Sorry, but your good boy might not be such a good boy after all. Conservationists are increasingly worried about the effects our furry best friends are having on the environment – and the animals in it.

A study published this week found that humans are directly responsible for the death of more than a quarter of land vertebrates worldwide. But our pets are not much better. According to a BBC News article, scientists are now saying that dogs have already contributed to the extinction of almost a dozen species, including the Hawaiian rail. Dozens more are at risk. That includes 30 listed as critically endangered and a further 71 listed as endangered on the IUCN Red List

In 2016, researchers found there were as many as 28 to 30 threatened species facing intense pressure from our canine friends in each of the following geographic regions: South-East Asia, South America, Central America, and the Caribbean.

As a result, their study, published in the Proceedings of the National Academy of Sciences, puts doggos at number 3 in a ranking of the worst human-introduced mammalian predator – just behind cats and rats. Their crimes? Hunting and harassing wild animals, transmitting disease, disrupting the environment, and competing for resources.

In other instances, they are causing problems by interbreeding with wild species. Take, as an example, free-roaming dogs in Europe, who have been known to cozy up with wild wolves. 

Dogs (or rather, wolves) were the first animal to be domesticated, a process that took place between 15,000 and 50,000 years ago. Since then, the number of humans and pups have escalated. There are approximately 1 billion domestic dogs (feral and homebound) alive today. Experts predict more in the future.  

So, what do pet owners think about their dogs' destructive ways? Researchers assessed public attitudes towards dog-management strategies to control free-roaming dogs in southern Chile – their findings were recently published in the Journal of Environmental Management. 

They found that the majority of dog owners let their dogs off the leash to roam freely at least some of the time and were not too concerned about the effect on the local wildlife population. The respondents were, however, more concerned about dogs attacking livestock than they were about them attacking wild animals. 

Species also matters. Forty percent of those asked didn't think there needed to be any ramifications when the attacked animal was a fox. In comparison, 88 percent supported some form of action (fines, eliminating the problem dog, etcetera) when the attacked creature was a pudu (the world's smallest deer).

So what to do? In a piece for The Conversation in 2017, experts advised, "Given the close relationship between humans and dogs, community engagement should form the basis of any management program.

"More research is needed to get a better picture of the scale of the problem, and of how dogs interact with other threats such as habitat loss. Such actions are critically important for ensuring the conservation of wildlife threatened by dogs around the world."