Dogs Grieve When Other Dogs Die, Study Suggests

Dogs are our closest friends, our biggest cheerleaders, and cherished members of our families, so it’s only natural that we experience profound heartbreak over their deaths. However, humans may not be the only members of a household who mourn their canine companions, according to a new study that surveyed hundreds of owners of multiple dogs. 

Participants of the survey reported that their surviving dogs also exhibit grief-like behaviors over the death of their fellow canines, a result that reveals another layer of the rich emotional lives of our furry friends. This conclusion won’t come as a surprise to anyone who has witnessed their dog expressing sadness over the death of their canine companion for weeks or even months, but now there is a scientific effort to back those anecdotal experiences up.

This discovery of these grieving behaviors exposes what is “potentially a major welfare issue that has been overlooked, considering the relatively high number of dogs who live with at least another companion dog and the dog aging population,” notes the study, which was published on Thursday in Scientific Reports.

“Today millions of families around the world live with more than one dog,” said Federica Pirrone, a lecturer of veterinary ethology and animal welfare at the University of Milan and senior author of the study, in an email. “Knowing the behavioral reactions and emotions aroused by the death of a companion dog is therefore fundamental because it will allow us to recognize the emotional needs of many animals, which are actually at risk of suffering from the loss of a canine companion.” 

Many different animals have been observed displaying grief responses, and even rituals, over the deaths of their conspecifics, including great apes, whales, dolphins, elephants, and birds. To establish whether domestic dogs also experience these emotions, Pirrone and her colleagues enlisted 426 Italian adults with multiple dogs to complete an online survey called the Mourning Dog Questionnaire about both their responses, as well as their dogs’ behaviors, in the wake of the death of one of their canines. 

Eight-six percent of owners reported negative reactions to the death of a dog in the surviving dogs, which were broken down into the following categories: Seeking more attention (67 percent of participants), a decline in playfulness (57 percent), a decline in activity (46 percent), an increase in sleep (35 percent), an increase in fearfulness (35 percent), a decline in eating (32 percent), and an increase in whining and barking (30 percent). 

Roughly a third of owners said that these behaviors lasted between two and six months after the death of their canine companion, and a quarter reported that they lasted more than six months. The duration of these behaviors was not affected by whether or not the surviving dog saw the corpse of its companion, and was also not influenced by the animals’ sex, neuter status, breed, or age at the death of their companion.

Ninety-two percent of the owners said their dogs had lived together for more than a year, but interestingly, the amount of time that the two dogs shared a household did not have any bearing on the odds of grief-like behaviors in the surviving dogs. A friendly relationship between the dogs—which was measured by the pets enjoying activities together, such as eating, grooming, and playing, or sharing food, toys, and resting areas—was a much stronger predictor of negative reactions in the survivor compared to the time they lived together.  

Of course, there is a danger of bias in self-reported surveys as owners might inflate the negative behaviors of their dogs, project their own feelings onto their companions, or provoke negative reactions in their dogs due to their own grieving processes and changes in mood. To counteract these types of inconsistencies, Pirrone and her colleagues cross-referenced the reports and performed a statistical analysis to assess whether participants were genuinely witnessing grief-like responses in their dogs. 

“This particular structure of the questionnaire, and the statistical analyses we run, allowed us to identify when participants’ responses concerning a dog’s changes were more likely to be influenced by their own perceptions and emotions,”  she explained. “As for many aspects, therefore, it was possible to make this influence emerge or, on the contrary, to exclude it, making it more likely that the reported changes were real.”

One particular issue that needed to be vetted, for instance, is the disparity in responses between men and women. Only 42 men participated in the study, compared with 384 women. Pirrone notes that this gender difference consistently crops up in web surveys about animals and human-animal relationships, indicating that women are much more likely to participate in these studies.

“This has been the case also in all our previous studies in which we investigated pet ownership using online surveys,” Pirrone explained. “Research exploring the role that gender plays in people’s attitude towards animals has found that women tend to be more empathic and to have a higher concern for animal welfare compared with men. Thus, our finding could be at least partially explained by females being more willing to fill out online surveys on pets than males for their particular sensitivity to animals’ issues.”

The study’s overall results suggest that dogs do grieve their fellow canines, though much more research into the topic needs to be conducted to confirm that assumption. To that end, Pirrone and her colleagues hope to build on this study by assessing the possible drivers of mourning behaviors in dogs.  

“We are already working on the next step of the project, which aims to confirm that the dogs are responding to the ‘loss’ of an affiliate, and hopefully to even discover whether dogs are only responding to such loss, or even to their ‘death’ per se,” Pirrone said.

“The understanding of behavioral patterns after loss in non-human animals can be helpful in recognizing these animals’ emotional needs,” she concluded. “The results of this research tell us that domestic dogs may react negatively when a companion conspecific dies. Recognizing and being able to predict these reactions and underlying emotions allows us to identify the most effective strategies to support them and their owner in coping with these difficult circumstances.”