According to this documentary, mermaids are fully-aquatic species of carnivorous apes that feeds mainly on fish and crustaceans. If mermaids were real, what will happen to them if people disappeared?
Life After People
1 second after people
1 day after people
Power grids failed.
1 year after people
Mermaid populations in Pacific oceans, Atlantic oceans, and the Indian oceans have started to recover due to lack of humans causing climate changes.
500,000 years after people
Mermaids have finally fully recovered due to lack of humans altering the environments around them. They now reach the populations up to 2 million in the Indian oceans, 3 million in the Atlantic oceans, and 4 million in the Pacific oceans like they did during the last Ice Age.