Hard Bottom Macrobenthos of Chilean Patagonia: Emphasis on Conservation of Sublitoral Invertebrate and Algal Forests

Abstract

The region of the fjords, channels, and islands of Chilean Patagonia (41° 42'S 73° 02'W; 56° 29'S 68° 44'W) has one of the most rugged coasts and is one of the least studied marine systems worldwide. Over the last two decades, we have collected samples (diving down to 35 m) at more than 500 stations, taken underwater photographs, recorded videos from remotely operated vehicles and carried out a comprehensive literature review on benthic (hard bottom) macroinvertebrates and macroalgae. Based on this research, we propose a subdivision of Chilean Patagonia into three biogeographical provinces and 13 ecoregions. The inventory developed indicates the occurrence of rich and extensive sublittoral associations formed by 13 bioengineering species, conforming 11 types of submarine invertebrates, and two types of macroalgal forests. According to the national inventory of wildlife species by conservation status, six of the invertebrate species thriving in Patagonia belong to one of the categories of threatened species. The main local threats to these habitat-forming species are aquaculture, infrastructure and industrialization projects, fishing, and invertebrate harvesting, as well as threats from climate change and volcanic activities. Finally, we identify knowledge gaps and provide recommendations for the protection and conservation of the biodiversity and ecosystem services provided by these species’ associations.