Invasion patterns in artificial vs natural marine habitats: peracarids as models at different spatial scales in Southwestern Atlantic

CARLOS E. RUMBOLD; NICOLÁS BATTINI; CLARA GIACHETTI; KAREN CASTRO; SANDRA OBENAT; EVANGELINA SCHWINDT

Puerto Madryn

Conferencia; Xth International Conference of Marine Bioinvasions; 2018

The study of exotic and native species provides important information about the distribution and the ecological impact of exotic species on native communities. In this context, several peracarid species have invaded a large number of environments worldwide, making them as an excellent model to study invasive patterns in marine environments. In the present study we identified and quantified peracarid species in artificial and natural environments of Southwestern Atlantic, to determine the current status of exotic and native species, their seasonal variation and distribution, to understand the general invasion patterns at different spatial scales. Five biofouling samples were collected seasonally from 2016 to 2017 in two ports and natural environments from two biogeographic provinces, exposed to warm- and cold-temperate waters. Replicate samples were collected by hand and scuba diving scraping biofouling assemblages in 0.20 x 0.20 m quadrants. Artificial environment from warm-temperate region showed higher values of exotic and cryptogenic species (n=9) than the natural habitat (n=4), while in the cold-temperate environments no differences were found (n=3-4), and respect to native species only two were registered in both regions. The present study showed a dominance and an increase in the number of cryptogenic and exotic peracarid species in marine environments of Southwestern Atlantic (ca. 50%), with highest number of exotic species in warm-temperate artificial environments and similar values in the rest of the study sites, suggesting that factors such as propagule pressure, temperature, species diversity and the structure of artificial habitats are closely related to these dissimilarities. The analysis of species assemblages together with their regional distribution allows us to discuss the potential invasive pattern in Southwestern Atlantic.