Rookie forward Cory Conacher is heading back to the Senators, along with a fourth-round pick. Conacher is second among rookies with 24 points this season, but he has two goals and two assists in the past 12 games.
Conacher, though, has more goals (nine) and points than any player on the Senators.
"We wish [Conacher] was 6-foot-7, but he's not. He's a guy that addresses a need for points," Ottawa general manager Bryan Murray said of the 5-foot-8 forward.
The Senators also have Craig Anderson and Robin Lehner in net, making Bishop expendable. Anderson is due back from his ankle injury soon.
"We've had a chance to watch him for a couple of years, and he's a big guy and he handles the puck well, so moving forward we believe that he will really solidify our goaltending," Lightning general manager Steve Yzerman told the team's website.
Yzerman signed Anders Lindback to a two-year, $3.6 million contract last summer hoping he would solve the team's goaltending problems. Lindback, though, is 10-7-1 with a 2.88 goals-against average and .903 save percentage and is on injured reserve with a sprained ankle.
Bishop, who is a restricted free agent after the season, likely will compete with Lindback for the No. 1 job next season provided he re-signs with the Lightning.
"I'm excited and I think it will be a lot of fun," Bishop told the Lightning's website. "Steve Yzerman adds a lot of credibility, (coach) Jon Cooper has won everywhere he’s gone, and I know some of the guys on the team, so I can't wait to get down there are start playing."
Mathieu Garon and Cedrick Desjardins, who are handling the goaltending duties in Tampa Bay with Lindback out, will be unrestricted free agents after the season.
Bishop was 8-5-1 with a 2.45 GAA and .922 save percentage for the Senators this season. He was drafted by the St. Louis Blues in 2005, but was traded to Ottawa for a second-round pick in February 2011.
"The idea is to get [Bishop] signed," Yzerman said. "That is our intention and we expect that to get done and to move forward into next season with Anders and Ben. They're both relatively young guys with great potential."