He had not been seeking the post, but Ward 4 Councilor Jerry L. Ryan said he is pleased to be able to serve another year as council president. Ryan, who held the leadership post in 2011, was unanimously chosen by the council Jan. 7 to serve as its president in 2013. Ryan said he emerged as the compromise choice for the position when two of his colleagues who had been seeking it — Michael Sosnowski and Robert K. McCarthy — were both unable to secure the votes needed. “I wasn’t expecting it, but I’m willing to take on the challenge. It’s going to be hopefully easier the second time around,” said Ryan, who is in his third term on the council. The election of the president was overshadowed by the council’s selection of a new at-large member to fill the seat that Joan B. Lovely gave up as a result of her election to the state Senate. On the 302d ballot in the second night of voting, councilors on Jan. 8 elected William Legault to the seat. Ryan, who works as an agent for Eastern Insurance, said that moving forward with the longstanding effort to clean up the city’s contaminated transfer station site on Swampscott Road is one of his priorities. Others include advancing the development of a new senior center and implementing the Community Preservation Act, which voters adopted in November.