The attached figure shows a cWB outlier that Brennan H. sent around to DetChar. It is compared to likely raven pecks discussed in this log: https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=37630  The match is quite good (see figure), though, in this case, the peck did not produce a very loud sound. But the above log suggests that the coupling path for pecks is not through the air, but through the GN2 vent to the vacuum enclosure. While the sound for the cWB outlier was not that loud, the vibration of the enclosure was strong and sensed by the BSC10 accelerometers. The vacuum enclosure motion likely couples to DARM through the P-Cal periscope (see above log). It looks like there is a broader resonance in the vent/vacuum enclosure system, excited by ice-craving ravens, that overlaps with the 94 Hz resonance of the P-Cal periscope, that is strongly coupled to DARM through scattered light.