Sometimes in the evenings around my house in Tennessee, we can hear the plaintive cries of neighborhood dogs and coyotes. Many times they seem to be responding to sirens or the howls of other dogs. I have heard people say that the sirens may hurt their sensitive ears. My dogs join in and I wanted to know what science says about why dogs howl.
Many animal species use long-range calls to establish their use of space and their relationships with members of their own and other species according to an article in the Journal of Experimental Biology in February 1997. The authors explored the influence of atmospheric conditions on animal vocalizations and found that many species choose evenings because the conditions are most favorable for maximizing their chances of being heard over the longest possible distances. So this could mean that the howls for some dogs are to define their territory to others.
Dogs can use vocalization to identify each other too, because they have been shown to be able to discriminate different types of sounds based on which dog is vocalizing and what he is vocalizing about. In a study in 2009 published in Behavioral Processes, researchers showed that dogs could discriminate between a bark to signify a stranger’s presence as well as a bark or howl to express dissatisfaction at being left alone, and also which individual was associated with each sound. Your dog could be howling to classify himself to others.
So if dogs are able to tell which individual is vocalizing, they may be using the howl to advertise their presence for things like courtship and teamwork and to make themselves known. Animals that live and hunt in groups need methods for communication that can cover distance for coordination.
Some studies have suggested that in certain species, long range calls are intended to draw the attention of others of the same species to a threat or signal. A recent article published in Animal Cognition (Dec 2014) showed that chimpanzees were intentionally vocalizing to signal others of a threat (in this case, the presence of a snake). So it is possible that your dog hears the siren and perceives it as a threat signal that he is obligated to pass on to others.
When your dog howls, be patient. He could want others to know that your home is his territory and he is currently in his territory to defend it should the need arise. He also wants to be clear about who he is and to do his part in passing along information about possible threats. He is likely falling back on his instincts to participate in the rituals of his predecessors. So until he can update his status on social media, he will have to keep howling to get his messages across!
