Not everyone agrees that the solution to North America’s salmon problem lies in producing more fish from hatcheries, even with the best of science.

Critics of hatchery programs often seize upon the high costs and low returns in their campaigns to lessen dependence on artificial propagation and focus more on habitat restoration and dam removal.

Conservative estimates indicate local, state and federal organizations spent more than $5 million combined in the past year to net salmon returns of about 1,100 in the Penobscot and nine other Maine rivers. Critics also often question whether hatchery-raised fish, which they say are less likely to survive than wild salmon, are weakening the gene pool.

A 2001 report by the international conservation group World Wildlife Fund said released salmon compete for food with wild fish. And although hatchery fish have poorer survival rates than wild stocks, released salmon are generally larger than wild fish and therefore may have a competitive advantage. This can result in “substantial impacts” to wild stocks, especially when hatchery fish are released in large numbers, the WWF report stated.

More often, however, salmon hatcheries are regarded as a necessary evil.

Andrew Goode, vice president of U.S. operations for the Atlantic Salmon Federation, which is one of the world’s largest salmon conservation groups, said there is no question in his mind that hatchery fish are having a negative effect on the wild populations.

Goode said that after more than 100 years of experience with hatcheries in the U.S., fish populations are still in decline or far from recovered. Unfortunately, there are few other options right now, he added.

“So for us, we hope this is an interim measure,” he said. “They are necessary to keep the population on life support for the moment until we can get the numbers back up. … But we don’t have any alternative, basically. So the goal should always be in the state of Maine to put the hatcheries out of business.”

Biologists who make their living working in hatcheries agree, to a point.

“There is no question we would rather not be growing these fish in a hatchery,” said Fred Trasko, assistant manager at the Green Lake hatchery, while helping his crew load thousands of salmon smolts into a truck for stocking. “We would rather be moving on to another species.”

Experts with government agencies and conservation groups, meanwhile, are increasingly emphasizing that salmon restoration efforts cannot happen in isolation. To successfully save the salmon, the state must also save the many other species that are part of ecological web, they said.

“We believe having all of the species back is important to salmon recovery,” said Joan Trial, a biologist with the Maine Atlantic Salmon Commission.