National Geographic-Lindblad Expeditions is slightly increasing its berth count and bringing operational costs down in Alaska with the charter of the Greg Mortimer.

Cruise Industry News estimates that the company will approximately 30 additional berths in the region with the introduction of the newer expedition vessel, while at the same time, retiring two older, smaller ships.

Those two ships also have a U.S. crew and fly the American flag, while the Greg Moritmer has an international crew and one set of fixed costs.

Starting in 2027, the Greg Mortimer will replace two smaller ships that are being retired: the National Geographic Sea Lion and the National Geographic Sea Bird.

The U.S.-flagged sister ships were originally built in the early 1980s and can carry up to 62 passengers each, according to data from the .

Part of SunStone’s Infinity series, the Greg Mortimer was built at a shipyard in China and entered service in late 2019.

Designed for expedition cruising, the 8,000-ton vessel carries 160 guests in double occupancy and offers modern features, including the X-Bow, which is said to improve efficiency and stability.

Lindblad chartered the Greg Mortimer, which is currently in service for Aurora Expeditions, for three summer seasons starting in 2027.

According to a press release, the ship will offer new itineraries that build on the pioneering legacy of the National Geographic Sea Bird and National Geographic Sea Lion.

The company added that the move supports its “vision to go farther and design new routes that deepen guests’ connection to Alaska’s wildest corners.”

The Greg Mortimer is expected to remain in service for Aurora Expeditions for winter seasons in Antarctica and other destinations.

The Australia-based company also operates two additional Infinity-class ships: the Sylvia Earle and the recently commissioned Douglas Mawson.