Merggles are a race of aquatic Fraggles who live among the roots and limbs of the Great Tree in the Fraggle Rock episode "Beyond the Pond". Merggles are the Fraggle version of mermen and mermaids -- the lower half of a Merggle's body is a fish's tail.

In "Beyond the Pond", Red Fraggle follows the Great Tree's roots to meet five Merggles:

  • Mermer Merggle (Steve Whitmire): The leader of the Merggles.
  • Merboo Merggle (Kathryn Mullen): A prophetess, and the keeper of the vision.
  • Merkey Merggle (Rob Mills): A gloomy Merggle, who always sees the dark side.
  • Merple Merggle (Nikki Tilroe): A happy Merggle, who always sees the bright side.
  • Mervin Merggle (Jerry Nelson): A Merggle who sells hats. He captures Red, and only agrees to let her go when she agrees to buy two hats.

Red soon discovers that the Knoblies (which are the roots of the Great Tree) are weakened by Kohlrabi Juice. When the Great Tree started to weaken, Red admits to having considered the Knoblies a major mess in the Fraggle Pond causing the Merggles to lock Red up and prepare to leave for a far-off lake. Red was able to convince Mervin to help her get to the Tree in exchange for buying some hats so that she can use it to have Gobo Fraggle, Wembley Fraggle, and Boober Fraggle stop the dumping of the Kohlrabi Juice. The message was received by Mokey Fraggle (when she touched the Knoblies) causing Gobo to dive in to investigate. When he reaches the Merggles, Gobo tells Red that they have ceased the dumping of the Kohlrabi Juice causing Red to be freed. When the other Fraggles learn about the connections between the Great Tree and the Knoblies, the Merggles show up as Mervin asks the Fraggles if anyone wants a hat.