Another two of Alberta's grizzly bears have been killed.
A mature female grizzly known as Bear #71 and one of her two cubs were hit and killed on the tracks operated by Canadian Pacific Railway on Saturday.
The animals were being tracked by Parks Canada officials.
They say the older animal, Bear #71, was first fitted with a radio-collar in 2001 and then ear tag transmitters in 2007.
She produced three litters of cubs, including a pair of cubs last year.
Both the mother and her yearling male cub were struck and killed on the tracks about three kilometres east of Canmore.
The remaining surviving cub was tranquilized and captured by provincial officials. It will be released back into the wild as far away as possible from human habitation.
Defenders of Wildlife say the CPR has a shameful record operating in Banff National Park and is calling on the company to accelerate its plans to repair faulty grain cars.
The group says grizzlies, elk, and other wildlife are attracted to grain spilled by CPR trains.
But CPR officials say that they are equally frustrated by the animal deaths.
They say spilled grain does not appear to be a factor in either this incident or the previous death of a male grizzly killed by a CPR train earlier this year.
The company says its refurbishment program on its grain cars is 45 per cent complete and it is proactively working on solutions to stop animal mortality on its tracks.
