(Adds quotes, five-year outlook)
VANCOUVER, Jan 17 (Reuters) - The world's biggest gold miners should partner to share the financial and other risks of developing large gold deposits, the chief executive of Goldcorp Inc G.TO , the world's third biggest gold miner by market value, said on Tuesday.
The gold mining industry "risks irrelevance" if it is not able to find and develop big new deposits to reverse the current trend of declining production and in-the-ground reserves, David Garofalo said, speaking at Goldcorp's investor day.
"What we are looking to do on the M&A side is find more of those large resources that are undeveloped right now and do so in partnership with some of our senior peer companies," he said.
"It is better to have two heads, to have two technical teams, two balance sheets," he said.
Corporate mergers and acquisitions, where one gold miner buys another, were likely not on the cards for any of the big producers as they are "very difficult to do", Garofalo said.
Vancouver-based Goldcorp late on Monday said it expects to increase gold output by 20 percent to about 3 million ounces over the next five years, while its all-in sustaining costs - the industry benchmark - are expected to fall by 20 percent to $700 an ounce.
Its gold reserves are forecast to rise 20 percent to 50 million ounces in the same period from the conversion of existing resources at its Century project in Ontario, Peñasquito mine in Mexico and Pueblo Viejo mine in the Dominican Republic.
Goldcorp's stock was 1.62 percent higher at C$19.46 on the Toronto Stock Exchange, slightly ahead of its peers.