Manatee is a manatee who only appeared in the episode Manatee's Mermaid Rescue!.

Manatee likes mermaids, so Diego decides to read him a story about mermaids. Finding out the Mermaids were in trouble, Manatee and Diego both jump in to rescue them. Using Click, Diego finds out where the mermaids were: the mermaids' city got pushed out of the ocean and onto a giant rock.

On the way, Manatee helps out other sea creatures, just like mermaids would do every day. For example, he used his tail to clear a tube path for dolphins to go through, just like the mermaids.

Once they arrived at Mermaid City, Manatee used Alicia's rescue rope to pull the Mermaids back underwater. Afterwards, Mariana and all the Mermaids thanked him. When Manatee says he wanted to become a mermaid boy, Mariana tells him she and the other Mermaids were manatees before. Manatee asks Mariana if she can transform him into a Mermaid boy for a little while and Mariana obliges. Manatee enjoys being a mermaid boy, but he loves being a manatee more and transforms back afterwards.

Trivia

• Manatee has a tail just like Mariana and the Mermaids.
• Manatee is the second character who became a human, the first was the Mean Magician.
• Manatee has always wanted to be a Mermaid Boy (or a merman).
• Manatee and Diego found out that mermaids used to be manatees.