The 26-year-old Bishop was acquired by Ottawa from the St. Louis Blues last season in exchange for a second-round pick.
Anderson suffered an ankle injury early in February, forcing both Bishop and Lehner to shoulder the load.
But with Anderson set to return, Bishop was the odd man out.
The six-foot-seven Bishop, who will be a restricted free agent this summer, has an 8-5-0 record in 2013 to go along with a 2.45 goals-against average and .922 save percentage.
Conacher, 23, has nine goals and 15 assists in 35 games this season with the Tampa Bay. He becomes the Senators' leading scorer, ahead of forward Kyle Turris and defenceman Sergei Gonchar (22 points each).