Pearl is one of the Big Harbour's two pilot boats (the other being Petra) who patrol the harbour and sometimes help the tugs with moving ships to their docks. They both used to have a problem with not listening to the tugboats, which caused a lot of confusion.
Pearl was the first pilot boat to come to the the harbour. She expects a little too much from the tugs and can be very strict with them. She used to be taken as mean and boring, until she played a fun game with Theodore.
Both Pearl and Petra are hard working and work together with the tugs to keep the harbour running properly. She can be very proud and stubborn at times, but can move great loads in nimble timing, which what makes her special. And more importantly, she's a great friend of the tugboats in the Big Harbour. 
Pearl can be described as being precise, sharp, and never misses an opportunity to use her whistle.
- Season 1 - The Dark and Scary Cove, Foduck the Vigilant (does not speak), Different Strokes - Different Boats, True Blue Friends, Bumper Buddies, Theodore the Vegetable, Theodore's First Pull, Theodore and the Queen, Is Anybody Listening?, George Buzzes the Dock (cameo), Best Friends, and Theodore and the Big Harbour
- Season 2 - The Tugboat Pledge, Theodore the Tug in Charge, and Foduck and the Rainbow
- Season 3 - Theodore and the Ice Ship, Big Harbor Birthday and Theodore and the Pirate
- Season 4 - George and the Navy Ship, Theodore's Prize and Emily's Bruised Bumper
- Season 5 - Hank Hurts a Ship, Theodore Gets Lost, Hank and the Silly Faces, Bedford's Big Move (does not speak)
- Pearl is the older of the two pilot boats.
- Pearl's model is currently displayed at the Maritime Museum of the Atlantic.
- In the Norwegian version, Pearl is called Lisa.