Exploring Environmental Descriptors Influencing the Distribution of Antarctic Decapod Larvae in the Ross Sea (Antarctica)

Planktonic species in the Southern Ocean are anticipated to undergo significant changes in the near future. To gain a comprehensive understanding of future community compositions, a deeper understanding of the current environmental factors influencing their distribution is essential. However, these dynamics are still not fully elucidated. Various modelling approaches have recently been employed to investigate this relationship. The response curves generated by these algorithms serve as valuable tools to pinpoint the environmental variables most influential in determining the presence, absence, and biogeographic distribution of Antarctic populations. This study specifically examines response curves for the larval stages of two Antarctic decapod species: Chorismus antarcticus (Pfeffer 1887) and Notocrangon antarcticus (Pfeffer 1887). These species were sampled in Terra Nova Bay and the Ross Sea during the third (1987--1988) and fifth (1988--1989) expeditions of the National Antarctic Research Program. The collected data were correlated with environmental descriptors gathered during these campaigns using the RandomForest algorithm. The Antarctic decapod community demonstrates low biodiversity, predominantly comprising species from the Natantia group. The distribution of Natantia, particularly in their larval stage, remains inadequately researched. Currently, the specific environmental variables influencing their distribution are not fully comprehended. This approach holds critical importance for the conservation and management of these organisms. The findings underscore which environmental factors contribute significantly to shaping the ecological niche of decapods, both in their adult and larval phases. Utilizing such algorithms proves invaluable, providing precise assessments of the presence and absence of Antarctic decapods. This, in turn, facilitates future endeavors in sampling, managing, and conserving these unique communities.