Dogs–The Scoop on Poop


It’s just one dog! Is dog poop really that bad? How about not using a bag and leaving the dog poop to decompose? 

We hear these sorts of comments all the time. The answer? What dogs eat, what their waste carries, and how many dogs visit an area can seriously impact all sorts of ecosystems (including those beautiful woods and parks that EwA surveys). 


What a healthy dog diet actually does to wildlife. Our dogs don’t have the same diet as wild animals. They don’t eat wild grapes, berries, any native plants, or even wild game. They eat processed food designed and enriched to provide our lovely companions with a complete, healthy diet. This food is nutrient-heavy. Nutrients from pet waste (as well as ours, by the way) throw ecosystems out of balance if that dog poop is not picked up and disposed of properly. Nutrient pollution is a major and widespread problem in the U.S. Nutrients in groundwater can be harmful, even at low levels. Groundwater provides drinking water for millions of people, and children are known to be vulnerable to nitrates (a nitrogen-based compound) in drinking water. Excess nitrogen in the atmosphere can impair our ability to breathe and alter the development of plants. An excess of these nutrients can harm the health of forests, soils, and waterways. In many ecosystems, this excess creates conditions that allow invasive weeds to grow and toxic algae blooms to spread in our streams, rivers, and lakes.

Parasites & bacteria galore Another problem with dog poop is that our dogs carry very different bacterial and parasite fauna than wild animals. This fauna is not a problem for dogs –  they evolve with that fauna and are immune to it – but that is not the case for wildlife. Dog waste contains high levels of bacteria that are harmful to wild animals (and people). According to the EPA, one gram of dog waste can contain upwards of 23 million fecal bacteria (supposedly as toxic as an oil spill!). When left unchecked (i.e., not scooped and not disposed of appropriately), elements of that toxic soup can make their way to waterways through erosion and rain, contaminating anywhere they pass through.

Overpooped woods. “It’s just one dog pooping in the woods!” Not really… Our cumulative impact is quite impressive. A few years back, it was reported that about 83 million pet dogs produced about 10.6 million tons of poop every year (across the US), each kilogram or pound adding excess nutrients, foreign parasites, and harmful bacteria to all ecosystems where the waste wasn’t disposed of properly.


🖐🏼 Do you want to help? → Join the EwA Trail Report project. If you want to learn more about EwA’s habitat fragmentation study and see an example of its impact in the case of the Middlesex Fells Reservation in the Greater Boston Area, please read Keeping a Forest Whole, which highlights our work, presented at C*Sci 2023, and NENH23.

More → The Poop Problem: What To Do With 10 Million Tons of Dog Waste (Op-Ed) by Freinkel, S., LiveScience (2014) | Scoop the Poop: It’s Your Environmental Doody (Pun Intended) by Baechler, N. (2018)


1st published on Nov 22nd, 2021 | Revision: Nov. 16th, 2023 | Banner photo: Image by Kevin Phillips from Pixabay | EwA encourages nature enthusiasts to follow proper field and trail ethics, as highlighted in the EwA Wildness Etiquette

Sharing is Caring Spread the Word!

✒️ What you think is important to us. Feel free to engage us and leave a courteous message below. Thanks!

Print Friendly, PDF & Email