"But it will lower the presence of the bank by not having their name there and getting free publicity when teams play at 1st Mariner Arena," he said.
First Mariner executives disclosed that the bank would not bid for the naming rights during a question-and-answer session after the parent company's annual meeting Tuesday.
The closings come in response to the growth in customers using electronic services, such as online banking, Finnegan said. When the branches are closed, the bank will have 18 branches, down from a peak of nearly 30 about a decade ago.
Eighteen employees will be affected by the closings, and all but three or four will be transferred to other jobs at the bank.
Overall, First Mariner has added staff in the past year. At the end of March, it had 603 employees, up from 539 the year before. Though some areas of the bank have lost staff, the bank has added 75 positions in its mortgage operations, which originated more than $720 million in residential loans between January and March, an increase of 56 percent from a year earlier.
Also on Tuesday, the company announced a loss for the first quarter of 2013, its first loss after four profitable quarters in a row, as it disposed of bad loans and foreclosed real estate.
The bank holding company lost nearly $2.3 million, or 12 cents a share, in the quarter that ended March 31, compared with a profit of $1.8 million, or 10 cents a share, a year earlier.
The company said it took a charge of $4 million in the January-to-March quarter as part of a move to dispose of more than $14 million in nonperforming assets. The bank's ratio of nonperforming assets to total assets fell to 3.2 percent March 31, down from 4.1 percent at the end of last year.
First Mariner had $1.38 billion in assets at the end of March.
The company's stock closed Tuesday at $1.55 a share, down 28 cents.