Priscilla Bonner was originally cast as Esther because John Barrymore's first choice, his then-love 'Mary Astor (I)', was unavailable. Before filming started he met and fell for Dolores Costello and replaced Bonner with her.
In an interview that appeared in The American Dancer (January 1929), Joyzelle Joyner stated that many times she not only designed but actually made her own costumes. "For instance, the one which caused so much favorable comment when worn in the prologue to 'The Sea Beast.' The dancing was rather exotic, and although she haunted all of the costume houses, Joyzelle could not find a garment that suited the part of the native maiden. Finally, an inspiration struck her, and she rushed out and bought three rolls of clothesline, which she promptly raveled and then dyed, red, green and yellow. The result was a most effective costume especially when combined with the head-dress of real animal horns and feathers. The total cost of the 'ensemble' was $3.00." Unfortunately, the copies of "The Sea Beast" that have survived do not seem to contain the dance prologue featuring Ms. Joyner.
The scenes of the giant whale attacking the ship were created on a California lake, using a miniature ship and a giant rubber whale puppet operated by short people. During the filming of one scene, the whale puppet sank with the puppeteers inside. Members of the film crew had to dive to the bottom of the lake to rescue the puppeteers.
To "doctor" the film, Jack L. Warner enlisted the help of Rupert Hughes, who reedited it and provided new titles. Since no compensation had been agreed upon, Warner sent a check for $1500, which Hughes returned saying he had done the work as a favor to both Warner AND Herman Melville.