There are new calls to make it mandatory for every ship travelling in Canada's Arctic waterways to report to Canadian authorities.

Right now it is only voluntary for vessels — including cruise, mining and resupply ships — to register with the Canadian Coast Guard's vessel traffic system in the Arctic.

The system helps keep track of ships in case the coast guard has to respond to emergencies.

About 99 per cent of vessels that travel in Arctic waters do enroll in the system known as NORDREG, said Jean-Pierre Lehnert, who is in charge of the coast guard's Marine Communication Traffic Services Centre in Iqaluit.

But, he added, there is no way to be sure.

"What we don't know, we don't know," Lehnert told CBC News.

"Last year, we had the experience of a couple of cruise ships that came into Canadian waters and that did not report to NORDREG. They were coming from Greenland — the [MS] Hanseatic, and the [MS] Bremen."

Lehnert said the ships came and left within a few hours and said "this wouldn't happen" if registration were compulsory.

Senate issues report

In June, a report from the Senate 's standing committee on fisheries and oceans called for a mandatory ship registration system in Arctic waters, as is already the case on Canada's Atlantic and Pacific coasts.

"We need something that duplicates our facilities on the East Coast and the West Coast — we need those duplicated in the Arctic," Newfoundland and Labrador Sen. William Rompkey, who chairs the committee, told CBC News shortly after the report came out.

Lehnert said the senate committee is not alone in wanting to make ship registration required.

"Transport Canada is also proposing to make the reporting of ship information in the Arctic waters mandatory," Lehnert said.

The senate's view is also shared by the Nunavut Impact Review Board, which conducts environmental assessments of development being proposed in the territory.

"Nunavut's a very, very large, very vast territory, and the marine waters are vast as well," said Ryan Barry, a technical advisor with the board.

"So are there potentially cruise ships or other ships coming in that people aren't aware about? I think there's potential for that."

Barry said the majority of ships currently in Arctic waters are responsible, but he added there may be, with a small number of ships, the potential for accidents or problems.