Mermaids are believed to be aquatic creatures, hence their legendary diet likely consists of shellfish. Protein sources include lobster, fish, crabs, shrimp, oysters, and clams. Seaweed could be another food that they consume.
Mermaids are frequently pictured inhabiting caves or submerged castles due to their aquatic habitat. Many authors who write about mermaids never specify what they consume. Their food preferences are probably governed by the marine species unique to their living location.
Some people believe that these half-human, half-fish creatures are evil, deceitful beings, while others believe they are benign and playful. Mermaids are supernatural beings, thus each individual’s imagination can determine what mermaids consume and how they live.