UPDATE 1-First Quantum profit retreats on hedging loss

* Q3 adjusted EPS $1.95 vs analyst estimate $1.86

* Copper price falls, while output rises

* May seek arbitration in DRC contract dispute (In U.S. dollars unless noted)

TORONTO, Nov 10 (Reuters) - First Quantum Minerals (FM.TO) said on Tuesday its quarterly profit fell 16 percent, hurt by weaker copper prices and a $40.4 million hedging loss.

The Canadian copper and gold miner, which focuses on Africa, earned $123.8 million, or $1.59 a share, in the third quarter ended Sept 30. That compared with a profit of $147.5 million, or $2.16 a share, in the year-before quarter.

Stripping out the hedging loss, First Quantum earned $1.95 a share. Analysts polled by Thomson Reuters I/B/E/S had expected, on average, an adjusted profit of $1.86 per share.

Revenue slipped to $557.9 million from $563.9 million as realized copper prices eased to $2.26 a pound from $2.70 a pound, while production of the metal rose 14 percent to 93,486 tonnes.

First Quantum operates four mines in Democratic Republic of Congo, Zambia, and Mauritania.

It has also been developing the Kolwezi tailings project in the Congo, but the government canceled the project's contract in August following broad review of the country's mining contracts.

First Quantum said it continues to seek a negotiated solution to the dispute, but said it may have no choice but to file arbitration proceedings.

The company maintained its 2009 copper production outlook of 380,000 tonnes, and slightly lowered its expected gold output forecast to 205,000 ounces.

($1=$1.05 Canadian) (Reporting by Cameron French; editing by Peter Galloway)