Lawrence Stevenson, a Certified Dog Behavior Consultant (CDBC) in Philadelphia, says the behavior seen in the video could be symptomatic of separation anxiety, but the clip doesn't contain enough clues to know for certain.
"There are all kinds of body language I can't see in the video. You can see him pacing around the house looking for his owner; he clearly misses his owner. The tongue flicks you see are also an indicator of anxiety, but the video is too brief to really make a diagnosis. After this short video the dog could have settled down, continued this level of distress or escalated into full blown Separation Anxiety. We don't know." says Stevenson.
"The cardinal rule about leaving dogs home alone is that a tired dog is a good dog. I would tell this person to make sure his dog gets enough exercise, and to give him environmental enrichment when he leaves, like a chew toy or something else the dog really likes. After, I'd have them contact a certified dog behavior consultant."
For more tips on how to alleviate anxiety in dog to make the time spent apart a little easier on everyone, check out the ASPCA's website here. To find a CDBC in your area, visit the International Association of Animal Behavior Consultants' website here.