AUGUSTA – The Atlantic Salmon Commission board got an earful Thursday from longtime anglers frustrated with the decision to keep the Penobscot River closed to salmon fishing for at least one more spring.

Citing concerns about fish losses and faced with rigid regulatory time frames, commission board members reaffirmed their decision to scrap any plans for a spring 2007 season for sea-run salmon. The commission will revisit the issue for 2008.

The board did, however, give staff a green light to begin planning another 30-day catch-and-release season on the Penobscot this fall following the success of last fall’s fishery, the first in Maine since 1999.

But the prospect of another fall season did little to satisfy the hardcore anglers and salmon enthusiasts who attended Thursday’s meeting.

“I think you missed a great opportunity here,” said Vaughn Anthony, a retired fisheries biologist with the federal National Marine Fisheries Service. “People were primed for a very brief, experimental catch-and-release fishery.”

The debate over whether to allow fishing in the spring versus the fall is about much more than just timing. It involves fish numbers, water temperatures, fish mortality predictions, angler interest and a rich springtime salmon fishing tradition in Maine.

Anglers prefer to fish in the spring, when salmon numbers are higher and the fish are fat and strong from months or years in the ocean. Over the course of a century, the Penobscot earned a worldwide reputation as a premier springtime salmon fishing destination.

But dams, overfishing and habitat loss, among other factors, took their toll on salmon populations throughout New England. Maine closed the Penobscot to fishing for sea-run salmon in 1999.

The number of adult fish returning to the Penobscot annually to spawn has rebounded in recent years, thanks to multimillion-dollar hatchery and restoration programs. Today, the Penobscot boasts the only sizable run of Atlantic salmon in the U.S.

Following last fall’s experimental season, the board asked commission staff to use historic records to calculate the risks that a spring season would pose to the fish population.

Combining fishermen turn-out and success rates during those years with fish counts in recent years, commission biologists predicted that anywhere from five to 17 salmon would likely die as a result of inadvertent injury, fatigue or other fishing-related causes. At least half of those fish would likely turn out to be egg-carrying females.

Board Chairman Dick Ruhlin, a lifelong salmon fishermen, said he could have lived with “sacrificing” five or six salmon in order to revive public interest in salmon angling and restoration in general. But the upper estimates were too high, he said.

Board member Roland “Danny” Martin, who is commissioner of the Department of Inland Fisheries and Wildlife, agreed with the decision.

“Clearly, I hope I live long enough and [am] here long enough to see a spring fishery, but I don’t think we are there yet,” Martin said.

Ruhlin said he and the other board members weighed holding a limited-entry salmon season earlier in the spring when fewer fish would be present. But there was not enough time to prepare administratively for a limited season, he said.

Anglers disagreed with the decision and the staff’s calculations.

Gary Arsenault and Lou Horvath said a catch-and-release season in 2007 would attract far fewer fishermen than the unrestricted days in the early 1980s. They said angler turnout during the late 1990s would have been more accurate and would have provided lower mortality rates.

The critics also said the commission could easily have closed the fishery if mortality rates rose. Even a one- or two-week season would have engaged the public, they said.

“Right now with the fishery closed we are not getting publicity, we are not getting public support,” said Alfred Meister, who served as the commission’s chief biologist for two decades. “We don’t have people on the river and we are cutting our own throat.”

In the end, the commission agreed to begin the administrative process earlier for considering a spring 2008 season. The board will likely hold a scoping session on the proposal later this spring or summer.