Since the association's last revision in January, the number of operating days is expected to decline by an additional 10,320 days, or 13%.

A sharp drop in the number of overall operating days means an estimated reduction of 25,110 total jobs in 2015, down almost 50% from the 2014 total of 49,950.

"Potential policy changes in Alberta with respect to royalties, other factors such as LNG activity in British Columbia and depressed commodity prices, means our members must continue to streamline operations and remain agile," CAODC president Mark Scholz said.

The oil price downturn has been particularly bad for Western Canada, with RBC Capital Markets revealing there are currently 123 active drilling rigs in its Sedimentary Basin, down 54% from the same time last year and 53% under the five-year average.

Alberta's oil sands producers, meanwhile, are also under the pump on the environmental side, as a group of prominent scientists and academics earlier this week called for a moratorium on further development.

In a statement signed by 110 researchers from across North America, the group said the planned growth in oil sands production was inconsistent with efforts to cut greenhouse gas emissions and avert the worst impacts of climate change, and also threatened the ecosystem of a vast stretch of the boreal forest.

Simon Fraser University ecologist Wendy Palen said decisions on oil sands development "add up to a social and environmental legacy that will last for generations".