Sabawaelnu, a.k.a. "The Halfway People", "The Water People", are merfolk in the lore of the Micmac peoples of Eastern Canada.
Appearance: Small mermaids or mermen having the upper torso of a human while the lower portion of the body is a fish tail.
Lore: The Halfway people are believed to be peaceful and kind magical beings who love to sing. Only people in tune with the spirit world, as well as the elderly and young, can hear their singing. Sabawaelnu will stop singing right before a storm. This can be used as a warning of approaching bad weather for those who are able to hear the singing of the Halfway people. Halfway people are very curious about humans. Sometimes they will surface next to a boat and ask for a small token from one of the humans. If they are treated kindly then that person will receive very good luck in return for their generosity. If they are disrespected or treated bad then they will raise a storm to sink the boat. Sometimes Sabawaelnu will kidnap children to take with them to either visit or live with them in their underwater realm. In legends this is usually done when the parents or guardian of the child treated them rudely. Sometimes they return the children.
Powers: Sabawaelnu have power to raise storms and can bestow good luck on people who are kind to them and show them respect.
Defense Against Sabawaelnu: The Halfway people are little-to-no threat to good people. When traveling by boat one may want to offer a pinch of tobacco for the Sabawaelnu for protection, good luck, and fair weather.
Trivia: In 1870, a Micmac man claimed to have found an infant Sabawaelnu that had been stranded by low tide on the coast of Nova Scotia. His partner wanted to bury it in the sand but the man knew better. He took the poor creature back to deep water and released it.
The Micmac Indians Of Eastern Canada by Wilson D. Wallis and Ruth Sawtail Wallis
Mysterious Creatures: A Guide To Cryptozoology by George M. Eberhart