Yuckalinda is known to be ferocious and ravenous. Hungry at all times, she will eat anything that comes near her cave, especially sailors who get caught by her large whirlpool. However, if someone were to feed her food, she will pull them out of her whirlpool and into safety.
Yuckalinda is a green snake-like monster with dark green spots on her back. She has messy orange hair, yellow eyes, sharp teeth, and a forked tongue. Despite being female, she has a little bit of facial hair on her chin. It is unknown if she has limbs or not, or what her tail end looks like. By anyone's guess, she's probably conjoined inside her cave.
After escaping from the Sirens, Scrooge McDuck, his nephews, and King Homer reach a whirlpool next to a cliff where Yuckalinda sleeps inside a cave. King Homer warns that they all must stay quiet and not wake her up. However, after Huey ate one of King Blowhard's umma-gumma fruit, he sneezed really loud, awakening Yuckalinda. She pokes her head out of her cave, immediately demanding to know who awakened her. Then, upon seeing the heroes, she delightfully sees them as lunch and drops down to eat them. Huey threw an umma-gumma fruit into her mouth, and she finds it rather delicious, which gives Dewey an idea. By wrapping a bunch of umma-gumma fruit with rope and throwing it at Yuckalinda, she both ate the fruit and pulled their yacht out of the whirlpool's currents and into safety.
Yuckalinda appears again later near the end of the episode, at night when the Time Twister carrying Scrooge and his nephews whirls by her cave. She comes out to see what the noise was while still being sleepy.