When Viking River Cruises placed an order last month for two oceangoing ships for a new brand, Viking Ocean Cruises, it stirred a great deal of talk about the river and ocean cruise markets: how they compare and how they compete.

Former cruise executive Bill Smith, now Virtuoso’s vice president of cruise sales and exclusive product, called Viking’s action a bold move.

“I think it’s a good strategy to capitalize on cross-selling their repeat cruisers onto deep-water ships. There was never that bridge before, between the two,” said Smith, a former senior vice president of sales and marketing at Crystal Cruises.

“I’ve always wondered: What if Crystal did this, or Silversea? They have great past-guest loyalty programs. Would those people cross over? It’s interesting to think about.”

The move marks one of the few times in memory that a river cruise operator has made the jump to deep-water cruising, and it has many in the industry wondering if other river cruise lines might follow.

For Rudi Schreiner, president of Ama Waterways, the answer is no. He said Viking’s Hagen has a “love of blue water and ocean cruising.”

“He was at Royal Viking Line [where he served as CEO] for years,” Schreiner said. “I think that’s one of his dreams. From my side, there’s really not much interest there.”

Bruce Nierenberg, a veteran of both the ocean- and river-cruise industries and now CEO of United Caribbean Lines, agreed.

Hagen, he said, is “one of the few that has had his feet in both places historically. Torstein would probably find [the ocean cruise market] very comfortable. … I can’t see the other river players having that same comfort level.”

Officials from river cruise companies Avalon Waterways and Uniworld Boutique River Cruise Collection were not available for comment last week.

But other industry insiders said it made sense for both river-cruise and ocean lines to eye each other’s markets for possible entry and look to mergers and acquisitions.

Nierenberg, for example, said, “I wouldn’t be surprised at all if one of the big [ocean cruise lines] decided to buy up one of the successful river ventures.”

He said brands such as Viking or Avalon “would fit very well within any of the empires of Royal Caribbean or Carnival.”

Schreiner, on the other hand, said he wasn’t so sure that river cruising would be a good fit for the deep-water cruise companies. While allowing that crossover marketing opportunities exist, he cautioned that the economies of scale are completely different.

“The ocean cruise lines will stay away from the river cruise product,” he predicted. “The numbers are very different. An ocean cruise line like Royal Caribbean [carries] on one [sailing] as many passengers as we put on one ship in an entire season.

“The logistics are a different environment. For me, it’s a very different business model.”

Nierenberg noted the vast differences in hardware.

“From a technical aspect, running ships around the world is a lot more complicated,” Nierenberg said. “Riverboats are barges with an engine on them that act as hotels. People spend a lot more time on a cruise ship than they do on a riverboat.”

Despite such differences, industry executive Jeff Drew said, “Cruise lines are really looking at river cruises as stiff competition.”

A senior vice president of sales at the Great American Steamboat Co. and a former executive at Oceania Cruises, Seabourn and Cunard Line, Drew said the big cruise lines see the river operators as “taking market share.”

“They’ve done an excellent job, and all the cruise lines are starting to notice,” he said.

As for the timing, Virtuoso’s Smith said that Viking Ocean Cruises’ future competitors, such as Oceania and Seabourn, have added capacity in recent years.

“Does traditional cruising need more 800-passenger ships right now?” Smith asked. “That’s a different subject. But Oceania is very successful, and Seabourn is doing great. We’re seeing demand go up and yields go up. I think maybe the timing is right.”

Nierenberg said his sense was that Viking executives were starting to get “some of the financial results that they like” and consequently had the ability to expand their position in the marketplace.

One of the rare examples of a cruise company that had a hand in both river and ocean markets was Peter Deilmann Cruises, which owned and operated eight river-cruise ships and a 513-passenger oceangoing vessel, the Deutschland.

Peter Deilmann Cruises declared insolvency on its river-cruise business at the end of 2009 and exited the market, but its parent company, Reederei Peter Deilmann, still operates the Deutschland.