As if global growth worries were not enough; natural calamity gnawed at the Canadian economy last week. The country saw the worst wildfire in recent times, with about 400,000 acres bursting into flames. Apart from residents’ safety issues, the outbreak – which took place in Fort McMurray, Alberta – was more detrimental to the oil sands (read: Global Growth Worries Loom: ETFs to Play). The region is oil-rich and economists are now predicting that ‘wildfire could cut oilsands’ production in half’. Among the renowned operators, Suncor Energy (SU) has closed all of its oilsands facilities in the region, causing about 600,000 bbl/d of production stoppage and has surrounded its facilities with fire breaks. The other companies that shut down production included Shell Albian Sands, Nexen Long Lake and ConocoPhillips Surmont and so on. Given uncertainties pertaining to the wildfire situation, Royal Bank of Canada (RBC) commented that “if we assume those shutdowns last for two weeks, they would subtract 0.5 per cent from May GDP." Apart from the blows from oil-related earnings, this unprecedented disruption will also likely weight on citizens’ daily routine and thus take a bite out of retail sales. Economists’ Estimate Cut Owing to this fire issue, RBC has slashed its prediction for second-quarter annualized growth to 0.5%. Previously, the bank had expected Canada's economy to expand at a 1.5% clip in the April-to-June quarter, per the source. BMO Financial has also reduced its second-quarter GDP estimate to zero from 1.5% to account for the damage of the Fort McMurray wildfires. A Nomura economist forecast that a fall of about 500,000 barrels of production per day is equal to nearly one-fifth of overall output. And this would curtail growth by about 0.12 percentage points for every week of production cease. All in all, the Canadian economy is to get a considerable hit by the oil patch as the Fort McMurray has been reduced to ashes and will take some time to get back to its former shape. As per BMO capital, a catastrophe of this level could cause as much as $9 billion losses in the insured industry. ETFs to Watch Since Canada was forced to see the shutdown of more than a third of the country's usual daily output, a significant tightening in oil supplies has been felt in the global market. As a result, oil prices jumped post Fort McMurray fire. Oil prices upped about 2% in trading early on Monday, as per Reuters. This might favor oil ETFs like United States Oil (USO) and United States Brent Oil (BNO). Notably, USO and BNO were up about 0.6% and 0.5%, respectively on May 6, 2016 (read: Top ETF Stories of April). Since Canada’s GDP will be hit, Canada ETFs may underperform due to this fire disaster. The fund iShares MSCI Canada (EWC) has 41.2% weight in the financial sector followed by 20.8% in energy and 11.5% in materials sector (see all Canadian Equity ETFs here). Another fund that could be hard hit is IQ Canada Small Cap ETF (CNDA). If domestic activities fall short extensively in May, then the fund may decline as small-caps are truly reflective of domestic actions. Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report >> Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report US-OIL FUND LP (USO): ETF Research Reports US BRENT OIL FD (BNO): ETF Research Reports ISHARS-CANADA (EWC): ETF Research Reports IQ-CANADA SC (CNDA): ETF Research Reports To read this article on Zacks.com click here. Zacks Investment Research Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report