* Q4 gold output down 18 pct from year-ago
* Q4 loss/shr $0.25 vs $0.23 last year
* Sees 2011 Fosterville gold prodn at 97,000-102,000 oz
* Cash flow from operations up 36 pct (Adds forecast, details)
March 8 (Reuters) - Canadian gold miner Northgate Minerals Corp posted a wider quarterly loss, hurt by lower production and higher costs, and forecast that output at one of its biggest gold mines would be flat, at best, this year.
P roduction at the Fosterville mine in Victoria, Australia, -- which produced 35 percent of Northgate's gold in the quarter -- is forecast at 97,000-102,000 ounces versus 100,441 ounces in 2010.
Northgate posted an October-December net loss of $72.0 million, or 25 cents a share, compared with a net loss of $67.8 million, or 23 cents a share, a year earlier.
Fourth-quarter gold production declined 18 percent to 66,077 ounces from a year earlier, while copper output was down 10 percent to 10.6 million pounds.
The average net cash cost of gold was $646 per ounce, up from $537 a year earlier.
The company, which has development and exploration projects in Canada and Australia, posted adjusted profit of 6 cents a share, in line with analysts' expectations, according to Thomson Reuters I/B/E/S.
Revenue rose 34 percent to $148.7 million, but missed analysts' estimates for $151.8 million, and cash flow from operations increased 36 percent to $56.5 million, or 19 cents a share.
Northgate said realized gold prices on average rose 18 percent in the fourth quarter to $1,393 an ounce, while copper prices rose 21 percent to $4.27 a pound.
Shares of the Vancouver-based company, which have lost about 12 percent in the last year, were trading up nearly 1 percent on Tuesday on the Toronto Stock Exchange. (Reporting by Aftab Ahmed and Bhaswati Mukhopadhyay in Bangalore, Editing by Ian Geoghegan)