Pets vs Wildlife

*Right relations with non-humanimals excludes dominion (zoos, pets, faring, hunting, etc.), but does include stewarding genuinely for their own interests (habitat restoration, sanctuaries, etc.)

*Natural selection” and “human selection”: Natural selection is always for the betterment of the species, while human selection is almost always done for human gains and almost always is not better for that species. The error is not necessarily in having a rescued “pet” the error is in breeding them – any of them.  Ken Damro


The Effect of Dogs On Wildlife

Many people enjoy hiking with their dogs in natural areas, since dogs derive a lot of pleasure from sampling all the scents in such areas, as well as getting some great exercise. Some dog owners delight in seeing their dogs roam free off the leash, since the dogs get even more fun from that.

However, due to the disturbance to wildlife caused by dogs, many parks and preserves have banned them. This page lists some of the reasons behind that ban:

Direct Predation. Even though my experience is that dogs are rarely successful in catching the many birds and squirrels they chase, dogs occasionally directly kill wildlife, or injure the wildlife enough to cause their subsequent death.

Dogs roaming off trail can trample vegetation, and if dogs are numerous they can remove the vegetation in popular areas by trampling, scratching and digging. Trampling is the major effect of hikers and their pets to plants.

Indirect Predation. Even when dogs are unsuccessful in catching the object of their chase, the potential prey has had to expend significant energy in order to save their life. Since in many cases animals are just barely surviving, expenditure of extra energy may push them over the edge to malnutrition and allow other predators to kill them. ..

Both types of predation are severely reduced, but not eliminated, if dogs remain leashed. However the simple fact is that a large percentage of dog owners allow their dogs to be off-leash even when the rules state otherwise. ..

Disease Transmission. It is worth recalling that the primary effect on Native Americans due to European immigration to the Americas was the importation of disease which killed off the majority of the Native Population. Dogs can apparently transmit a number of pathogens to wildlife:

  • Parvovirus affects other canines, and was the source for wolf pup mortality in Glacier National Park area in the early 1990s.
  • Muscle cysts (Sarcocystis spp.) can affect ungulates like deer and elk.
  • Leptospirosis is a bacterial disease that affects the kidneys and urinary tract of most species of mammals.
  • Parasites such as ticks, keds, tapeworms, and fleas are well-known problems in dogs that can be passed to other wildlife.

Many of these pathogens are transmitted through the abundant feces that dogs leave on any trail.

Source: Domestic Dogs in Wildlife Habitats: Effects of Recreation on Rocky Mountain Wildlife.

Competition for Resources. Water is usually the scarcest resource in many places during the summer and fall…

Addition of nitrogen to the soil. Patrick Murphy, a plant ecologist, points out that dog poop adds significant nitrogen to the soil, which encourages the growth of non-native plants at the expense of native plants. (SDUT 12/9/01, E2)

Scent? It has often been said that just the scent left by a dog can affect the behavior of other species. While this certain is plausible, due to the strong importance of scent marking used by animals, apparently this has never been documented. (This does not mean that this is not a problem; simply that it has not been shown to true of false.) See A Review of Mammalian Scent Marking.

  • Dogs decrease the number and diversity of wildlife near the trail. Many people come to the SRP to see animals, so their enjoyment would be directly diminished.
  • Many non-dog owners are immensely bothered when a strange dog comes up to them and starts to smell them at close quarters, or worse, jumps up on them or barks at them. Many dog owners may not even be aware of this, since, after all, dog owners consider this close contact with their dog to be a pleasant experience, and may even think that everyone else enjoys this, too.
  • The presence of dogs would inevitably result in a small number of bad encounters between dogs themselves and between dogs and visitors. Small children are especially in danger from loose dogs, ranging from simply being knocked down by an enthusiastic dog to being bitten or seriously harmed.

In case dog owners reading this feel that the above information is simply the opinion of someone who does not like dogs, it is worth noting that I personally have hiked many miles with my dog in public areas where dogs are allowed. ..

Why No Pets?

With a goal of healing habitat for every free animal from butterflies to bears, there is a conflict between wildlife and pets. Here are a couple examples of vegans explaining why they prioritize wildlife:
*Light Morning Community in the Blue Ridge Mountains writes:
Pets We ask that you leave your pets at home. We consider these 150 acres to be a wildlife sanctuary and have no roaming cats or dogs ourselves. Nor do we allow hunting. The other creatures with whom we share this land are treated with courtesy and respect, even those who are tempted by our garden and orchard or who ( like our occasional poisonous snakes) demand special awareness. The land’s a sanctuary for us all.
*Zim Zam on a smaller piece of land in Asheville NC writes on the many aspects behind their ‘no pet’ policy, including ethics:

Some people have reacted very strongly toward this statement on animal ownership and in particular our desire to have a pet free community. Not everyone who lives here shares the same feelings about animal ownership and pets. As a community however, we have made the choice to have no animal ownership within the community. It seems to us that there is a place for a community which does not have any animal ownership. Those who want to be involved in animal husbandry have many communities where they go. Those who want to own pets have many communities where they can go. Those who wish to live in a community with no animal ownership and no pets have few choices. Zim Zam will be one of those places.

The following statement was written by Cicada and primarily conveys his position with regards to animal ownership. It is not saying that people should get of their pets. There are so many dependent animals. They need care. This statement is a statement which is challenging to many people’s way of thinking about human/non-human relationships. When people first began to make statements against human slavery, such statements would sound crazy to most people in the culture because they were outside of the normal way of thinking about human relationships that involved slaves. Slavery was accepted as a part of society and to challenge its validity was considered by many to be crazy. This is a statement challenging the accepted paradigms of human/non-human animal relationships. I believe that while in today’s context it may sound crazy, in the future, the current paradigms of animal husbandry and pet ownership will be viewed as immoral and as destructive to our potential for all beings to grow as an interconnected network of living souls.
This doesn’t mean that if you own a non-human animal that I think you should get rid of it. Each one of us has our own way of relating to other beings in our environment. It is for each one of us to determine whether the relationships we are creating in our lives are ones which are healthy for us and our fellow beings

Right to Free Agency

No animal ownership is a philosophy which recognizes the right of all animals to exist for their own purposes and to lead their own lives. Animal ownership is the enslavement of non-human animals in order to serve the desires of humans. Many people react strongly when the word “enslavement” is used to describe human/animal relationships. Many of the arguments animal owners use in response bear an incredible resemblance to those used by defenders of human slavery. For example: The animals’ dependency on their human owners is such that “liberating” them is actually a disservice because they would not be able to survive in the wild. Many slave owners had a similar feeling about human slaves. But it is not our right to make such decisions for other animals.
This said, I recognize that the world is far from ideal. Not only are many “liberated” animals not able to survive on their own in the wild, there may not be a “wild” into which they can be set free. Domesticated animals no longer have any natural ecosystem to which they properly belong. These are issues which have no easy answers. I respect and honor those individuals who choose to care for animals which have no place to be free (this includes most “pets”), those who attempt to rehabilitate wild animals and those who give animals sanctuary.


A friend to me wrote:“But why no pets? Pets can mean companionship rather than ownership.”
There are many reasons why we as a community have made this choice.


We desire to have a community which is in as close to a direct relationship with the “wild” world as possible. We do not want to discourage the presence of wildlife on the land. We would desire to have much of the land of any future rural component to be maintained as a wilderness preserve. For the community to be a wilderness preserve forbids the presence of pets whose interactions would tend to diminish the presence of wildlife on the community land. Specifically, dogs chase away many animals and their presence discourages the presence of wild canine species such as fox, coyote and wolf. Cats diminish the presence and diversity of animals such as birds, lizards and rodents. In our urban space, having as much wildlife as possible within the limits accorded by our situation is desired as well. Our land is certified by the World Wildlife Federation as a Backyard Wildlife Habitat.
The fact of dependency by the pet upon the “owner” is fundamental to many pet relationships. This keeps the animal from being a free agent. The statements by animal owners that they don’t actually own their animals does not recognize the degree to which they are required by our society to take responsibility for the whereabouts and actions of the animal. In most situations, the human pet owner controls when and where their pet has access to the outdoors and the pet’s freedom to go where it wants when it wants is limited.
Even if your pet is allowed to run “free” society says you are repsonsible for the actions of your pet. If a dog is living on my land and it goes over to a neighbor’s land and digs up their garden, I am considered responsible. If a fox is living on my land and does the same thing, the fox is responsible.
If an animal cannot provide food for itself, but is dependent upon a human to provide its sustainance, it is not truely free to go where it wishes. The animal does not know how to provide for itself, so it returns to the human because it knows that is where it can get food. It knows no other way to exist. This is not freedom, it is slavery.
Companionship is an honorable relationship to share with another being of whatever species. It is unfortunate that because of the number of humans and domesticated animals who exist that these types of relationships result in human ownership of the non-human. Ideally there could be companionship relationships which would not be rooted in ownership and dependency. Certainly there are people who have companionship relationships with non-humans which are as healthy as such relationships can be within the context of our current culture. This does not change the fact that the non-human in the relationship does not have free agency. Ultimately, humans will need to free their animal companions in order for all beings on the planet, including ourselves, to have the freedom to develop our full potential as an interconnected network of living beings.

Being Vegan

Zim Zam is a vegan community. While it is possible to formulate vegan foods for dogs and cats, these animals are physiologically carnivorous animals. Cats are not vegan. They will catch and eat other animals. Dogs are not vegan. Many dogs may not have the ability to actually catch other animals, but they will try. Animal owners make choices about what to feed their animals and so can impose veganism on a pet. But this is not a choice being made by the animal for itself. The humans who live at Zim Zam are choosing to live in a vegan community. A pet would not be freely making that choice for itself.
Lola has an allergy to animal hair and dander which forbids the presence of pets within the buildings of the community. Other people with similar allergies will be able to come and participate in Zim Zam without their allergies being set off.
Finally, with the overpopulation of humans and domesticated animals impacting nature, there is one difference between adopting pets & adopting children.  The ‘My pet is a rescue dog’ & telling the sad story of how the dog had been neglected and/or abused’ is extremely popular. Popular to the point where the pet industry is skyrocketing, likely increasing the number of pets exponentially {and the amount of destruction they cause to natural environments dislocating wildlife}. A decision to ‘rescue’ a suffering domesticated animal today is a decision to harm wildlife. On the other hand, ‘rescuing’ orphaned kids is no where near as popular, and certainly doesn’t drive up the human population numbers like the pet industry does the domesticated dog numbers. Ironically, kids who are adopted are likely to breed less. Pets who are adopted drive up popularity making the pet breeding industry more lucrative.

If you love your parks, you’ll leash your dog

Originally published August 11, 2005 in the Seattle Times

Forgive the pet metaphor, but the people of Seattle have got to stop pussyfooting around about dogs. Seattle boasts some of the nation’s…

By Ann Hedreen

Forgive the pet metaphor, but the people of Seattle have got to stop pussyfooting around about dogs.

Seattle boasts some of the nation’s most progressive dog-ownership laws. We have a leash law that allows owners to take their dogs just about anywhere. We have nine off-leash areas where owners can run their dogs freely, and we’re about to have two more. We have a successful scoop-it campaign that makes our streets far more foot-friendly than many cities (been to Paris lately?).

Seattle also is endowed with some of the nation’s most beautiful parks, including half a dozen pockets of true urban wilderness, giving dog owners an endless supply of beautiful places to exercise themselves and their pets.

But something’s happening here that could upset the whole idyllic picture. Our parks and the people who visit them are at risk because of a growing minority of dog owners who are choosing to break the leash law.

Over the 15 years I’ve been running and walking in Seward Park, I have seen more and more dog owners choose to run their dogs off the leash. They know our animal-control agency is woefully understaffed and it’s highly unlikely they’ll ever get a $54 ticket. They know that there is an off-leash dog area a half-mile away at Genesee Park.

What they may not know is that their dogs are trampling native plants, allowing invasive ivy to take over the forest floor and slowly choke some of Seattle’s oldest trees. They may not know that the city, with the help of several small volunteer organizations like the Friends of Seward Park, spends more and more time and money every year trying to save the parks from their carelessness.

They may also not know that no matter how well-behaved their dog is and no matter what breed, their dog can terrify people who don’t know from a hundred yards away how friendly and harmless it is. And their dog, even if it has never misbehaved before, can bite someone, and when it happens, it happens in the blink of an eye.

The American Veterinary Medical Association estimates that nationwide, 4.7 million people a year are bitten by dogs. Eight hundred thousand require medical attention. Injury rates are highest among children ages 5-9. The younger the child, the more likely they are to be bitten on the head, face or neck.

The Seattle Animal Shelter’s executive director, Don Jordan, says that our city averages about 300 reported dog bites per year and one to two reports of aggressive or menacing dogs per day, but that many bites and incidents go unreported.

On the list of breeds that account for most of the reported dog bites in Seattle are some that you would expect, such as pit bulls, and others you might not: Labs, retrievers and spaniels.

“This isn’t a dog problem, this is a people problem,” Jordan told me. “Dog owners need to behave themselves. Having a dog off-leash is not an entitlement.”

Dave Patterson, head of the Division of Rehabilitation Psychology at the University of Washington School of Medicine and Harborview Medical Center, concurs, noting that, especially for children, the trauma of a severe dog bite carries with it a greater risk of long-term post-traumatic-stress disorder than most other kinds of trauma.

“There’s a primal brain response to the notion of being attacked,” Patterson explained. “These attacks can create phobias in children that may last for the rest of their lives.”

It’s time to protect our children and our parks. We need posters, yard signs, bumper stickers and T-shirts that bear a simple message: I LOVE OUR PARKS. I LEASH MY DOG.

We need Seattle’s many conservation groups — the Mountaineers, the Sierra Club, the Audubon Society, the National Wildlife Federation — to get behind an education campaign.

And if education campaigns, generous leash laws and off-leash areas don’t work, then maybe it’s time to create “off-dog” areas where people can play, picnic, walk and run freely, without fear. At the same time, we can give old-growth trees and open meadows freedom from dog abuse.

Three decades ago, Seattle set an example for the nation when it embraced recycling. We can do this, too. We can be a city that is dog-friendly and park-friendly.

Ann Hedreen is a filmmaker and writer who lives in Seattle.

The impact of free-ranging domestic cats on wildlife of the US

Anthropogenic threats, such as collisions with man-made structures, vehicles, poisoning and predation by domestic pets, combine to kill billions of wildlife annually. Free-ranging domestic cats have been introduced globally and have contributed to multiple wildlife extinctions on islands. The magnitude of mortality they cause in mainland areas remains speculative, with large-scale estimates based on non-systematic analyses and little consideration of scientific data. Here we conduct a systematic review and quantitatively estimate mortality caused by cats in the United States. We estimate that free-ranging domestic cats kill 1.3–4.0 billion birds and 6.3–22.3 billion mammals annually. Un-owned cats, as opposed to owned pets, cause the majority of this mortality. Our findings suggest that free-ranging cats cause substantially greater wildlife mortality than previously thought and are likely the single greatest source of anthropogenic mortality for US birds and mammals. Scientifically sound conservation and policy intervention is needed to reduce this impact.

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Download references


  1. Migratory Bird Center, Smithsonian Conservation Biology Institute, National Zoological Park, P.O. Box 37012 MRC 5503, Washington, District of Columbia 20013, USA

    • Scott R. Loss &
    • Peter P. Marra
  2. U.S. Fish and Wildlife Service, Division of Migratory Birds, Midwest Regional Office, 3815 American Boulevard East, Bloomington, Minnesota 20013, USA

    • Tom Will


S.R.L. designed the study, collected and analysed data, and wrote the paper. T.W. and P.P.M. designed the study and contributed to paper revisions. All authors discussed the results and commented on the manuscript.

Competing financial interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to:


Eco-footprint or pawprint?

Domestic animals contribute to our carbon footprint, mainly due to their meat-based diet. A dramatic increase in domestic dog ownership in the world’s most populous country could lead to an increase in global CO2 emissions, experts warn.

In 2014, around seven percent of Chinese households – around 30 million – owned a dog, according to figures by Euromonitor. That compares to one in five homes in the EU and almost 50 percent of all US households. Experts warn it won’t be long before China’s ‘faithful friends’ equal those numbers in the West.

“For everyone in the world to have an American lifestyle, we would need seven planets, and three to live as Europeans,” Dabo Guan, professor at the University of East Anglia’s School of International Development, in the UK, told DW.

“If every urban Chinese person would have a Western lifestyle, the CO2 emissions in the country would double by 2030,” he added.

Although controversial, the idea of dogs as polluters started taking shape around 2009, with the publication of the book “Time to Eat the Dog? The Real Guide to Sustainable Living,” by Brenda and Robert Vale.

The authors proposed that a medium-sized dog has twice the ecological footprint of a 4×4-style car.

Blame the pets?

John Barrett, a professor at the University of Leeds’ School of Earth and Environment, agreed with the authors – despite being a dog lover himself. Barrett told DW that the impact of pets on the environment is quite noticeable due to their meat-based diet –

Therefore, a dramatic rise in the global dog population would inevitably lead to an increase in greenhouse gas emissions, he warned.