Canadian troops have officially started taking over from their American allies on the front lines of Kandahar province in Afghanistan.

Up until this point, the U.S. Task Force Gun Devils have been heading the military presence in the southern region of the country. But it will now be controlled by soldiers from the Princess Patricia's Canadian Light Infantry.

The handover will be completed next week, but at the first of several ceremonies to be held, the head of the U.S. forces in the region gave his Canadian counterparts an ominous order.

"When the enemy rears its ugly head, I expect you to kill and capture them and defeat them," Lt.-Col Bert Ges, the head of the Task Force Gun Devil told the Canadian troops. "Keep up the aggressiveness and continue on the fight against the enemy."

"The change today is similar to a line change in hockey," Ges said. "It's still the same team going down the ice ready to score, just a different capability out there."

No one in Afghanistan is underestimating the unpredictability of this mission, particularly Capt. Slade Lerch. For the past seven months he's been embedded with U.S. forces.

He has lost friends in the line of duty, and he knows firsthand what his fellow Canadian soldiers are up against.

"The most important thing to realize is that it's not peacekeeping," Lerch told CTV News. "There's people out there who are going to try and kill them because they are Westerners."

Roadside bombs and a vicious insurgency have claimed the lives of almost 300 American troops in Afghanistan. Eight Canadian soldiers and a senior diplomat have also been killed since Sept. 11, 2001.

"I can understand to a certain degree that there is trepidation because of the type of environment that we're in," Maj. Nick Grimshaw told CTV News. "But you have to remember that Canadians have been in war zones for many, many years."

Top soldier responds to poll

Meanwhile in Ottawa, Canada's top soldier responded to a poll showing most Canadians are uneasy about the mission in Afghanistan.

"I wasn't surprised by the numbers," Gen. Rick Hillier told reporters. "I've always felt that we needed to energize, and continually be explaining and helping Canadians understand the mission in Afghanistan, and missions that we do around the rest of the world in places like, potentially Afghanistan."

In the exclusive poll for CTV News and The Globe and Mail, The Strategic Counsel asked Canadians if they would vote in favour or against sending troops to Afghanistan. Just 27 per cent were in favour and 62 per cent were against.

Furthermore, 73 per cent of respondents said the decision to send troops to Afghanistan should require parliamentary approval, while 20 per cent said it should not.

"It indicates that we have a significant challenge," Hillier said. "The numbers indicate that Canadians also believe we have a significant international role to play."

The Canadian troops will be led by Lt.-Col. Ian Hope, who said he still believes Canadians support the Afghanistan mission, despite the danger they will face in the country.

"The average Canadian, regardless about what he feels about Afghanistan and geopolitics, is actually supporting Canadian troops and I am convinced that will be sustained," Hope told reporters on Friday.

Canadian soldiers have been in Kandahar for weeks. By early March, approximately 2,200 Canadian troops will have been deployed to the volatile region.

Friday's ceremony is the first in a number of transitions that will end next week when Canadian Brig.-Gen David Fraser is installed as the head of coalition forces in southern Afghanistan.

Brig.-Gen Fraser will be commanding British, Dutch, and U.S. contingents in three provinces around Kandahar.

All of the troops will fall under the American umbrella of Operation Enduring Freedom. NATO is expected to take over in the southern region in the summer. NATO already looks after the efforts in the northern and western parts of the country.

With a report from CTV's Lisa LaFlamme and files from The Canadian Press