Grizzly bears are inexorably drawn to grain spilled along railway tracks by trains en route to Vancouver from the Prairies, wildlife experts say. (CBC)

Wildlife and railway experts will be thinking outside the boxcar this winter to come up with ways to reduce the number of grizzly bears that are killed by trains that rumble through the Rocky Mountain national parks straddling the B.C.-Alberta border.

Placing water cannons on trains to squirt bears away from the tracks is the most colourful idea being floated.

But the talks, involving Parks Canada and Canadian Pacific Railway Ltd., are expected to focus on more practical solutions such as fencing off portions of the tracks and building special overpasses so bears can walk over the rail line instead of on it.

It's all part of efforts to cut an unacceptable number of grizzly deaths, particularly among females who are of cub-bearing age, said Bill Hunt, resource conservation manager for Parks Canada in Banff, Yoho and Kootenay national parks.

"We are sitting down this winter with Canadian Pacific to talk through the pros and cons of each of these options and some of them might not be practical," Hunt said.

"The bear population in this part of the country is sensitive to any increase in human-caused mortality. If we can get rid of a fairly significant unnatural cause of death, then that is going to make the bear population that much more viable for future Canadians to enjoy."

A Parks Canada report in May noted at least 63 bears, mainly females, died in the mountain parks between 1990 and 2008. The vast majority of the deaths were related to interaction with humans. Railways are listed as the main cause.

Spilled grain is irresistible

The biggest problem is in Banff National Park, where the number of deaths of independent female grizzlies has exceeded Parks Canada targets for the past seven years.

Why are so many bears dying on the tracks? Experts say one of the main reasons is grain spilled from bulging hopper cars en route to Vancouver from Prairie farms.

Spills of wheat, corn, peas and other grains are irresistible to the hungry omnivores, described as walking stomachs with noses.

Some grizzlies will revisit spill sites again and again, year after year, clawing holes in the rail bed in search of kernels of grain. Once they start eating, they are oblivious to approaching trains.

Since 2007, CP Rail has been working to fix faulty gates on 6,600 grain cars so they won't leak. More than 4,400 cars have been refurbished so far.

The company also uses a special rail vehicle to vacuum spills along the line, said Breanne Feigel, a railway spokeswoman.

Fences, whistles suggested

Parks Canada said dealing with grain spills is important, but it's only part of the solution. Bears and other wildlife are well accustomed to using the tracks as a pathway. CP trains have been running through the area for 125 years.

Fencing off problem areas and building wildlife overpasses are reducing the number of bear deaths on the Trans-Canada Highway through Banff National Park. The same idea could work on the rail line, Hunt said.

Feigel said CP is also looking at blowing train whistles going into curves and perhaps putting high-frequency wildlife whistles on locomotives to shoo the bears away.

As for squirting the grizzlies, Feigel said that idea doesn't hold much water.

"It would take years to implement or even think about," she said. "We have 1,400 locomotives. The water cannon idea would not be considered."