After three seasons, CBS summer drama series Zoo is coming to an end.

Zoo‘s run matches that of CBS’ first summer drama series under the current business model, Under the Dome, with both going for three seasons. Never a critical darling, the campy Zoo got off a strong start, especially in total viewers, earning a second-season renewal. But its ratings have eroded year after year — most recently to 2.65 million viewers and a 0.51 in adults 18-49 (Live+same day) for this past third season, making a fourth season unlikely. CBS already renewed its newest summer drama series Salvation, for a second season.

Based on the bestseller by James Patterson, Zoo chronicled a wave of violent animal attacks against humans across the planet. Zoo is produced by CBS Television Studios, distributed domestically by CBS Television Distribution and worldwide by CBS Studios International. Jeff Pinkner, Josh Appelbaum, Andre Nemec, Scott Rosenberg, Michael Katleman, James Mangold, Cathy Konrad, James Patterson, Bill Robinson, Leopoldo Gout and Steve Bowen are executive producers.