The short list of internal candidates from Bangor Police Department who submitted applications to succeed Police Chief Don Winslow, who will retire at the end of February, has dropped to one, City Manager Edward Barrett said Thursday. He said Deputy Chief Peter Arno has withdrawn his name. Lt. Ron Gastia confirmed Thursday that he is the remaining candidate. After Winslow retires, he plans to take a month’s vacation with his wife, he said Wednesday during a Bangor Noon Kiwanis meeting. His last day on the job is Feb. 28. Winslow started as a patrolman in 1979 and became chief in 1998. Whomever is recommended by the hiring panel – either the remaining internal candidate or someone from a broader search – will be presented to the City Council for final approval. The hiring panel is composed of Barrett, Assistant City Manager Robert Farrar and an unidentified Maine police chief.