Colossal Claude or Marvin is a sea monster, reported from Mouth of the Columbia River, Oregon, and the neighboring seacoast. Length, 15–40 feet. Round, tan body. Snake- or horselike head. Neck, 8 feet long. Long tail. Raids fishing lines.
In 1934, L. A. Larson, mate of the Columbia River lightship, saw a 40- foot animal at the mouth of the river. Crew members studied it for some time with binoculars.
In 1963, the Shell Oil Company during an oil search off the Oregon coast recorded a videotape that shows a 15-foot animal with barnacled ridges swimming in 180 feet of water.