Shares of the Salt Lake City-based oil and natural gas exploration and production company declined $4.77 to close at $52.73, the lowest closing price for the energy company's stock since Feb. 8.

"Questar isn't alone. A lot of the big natural gas names were down," said Holly Stewart, an analyst at Howard Weil Inc. in New Orleans.

Adding to that pressure, production at Questar's Uinta Basin property in Wyoming "was down year over year where they had some gathering issues," Steward said. "And two of their new plays - the Haynesville Shale and the Bakken Shale - won't add significantly to production for a few years."

Still, the company reported its second quarter net income rose 54 percent because of higher prices and companywide production gains.

"All of our business units posted record net income in the first half," Keith Rattie, Questar's chief executive, said Tuesday during a conference call with investors and representatives from the securities industry.

Second quarter income reached $172.6 million, or 98 cents per share, up from $112.2 million, or 64 cents a share, in the same quarter a year ago. Those results led the company to raise earnings projections for the entire 2008 fiscal year.

"We now expect 2008 net income to range from $3.50 to $3.60 per share," said Stephen E. Parks, Questar's senior vice president. He noted that earlier this year Questar was projecting its 2008 earnings per share would fall somewhere between $3.25 to $3.40.

Questar said it expects oil and gas production growth of 14 percent to 16 percent this year.

Net income at Questar Gas Co., the regulated utility that provides most Utahns with the fuel to run their water heaters and warm their homes in the winter, was $28.6 million in the first half of 2008, or 2 percent higher than the year earlier period.

Questar attributed that increase primarily to the growth in the number of customers its natural gas utility serves. It noted that as of June 30, Questar Gas was serving 881,500 customers, up 19,400 customers or 2.3 percent from June 30, 2007.

For the first half of 2008, Questar reported net income of $358.4 million, or $2.03 per share, compared to $263.3 million or $1.50 per share for the same period in 2007, a 36 percent increase.

steve@sltrib.com