I don't know exactly how often who puts headphones on seals yet, but it sounds like as part of operating at Vandenberg, it's routine to "haul out" (by which I assume they mean, capture and remove, releasing some time/distance away) harbor seals, so they aren't in the way; it sounds like they also (sometimes? always?) perform some amount of monitoring activities on the seals, since you've already got them captured.
Also, all of this activity is apparently termed "Level B harassment".
Boeing, probably related to the pictures on the internet: https://www.federalregister.gov/documents/2006/06/26/E6-1004...
SpaceX, related to the landings: https://www.federalregister.gov/documents/2018/11/15/2018-24...
I don't know exactly how often who puts headphones on seals yet, but it sounds like as part of operating at Vandenberg, it's routine to "haul out" (by which I assume they mean, capture and remove, releasing some time/distance away) harbor seals, so they aren't in the way; it sounds like they also (sometimes? always?) perform some amount of monitoring activities on the seals, since you've already got them captured.
Also, all of this activity is apparently termed "Level B harassment".