Complex sentence: Marine otters are found in littoral areas of southwestern South America, close to shore and in the intertidal areas of southern Peru, along the entire coast of Chile, and the extreme southern reaches of Argentina.
Split into simpler sentences: Marine otters are found in littoral areas of southwestern South America. They are found close to shore and in the intertidal areas of southern Peru, along the entire coast of Chile, and the extreme southern reaches of Argentina.