Tamil migrants are making the choice to come to Canada because it is seen as "the easiest mark in the world" for prospective refugees of any background, says Ottawa's former High Commissioner to Sri Lanka.

Martin Collacott says Canada is a generous and giving country, which tends to accept many more refugees than its Western world counterparts.

"We accept about 50 per cent of people who manage to reach our soil and make refugee claims. The average for other countries is around 15 per cent, so your chances of getting accepted in Canada are much greater," Collacott told CTV's Canada AM from Vancouver on Thursday morning.

"And even if you're turned down, the chances are we won't be able to remove you. We remove a few, but we've had people who have been turned down 20 years ago, but are still appealing."

Refugees are given state-funded lawyers, welfare and health care, which leaves the Canadian system as "the Rolls Royce of claiming refugee status," Collacott said.

For Tamil people, Canada is an especially desirable destination because of its large Tamil population and the high-rate of success for Tamil migrants over the years.

"We took 37,000 refugee claimants from Sri Lanka over one 15-year period, more than from any other country in the world," Collacott said.

"Our acceptance rates were much higher. In 2003, for example, Britain accepted 2 per cent of claims from Sri Lankan Tamils; Germany, 4 per cent; Canada, 76 per cent. So, if you can get to Canada to make your claim, it's like winning the lottery."

At present, a cargo ship is making its way towards the B.C. coast and is believed to be carrying hundreds of Tamil migrants.

Canadian authorities confirmed Wednesday that the MV Sun Sea had crossed into Canada's exclusive economic zone and was expected to hit shore within hours.

Dan McLeod, a Vancouver-based immigration lawyer, said the people on board the ship will first have contact with the Canada Border Services Agency, which will confirm the identities of the passengers.

After that, the cases will be handed over to the Immigration and Refugee Board, which will decide whether to release or detain the people in question.

In a recent interview with The Canadian Press, McLeod said that Ottawa has no option but to let the MV Sun Sea land.

"When a person arrives at a Canadian port of entry, that person is entitled to make an application for refugee status, and basically all they have to do is say something along the lines of ‘refugee' or ‘protection' or ‘fear of persecution' in their home country," McLeod said Wednesday.

"Once they are in Canadian waters, they can't be turned back. Legally, we cannot turn them away, and it would be a very bad precedent for Canada to do so."

There have been reports suggesting that the MV Sun Sea could be carrying some members of the Tamil Tigers -- a banned terrorist organization in Canada -- who could be travelling alongside legitimate refugees.

Collacott said the Tamil Tigers have made "particular use of the refugee system to get in their supporters, they have operated a lot of the people-smuggling that got people in over the last 20 years."

"And at one point, the Toronto Police task force estimated there were 8,000 trained Tamil terrorists in Toronto alone, so, it's been used both for just getting people in who wouldn't qualify normally by international standards, but also for getting terrorists into Canada. And it's expected, it's believed that there are quite a few Tamil Tigers, or their supporters, on this ship."

In June 2000, the National Post reported that Toronto police believed up to 8,000 Tamils living in the city held links to Tamil terror groups, including the Tamil Tigers.

The MV Sun Sea is the second-such ship to make its way to Canadian soil since the end of civil war in Sri Lanka in May of last year.

The first ship to arrive was the Ocean Lady which landed in Victoria last October, carrying 76 Tamil men who applied for refugee status.

With files from The Canadian Press