Companion animals experience grief responses following the loss of bonded companions — human or animal — with behavioral changes that indicate genuine emotional suffering requiring empathetic owner response.
Animal grief is increasingly recognized as a genuine welfare concern rather than simple behavioral disruption. The behavioral changes following companion loss — reduced appetite, searching behavior, vocalization, and social withdrawal — represent subjective emotional states that cause suffering. Strong evidence exists for grief-like responses in elephants, great apes, dolphins, and dogs, with credible evidence in cats and other social species. Owners who dismiss animal grief responses as meaningless or misinterpret them as behavioral problems rather than emotional states may inadvertently worsen welfare by failing to provide appropriate support. Human companions play an important role in supporting bereaved pets through increased social interaction, maintenance of routine, and patience during the adjustment period. In prolonged or severe cases, veterinary assessment for anxiety treatment may improve welfare.