Shares in three of Canada's largest oil companies are trading lower on Thursday despite improved profits.

Suncor Energy, Imperial Oil and Talisman Energy each lost ground.

Imperial's net profit in the second quarter rose 40 per cent to $726 million or 85 cents a share on a sharp jump in revenues caused by higher oil prices and improved production at its Cold Lake oilsands business.

Revenues jumped to $7.7 billion from $6.1 billion as the company benefited from higher world oil prices.

But its shares closed down 43 cents, or one per cent, to $42.50 on the Toronto Stock Exchange.

Higher oil and gas prices helped Suncor improve its second-quarter earnings to $562 million from a year-earlier $540 million even as production took an expected dip and it booked a $514-million writedown on its Assets in war-torn Libya.

Suncor production down

Suncor's production averaged 460,000 barrels of oil equivalent per day — a significant drop from 633,900 barrels during the second quarter of 2010 but in line with Suncor's expectations after it sold some non-core assets, shut down oilsands operations for planned maintenance and shut in production in Libya.

"With major maintenance at our oilsands operations successfully behind us, we're looking toward a strong second half to the year and steady production through 2012," president and CEO Rick George said in a statement.

Suncor shares closed down $1.05 cents, or 2.75 per cent, to $37.09 .

Talisman shares slipped a 76 cents, or 4.05 per cent, to $17.99 even as the company reported profit and revenue that beat expectations.

Net income rose to $698 million or 68 cents a share in the second quarter ended June 30, compared with net earnings of $572 million in the same quarter last year.

Total revenue and other income for the quarter was just over $2.2 billion compared to $1.6 billion in income in the second quarter of 2010.

Analysts expected Talisman to earn 30 cents per share with $2.1 billion of revenue.

With files from The Canadian Press