On January 25, 2012 the ship began transit to Newport, Oregon and the Hatfield Marine Science Center for operation by Oregon State University.Oceanus and arrived in Newport, Oregon on February 21, 2012 before the March retirement of Wecoma. The ship is intended as an interim replacement for her sister after a National Science Foundation analysis at Oregon State's request of cost-effective operation of a mid-sized vessel over the period of up to ten years before a new ship is available.
Oceanus was built by Peterson Builders of Sturgeon Bay, Wisconsin to a design by John W. Gilbert Associates, Boston, completed 1975 with a mid-life refit in 1994. The ship is 177 feet (54 m) in length by 33 feet (10 m) beam and 17.5 feet (5.3 m) draft powered by a single EMD diesel engine of 3,000 SHP for a cruising speed of 11 knots with a 7,000 nautical mile range. She carries a crew of 12 with capacity for up to 19 project personnel with 1,185 square feet of laboratory space.
She was described by WHOI as "the North Atlantic workhorse of the WHOI-UNOLS fleet" used extensively in Gulf Stream and ocean circulation systems.