Marijuana stocks tumble in first hours of Canada's legal market

Investor enthusiasm for cannabis stocks cooled Wednesday as Canada’s legalisation of adult use went into effect, dipping into a two month rally in the sector.

Aurora Cannabis was among the worst decliners on Wednesday shortly after the market opened, posting at 09:50 a 15% slide that gave investors their worst day since February.

However, the declines only brought most of the stocks to their lowest levels in a week. Tilray, which has surged more than 500% in the past two months, was the best performer, yet still posted a 4.2% drop.

• READ: It's high times for soaring marijuana stocks on Wall Street

The sector has been on a tear since mid-August on optimism ahead of Canada’s move to become the biggest legal market for recreational use of marijuana.

The ETFMG Alternative Harvest exchange-traded fund has added 62 percent since hitting its 52-week low on August 14, while the Horizons Marijuana Life Sciences Index ETF surged 70% in Toronto.