Scientists in northern New England, including Maine, as well as Nova Scotia and other parts of Canada report some dramatic increases in salmon returns this year. In some rivers in Maine there haven't been this many salmon counted in more than 20 years.

The trend will have to continue over several years before biologists say they can get truly excited and before they can figure out what might explain the numbers.

So far this season more than 3,100 Atlantic Salmon have been trapped and counted in the Penobscot River. Oliver Cox, a biologist with the Maine Department of Marine Resources says that's double the number of fish that returned last year. In the Narraguagus River in Washington County there have been 186 salmon counted. That's also double the number from 2010. The Merrimack River in New Hampshire is seeing its biggest salmon run in more than 20 years. It's a similar story throughout the region, which Cox says provides a clue about what's going on.

"If we saw just an increase on one or two rivers and the other rivers that we look at stayed the same or decreased than we would look to those rivers," said Cox. "What was different management wise? But when you have a lot of rivers showing high returns than you tend to think something positive happened that's affecting all of the salmon."

Salmon spend the early part of their lives in their native rivers before they migrate toward Greenland where they feed and grow for at least one winter before returning home to spawn. It's not yet clear what is happening in the ocean that has benefitted the fish. There's been a moratorium on commercial fishing near Greenland for almost ten years. Andy Goode of the Atlantic Salmon Federation says that may be helping along with other factors.

"It may take a couple of years to really tease out why we're having the big runs but certainly conditions in the marine environment have improved," Goode said. "Certainly the fish that are coming back are bigger, seems to be more forage out in the marine environment off the coast of Greenland where salmon are going."

Atlantic salmon were added to the Endangered Species list in eight OF the state's rivers more than a decade ago. Salmon in several other rivers were later added to the list. With listing comes a set of regulations, including restrictions on killing or harassing the fish. That's because the salmon's numbers are a fraction of their historic high numbers in places like the Androscoggin which has had 47 returns so far.

"This is a pretty exciting year for the Androscoggin. As pitiful as 47 are, that's a big number. We've had as few as three come back to this river," said Neil Ward. He is the executive director of the Androscoggin River Alliance, which this year paid to have 20 salmon fitted with radio telemetry equipment so their movements and habits can be followed during the next year.

"We don't know as much as we think we know about salmon migration," Ward said. "We certainly don't know what's happening to them once they reach the Atlantic. Certainly these numbers give us hope that things are getting better."

But while many Maine rivers are seeing an increase in salmon returns, Ward pointed out there are still big challenges for the fish. Case in point: one of the tagged fish has already been illegally poached. Charges in the case are pending since the fish was able to be tracked by the Department of Marine Resources. But Ward said the incident suggested that more needs to be done to spread the word that Maine salmon are endangered and it's a crime to take them.

Maine DMR, Bureau of Sea-Run Fisheries and Habitat, Fish Trap Counts

Trap Counts

• Androscoggin - Brunswick

• Aroostook - Tinker Dam

• Dennys - Weir

• Kennebec

• Narraguagus - Cherryfield

• Penobscot - Veazie

  • Historic Trap Count Numbers

• Penobscot - Weldon

• Saco - Cataract

  • Historic Trap Count Numbers

• Saco - Skelton

• St. Croix - Milltown

• Sebastiocook River - Benton Falls

• Union - Ellsworth