TORONTO - The country's much debated and oft-maligned do-not-call list is proving effective at stopping nuisance phone pitches even though some Canadians are receiving more unwanted calls since registering, a new survey suggests.

The poll, to be released Monday, finds 80 per cent of those on the list said they received fewer calls after putting their numbers on the list, which was implemented Sept. 30.

On the other hand, 13 per cent said the number of telemarketers contacting them had risen to unprecedented levels despite registering, according to the Harris-Decima survey.

The situation is worst in Alberta and British Columbia, where almost one in four people on the list report getting more calls -- double than in Ontario and Quebec.

"The national do-not-call-list is benefiting the great majority of those who've registered a telephone number by stemming unwanted telemarketing calls," Brendan Wycks, executive director of the Marketing Research and Intelligence Association, said Sunday.

"There's no evidence to support the contention that there's a lot of fraudulent use of our national (list) going on."

The federal government put the no-call list in place to deal with perennial complaints about unsolicited sales calls. About 6.2 million Canadians have entered phone numbers on the database (at https://www.lnnte-dncl.gc.ca/).

Telemarketers are legally required to access the list and ensure they do not attempt to contact those numbers.

The results debunk suggestions that large numbers of telemarketers have been buying the list of blocked numbers for cold calling, said Wycks whose association commissioned the survey.

"It just doesn't seem likely that a telemarketing organization would benefit from telephoning a list of people who've expressed a strong desire not to be contacted," he said.

"The national do-not-call list just does not make a good sucker list."

One explanation for why some on the list are getting more calls is an upswing in "rogue" telemarketers using "demon" diallers, which automatically dial huge quantities of phone numbers -- including those on the list.

A recent example has been a surge in calls from the U.S. involved in a car-warranty scam.

"Some of us are being plagued by these rogue telemarketing calls coming out of the U.S," Wycks said.

Some telemarketers -- particularly those in the U.S. -- either don't know or don't care if targets have registered with Canada's list, he said, adding such calls are likely to increase as the recession bites harder south of the border.

Still, Wycks said, Canada's federal regulator should beef up its enforcement activities and try to strike a reciprocal enforcement agreement with its U.S. counterpart.

He also urged Canadians to report inappropriate calls to the Canadian Radio-television and Telecommunications Commission or to Phonebusters.

The association, which regulates Canada's opinion-research industry, commissioned the telephone survey as part of a series in its VoxPop campaign.

In all, 2,035 adults were contacted Jan. 29 to Feb. 15. The poll is considered accurate to within 2.2 percentage points, 19 times out of 20.