Montreal-based Cogeco Cable has announced it is acquiring Atlantic Broadband, a cable operator serving small communities in Pennsylvania, Florida, Maryland, Delaware and South Carolina for $1.36 billion, raising investor fears the company is once again on a spending spree.

Cogeco’s tarnished record of cable acquisitions was highlighted last year when it was forced to write off almost $250 million in losses racked up by its Portuguese acquistion Cabovisao. The company finally sold the money-losing operation at a loss in February.

Cogeco stock plummeted more than 17 percent on today’s news, and investors are concerned Cogeco’s entry into the U.S. market is competitively risky.

Atlantic Broadband’s cable systems were acquired from Charter Communications in 2003. Charter was consolidating its operations into larger markets, and the systems along the eastern seaboard were deemed too small to create the kind of large, regional clusters cable operators prefer today. Atlantic only serves around 252,000 customers nationwide, almost all in smaller communities and cities. That mirrors the way Cogeco operates in Ontario and Quebec — primarily in smaller cities bypassed by larger operators Rogers Cable and Vidéotron.

Cogeco CEO Louis Audet believes growth opportunities in Canada are limited at best. He defended the acquisition as an entry point in the United States, signaling Cogeco was going to continue shopping for other small U.S. cable operators.

Cogeco is paying about $5,400 per subscriber, according to Bloomberg News. That compares with $4,418 Time Warner Cable paid per subscriber for Insight Communications, and $5,486 for each Knology customer acquired by WideOpenWest LLC.

Cogeco acquired Atlantic Broadband from private-equity firms Abry Partners and Oak Hill Capital Partners.