Your dog may be barking due to separation anxiety if:

• The barking occurs only when you're gone and starts as soon as, or shortly after, you leave.
• Your dog displays other behaviors that reflect a strong attachment to you, such as following you from room to room, greeting you frantically, or reacting anxiously whenever you prepare to leave.
• Your dog has recently experienced a change in the family's schedule that means he's left alone more often; a move to a new house; the death or loss of a family member or another family pet; or a period at an animal shelter or boarding kennel.