Canada's canola stockpile swelled to a record high, and wheat supplies were the biggest in 20 years by the end of 2013, Statistics Canada said on Tuesday, after farmers reaped bumper crops.

Huge stockpiles came as no surprise after ideal weather helped farmers produce unprecedented wheat and canola harvests last year that grain handlers and railways have struggled to move to port.

Statscan pegged canola stocks at Dec. 31 at 12.597 million tonnes, up 55 percent year over year, and all-wheat supplies at 28.381 million tonnes, an increase of 38 percent.

The trade, on average, expected canola stocks of 12.3 million tonnes and wheat supplies of 28.9 million tonnes, according to a Reuters survey.

Durum stocks climbed 36 percent to 5.342 million tonnes.

Statscan's estimates looked mostly in line with expectations, said Dave Reimann, market analyst at Cargill Ltd's grain marketing services division.

"The outcome is still the same, that we're going to be facing big (supplies) by the end of July, and it's going to be a plugged pipeline for the months to come," he said.

ICE Canada March canola futures turned slightly lower after the report.

Canada is usually the world's second- or third-largest wheat exporter and the biggest shipper of canola, a cousin of rapeseed used largely to produce vegetable oil.

A backlog of more than 40,000 railway cars since Aug. 1 has resulted in some grain handlers accepting few or no new crop deliveries from farmers until spring.

Farmers who live near the Canada-U.S. border have avoided some of the bottlenecks by transporting crops to buyers in the United States, said Brian Voth, senior market coach at Agri-Trend.

Canola in particular is flowing to U.S. crush plants in Washington and Minnesota, Voth said on a conference call organized by Minneapolis Grain Exchange.

Statistics Canada pegged barley stocks at 6.695 million tonnes, up 27 percent and oat supplies at 2.871 million tonnes, a rise of 40 percent.

Soybeans bucked the trend of a huge increase in supplies. Soy stocks edged up 2.4 percent year over year to 2.65 million tonnes. Stockpiles were limited by the steady flow of soybeans from Ontario and Manitoba into the United States, Voth said. (Additional reporting by Alex Paterson in Ottawa; Editing by Jeffrey Benkoe and Meredith Mazzilli)