One day before Halloween, environmentalists dressed up in their ghoulish best for a serious cause – they wore costumes of dead waterfowl to show their distain over the latest tailings pond tragedy in northern Alberta.

About two dozen demonstrators outfitted as zombie ducks headed to Old Strathcona's Gazebo Park on Saturday afternoon, saying they intend to make sure the world knows what happened at Syncrude's Mildred Lake Settling Basin earlier this week.

At around 10 p.m. Monday, birds landed on the tailings pond site just north of Fort McMurray. Industry officials say since that time at least 350 of them have been euthanized – a death toll that could continue to climb.

The incident happened just four days after the oil giant was handed a $3 million fine for a similar tragedy that happened two-and-a-half years ago, when 1600 ducks died on one of its sites.

"I don't want distraught, I don't want words, I want action," said protester Jacqueline Fitzgibbon of the reason behind her participation on Saturday.

The group is calling for a moratorium on tailings pond and says it will take that push to the United Nations Climate Change conference, happening in Cancun, Mexico at the end of November.

Duane Good Striker will be there as an ambassador of environmental affairs, and promises to discuss the issue with as many people as possible.

"What we have to say clearly [is] that we have to protect ourselves and the earth together," he said during the demonstration.

One of the most vocal protesters on Saturday was the Sierra Club's Bryn MacDonald – a former oilfield worker who says a value shift needs to take place in the province.

"When my daughter was born it made me look at life considerably different," he said of why he willingly changed from a job that paid $37,000 a month to $2,000.

"They can't stop nature from happening… [I] realized things had to change."

Alberta's minister of Environment says the province is looking to move away from tailings ponds, but can't make that happen overnight.

Government officials assure they are investigating Monday's incident and will roll out new environmental regulations for the oilsands industries in the near future.

The Climate Change conference will start on November 29th, and comes after world leaders failed to come to agree on collective targets in Copenhagen last year.

With Files from Kevin Armstrong