TORONTO (Reuters) - Toronto's main stock index ended slightly higher yesterday, rebounding from steep losses early in the session as oil prices climbed back from lows and optimism grew about the global recovery.

The main thrust of the bounce-back came from the index's heavily weighted energy sector, which ended up 0.6 percent..

Shares of Suncor Energy Inc. rose 2.1 percent to C$35.33, and Canadian Natural Resources gained 1.3 percent to 61.67. US crude ended down 49 cents at $85.39, but that was more than $1 off the day's low point.

Shares of Athabasca Oil Sands Corp., Canada's biggest initial public offering in more than a decade, fell 6.1 percent to C$16.90 in their debut on the Toronto Stock Exchange, below their pre-market price of C$18.

Gold prices pushed above $1.150 an ounce, helping prop up the index's mining-heavy materials sector, which finished up 1.2 percent.

Goldcorp ended up 0.7 percent at C$40.35, while Barrick Gold gained 0.5 percent to 41.10.

The Toronto Stock Exchange's S&P/TSX composite index rose 2.63 points, or 0.02 percent, to 12,113.53. Three of the index's 10 main sectors were up, with industrials rising along with the energy and materials groups. Financials ended flat.

Early in the session, the index was down more than one percent. Investors may see a lot more turbulence on the market in the coming months, said Michael Sprung, president at Sprung & Co Investment Counsel. "After the gain we've had over the last year, my opinion is that the market is perhaps running a little ahead of fundamentals here, so people are going to be taking a wait and see attitude," he said.

"In the meantime, the fears of sovereign debt, whether it's Greece, Italy, Portugal, Ireland, Spain, or even the UK, that's going to continue to overhang the market, so I'm not sure that we are going to see any clear direction for a while."

In the United States, unexpectedly robust March retail sales numbers helped cheer investors, possibly pointing to strong US corporate earnings. Sprung said the optimism may have spilled north and helped to lift the TSX from its lows, as the US is by far Canada's biggest export market.

On the downside, shares of Shoppers Drug Mart , Canada's biggest drugstore chain, plunged as investors assessed the fallout from Ontario's plan to reduce generic drug prices. Its shares ended down 9.8 percent at C$38.92.

Also undermining the market yesterday were persisting worries over Greece's public finances and sovereign debt defaults in Europe, as well as data that showed a rise in US workers filing new claims for unemployment insurance last week.

The next big Canadian economic release is jobs data for March today. Market players are expecting a net gain of 25,000 jobs, up from the 20,900 jobs added in February.