exploratory wells. We focused on five zooplankton groups: Mollusca, Calanoida, Non-Calanoid copepods, Decapoda, and Amphipoda. We found that the studied groups had different levels of diversity that varied among sampling stations and seasons, and the taxonomic composition had larger differences among stations than between seasons. We found that environmental variables may have influenced the presence of zooplanktonic groups; however, we conclude that it is not possible to generalize deterministic factors that influence zooplankton diversity and that both the spatial and temporal scales are needed to take into account to determine the factors that shape such diversity.