That's right: From June 3 to July 2, there'll be a post each day highlighting Teenage Mutant Ninja Turtles canon immigrants. Now, because TMNT canon is a little confusing, it can be hard to tell what counts as a canon immigrant and what doesn't. So for the purposes of this blog, a TMNT canon immigrant is anything (a) from the movies, cartoons, video games, toy lines, or tie-in comic series that later appeared in (b) TMNT volumes 1, 2, or 4 [because they're by the original creators] or TMNT volume 5 [because the original creators are involved, it's the new official continuity, and its goal is to use as much of the diverse TMNT lore as possible].
Agent Bishop is a recurring villain in the 2003 series. First appearing in the episode "Space Invaders, Part 2" (October 2004), he's a Man in Black whose goal is to eliminate alien threats. He also has a personal vendetta against aliens because he was abducted when he was a kid.
I hear he makes an appearance in Mirage's Tales of the TMNT, but I can't find any proof of that. If anyone has an issue number or a scan, please let me know.
Luckily, he also appears in IDW's Teenage Mutant Ninja Turtles #54 (January 2016), and will probably make more appearances in the future.