Fox’s Fringe returned to the air after a month-long break. But based on the preliminary numbers, not every fan came back to watch.

Fringe delivered 2.9 million viewers and a 0.9 rating in the adult demo, even with NBC’s Grimm airing a repeat. That’s down 25 percent from the drama’s last original airing at the end of February and appears to be a season low. CBS showing the NCAA Basketball semifinals might have had an impact, plus some fans were probably unaware the show was returning last night. Still, it doesn’t help Fringe‘s renewal chances (we hear the studio has been pitching a reduced Fringe license fee in exchange for a final season order … but when shows drop below a certain rating, they can become too expensive — even if they’re free).

ABC’s Shark Tank (5.9 million, 1.5) was down slightly. CW’s Nikita (0.5) was up a tenth; Supernatural (0.6) was down a tenth.