Atlantic salmon is one of Maine's true hard-luck species.

Rivers that once filled with tens of thousands of the majestic fish each summer have seen the numbers steadily decline to, in some cases, 10 or 20 fish. Even the intensive efforts to raise and release young salmon has seemed increasingly futile, with one in several hundred hatchery-raised fish somehow making the two-year-long journey to Greenland and back to spawn in its native river.

"The history of salmon is not a great story here in Maine," said Andrew Goode, director of U.S. programs for the Atlantic Salmon Federation.

But advocates like Goode now have some reasons to keep trying.

Salmon runs have doubled in size this summer, with the numbers of returning fish the highest in at least 20 years, experts say.