Channel 9 yesterday dropped weekend sportscaster Lee Zeidman, who had been with the station about 2 1/2 years . . .

Dave Pearce, news director at WDVM, said Ken Mease, most recently with KDKA in Pittsburgh, would replace Zeidman starting this weekend . . .

Pearce said Zeidman had been working without a contract for several months. "He's done an adequate job," said Pearce, "but frankly I've been looking around" . . .

He said, "I think viewers will like Mease once they get used to him. He's kind of chubby and he has something of a high voice." (Airwaves thinks he's going to like Mease, anyway) . . .

Mease has been in broadcasting for some years, including stops at WBTV in Charlotte, N.C., and WPRI in Providence, R.I. . . . He had been with KDKA since 1974 . . . Meanwhile

ABC started its segment of the annual winter network press tour here yesterday with a typically engaging "state of the network" review by its new Entertainment president, Brandon Stoddard . . .

But the big news around ABC seemed to be in New York, where rumors were flying that Fred Pierce and perhaps key members of his staff were about to depart . . .

Pierce was president and chief operating officer of ABC Inc. until last Friday, when he became vice chairman of Capital Cities/ABC Inc. and chairman and chief executive officer of ABC under terms of the $3.5 billion merger that was completed last week by Capital Cities Communications Inc.

One rumor here had "everybody at ABC going except ABC Sports/News President Roone Arledge and Stoddard" . . .

But sources in New York, who said the speculation has been persistent all this week, indicated that no such radical changes were expected . . .

"If I had to guess, it might be Fred and one of his top assistants. Some kind of an announcement could be forthcoming in the next day or so," one ABC executive -- who admitted he knew little more than the rumormongers -- speculated yesterday. "What's holding it up is probably the terms of Fred's settlement" . . .

Pierce was a key figure in ABC's move to the top in the mid-'70s and enjoyed ABC Chairman Leonard Goldenson's confidence. But in recent years, Goldenson's confidence that Pierce had the management ability to replace him as chairman of the company he had founded reportedly cooled a little.

Goldenson's verdict was believed to be a key factor in his move last year to consider the Cap Cities takeover offer and the realignment of top management that almost certainly would follow . . . Stoddard Talk

ABC Entertainment President Brandon Stoddard hinted strongly yesterday that the network will cancel "Amerika," the multimillion-dollar mini-series about American life under 10 years of a Soviet occupation of the United States . . .

He said that because of recent public Soviet criticism of the project (which also included "Rambo" and "Rocky IV") for being, in Stoddard's words -- "antithetical to the spirit of the Geneva summit" -- it would be "only responsible that the situation be factored into the decision" whether to go ahead with "Amerika" . . .

But he said that the decision would not be based on what the Russians said.

He suggested that budgetary problems were the primary consideration in the network decision to rethink the project . . .

At one time "Amerika" was to be at least 16 hours. Yesterday, Stoddard said that the length had been whittled down to 12 hours, with a February 1987 air date as a goal . . .

He said they are now rebudgeting the show and he hopes to see the revised figures "in a week or so." A decision whether to go ahead or not will be made soon thereafter.

There have been reports that ABC originally was to spend up to $40 million on the project, which would have been filmed on location in the Midwest. Minnesota was originally considered, but Kansas -- site of ABC's controversial doomsday movie, "The Day After" -- reportedly is the current choice . . .

Stoddard had been the father of the miniseries in his previous job as head of movies and mini-series for ABC.

Yesterday -- apparently speaking to a broader public than the 100 or so TV writers from around the country here on the tour -- he said the mini-series "was not about the Russians or what they do in an occupation. It's about what Americans do, about freedom and responsibility, the American character" . . .

Stoddard also confirmed that the network is looking "very carefully" at the recent slippage in "Dynasty."

"A number of mistakes have been made," he said. "The Moldavia story has not been sensational." He predicted that by late January or early February the series will be "back on the track. Alexis will come back to confront Blake and it should be very exciting through the rest of the year."

Producers reportedly will phase out the King and the Prince of Moldavia, and Krystle's look-alike, and add a couple of new characters, including a long-lost brother for Blake . . .

(Airwaves OD'd on Krystle's shoulder pads and Alexis -- to say nothing of Blake's knack for always picking a fight -- about a year ago, but then nobody asks Airwaves for his opinion. Though they often live to regret it) . . .

Stoddard also said the network "is in the process of evaluating 'Good Morning America,' " the early morning show that is under siege from NBC's "Today," after years of leading its time slot . . . "We'll look very carefully at the show" . . .

Stoddard, who took questions for about an hour, sidestepped any direct answers as to how long he thought it would take to get ABC back in primetime contention. Nor did he pick out any show or any producer in the current ABC schedule for either criticism or praise . . .

He did admit, however, that "over the past few years I've grown tired and frustrated with programs that have little to do with emotion, lots to do with meaningless action sequences, and promotion that screams and oversells to an audience" (Do you get the idea Brandon's been watching ABC the last couple of years?) . . .

"I believe that the audience is not being treated with an essential attitude, respect. I think that the audience is demanding more. More excitement, more freshness, more intelligence and more respect."

He admitted that his were "lofty, passionate and idealistic goals" that could not always be met . . .

As for a timetable, Stoddard recalled that he recently told the head of an important ABC affiliate that it would take "a long, long, long time" . . .

"That's one long too many," the affiliate executive warned him . . .