"For the folks we're looking for, the challenge that they're dealing with is that it is cold water", he told a news conference Tuesday.
The Royal Princess, which can carry up to 3600 people, was among four city-sized cruise ships in the tiny coastal community on the day.
Earlier, the company confirmed that the pilot of a de Havilland DHC-2 Beaver and at least three passengers were killed in the collision with a de Havilland Otter DHC-3 yesterday.
Ten people were being treated at Peace Health's Ketchikan Medical Center.
The de Havilland DHC-2 Beaver floatplane flew off course, despite clear conditions, and nosedived into the Hawkesbury River north of Sydney, killing the pilot and five members of a British family on board.
Two sightseeing planes that crashed in Alaska collided at about the 3,300-foot (1,006-meter) level, the National Transportation Safety Board announced shortly after an elite team arrived Tuesday from Washington, D.C., to investigate the crash.
Local emergency responders worked with state and federal agencies and good Samaritan vessels to help rescue and recover victims.
The Coast Guard, which is leading the investigation, said 10 people were rescued following the collision between a Beaver floatplane and an Otter floatplane.
"We are devastated. and our hearts go out to our passengers and their families", it said in a statement.
Princess Cruises in its release said two passengers and the pilot were among those killed in this plane. She said the ship is not leaving as scheduled and there weren't any details as to how the accident will affect the rest of the trip.
The Royal Princess departed Vancouver last Saturday, and was scheduled to arrive in Anchorage, Alaska, on Saturday May 18.
'We are extending our full support to the investigating authorities as well as the traveling companions of the guests involved, ' the company said in a statement.
"We are deeply saddened to report this news and our thoughts and prayers are with those who lost their lives and the families of those impacted by today's accident".
Larry Vance, a former investigator with the Transportation Safety Board of Canada, said the planes would not have been advised by air-traffic control and instead would have been flying under visual flight rules.
Weather conditions in the area on Monday included high overcast skies with 14 kph southeast winds.
It is not the first time a major plane crash has occurred near Ketchikan, a popular tourist destination. They'd been passengers on an aerial tour of the George Inlet. The cause of the crash was not immediately known.