What I learned from 20,000 dog poops

Source: https://www.flickr.com/photos/scottlowe/3931408440/

I beg to move,

That this House

has considered dog fouling.

Westminster Hall Debate, 14 March 2017


When working with data that you didn’t set out to gather you have to be careful to think about what the data actually means, rather than what it seems to be saying. As an example, one of the “interesting” side effects of FixMyStreet is a database of places people have reported dog poop (or “dog fouling” as it tends to be called academically). We now have over 20,000 locations across the UK where nature’s call has both been heard, and reported.

My first thought when learning about this data was “that’s a lot of dog poop!” but it turns out 20,000 dog poops is not a lot of dog poop at all. There are an estimated 8.5 million dogs in the UK, assuming (on average) each one poops once a day, they’ll produce over 3.1 BILLION poops a year.

So actually, 20,000 poops over nine years is nothing compared to the amount of pooping going on. But just because our data is a drop in the bucket doesn’t mean we can’t learn interesting things from it.

Questions, So Many Questions

The first question to ask is if we have a representative sample of where all this dog fouling is going on. The answer, sadly, is no. But the reasons for that answer raise further questions — which is interesting!

When you map dog poo complaints in England against the area’s position on the Index of Multiple Deprivation [1], you get this:

This tells us that reports about dog poop are roughly parabolic — there are more in areas in the middle than those that are either very deprived or very not.

This is interesting because when Clean Up Britain actually went out into the world and checked [p.14], they found this:

This graph tells a very different story, where dog fouling gets worse the more deprived the area. But why is this? And why doesn’t our data tell the same story?

Going through the research on (and history of) dog poop suggests an understanding of dog fouling as a social rather than logistic problem. In this light we can make sense of the relationship between dog poop and multiple deprivation (as well as why that relationship doesn’t cleanly appear in FixMyStreet data) as the result of social factors affecting the owners of dogs, rather than just environmental factors.

A history of poop on the streets

To gain some perspective on twenty-thousand 21st century poops, it’s good to think about the absence of dog poop as a problem in mid-nineteenth century London. At this time dog poop (called “pure” because of its “cleansing and purifying properties”) was in demand by tanneries for drying out and changing the natural smell of the animal skin. To meet this demand “pure” finders would roam the streets — collecting their product and selling it on. This fits in the web of private waste collection services recycling the ‘dust’ of London. This trade was lucrative enough to support itself and turn a profit in the first half of the 19th century, and only became a net drain on parishes in the second half of the century(p. 8).

In Henry Meyhew’s London Labour and the London poor he wrote that:

The pure-finders always carry a handle basket, generally with a cover, to hide the contents, and have their right hand covered with a black leather glove ; many of them, however, dispense with the glove, as they say it is much easier to wash their hands than to keep the glove fit for use.[…]
The pure-finders meet with a ready market for all the dogs’-dung they are able to collect, at the numerous tanyards in Bermondsey, where they sell it by the stable-bucket full, and get from 8d. To 10d. per bucket, and sometimes 1s. and 1s. 2.d. for it, according to the quality.

As different tanneries had preferences for different consistencies, some finders would cheat and add “mortar broken away from old walls” to change the volume or colour of their product.

This was an important source of income for these collectors. Mayhew estimates about 200–300 people were employed in the 1840s supplying the thirty or so tanyards of Bermondsey. In an interview with a woman who had been a pure-collector for fifteen years, she talked about how the market had changed over that time:

If we only gathered a pail-full in the day, we could live very well; but we could do much more than that, for there wasn’t near so many at the business then, and the Pure was easier to be had. For my part I can’t tell where all the poor creatures have come from of late years; the world seems growing worse and worse every day. They have pulled down the price of Pure, that’s certain; but the poor things must do something, they can’t starve while there’s anything to be got.

In this way the dog poop problem solved itself, via a need in the marketplace and a supply of desperate labour. The lack of dog poo in the streets reflected that dark dynamic at work.

Clean Streets, Clean Societies

The next century saw the world of the pure-finders vanish and a new one emerge where dog poop was Public Enemy #1. Recycling waste was no longer profitable and cities were developing higher standards. Chris Pearson, looking at Paris (which similarly had an industry based around its dog droppings), argues that cities were starting to get clean enough for dogs to stand out as a problem:

The demise of horse drawn-transportation from its peak in the 1880s and 1890s meant that Paris produced far less manure and sludge by the 1920s. As one writer in La Presse Medicale formulated the problem in 1929, the disappearance of the city’s horses had exposed the ‘true horror’ of dog excrement. Cleansed, paved and tarmacked roads constituted a “blank canvas” upon which dog excrement could be “discovered” and framed as a public hygiene problem.

In the 1920s London bye-laws started to be passed fining people who permitted their dog to “deposit its excrement upon the public footway” and this was a matter to be discussed in the journal Public Health. Emphasis on the health hazard became more and more explicit as time went on. From the 1961 report of the Kensington Medical Officer of Health:

While it has been shown that dogs can carry and excrete germs capable of producing illness in man, it is seldom that cases of human disease can positively be related to infections originating from this source. Nevertheless, such instances do occur and the potential risk cannot be ignored. Certainly dog filth is an attraction to flies and blowflies, with consequent possibilities of conveyance of infection.

While also suggesting that this was a side issue to the more aesthetic problems:

The main objection, however, to the fouling of pavements and grass verges by dog excreta is the nauseating revulsion, embarrassment and distress caused by chance pollution of shoes, clothing, mats and carpets, necessitating disgusting and time-consuming cleansing operations.

In 1971 the British Medical Journal asked ‘Why do we let dogs foul our streets?’ and suggested that new medical knowledge added an urgency to this:

Perhaps the principal reason why dogs aroused little concern over health in the past is that, of the helminthic infections which they transmit, hydatid disease was the best known, yet it was rarely transmitted in Britain. Moreover, of human toxocariasis virtually nothing was known until about 12 years ago. […]
Developed communities have long been conscious of the need for high standards of hygiene for human excreta. Given what we now know about toxocariasis, should we not demand the same for dogs?

Dog droppings had transitioned from being a public resource for private gain (‘Pure’) to being a health hazard (‘excreta’, ‘filth’) that blights communities — and a matter of personal responsibility for the owner.

The Long Pooper-Scooper of the Law

This positioning of dog poop as a mix of public hazard and private irresponsibility makes it a good match for local government. Practically though, it is a difficult problem to address. A 1928 report of a bye-law in Paddington noted that “[o]ne minor difficulty in enforcing the bye-law is that an offender cannot be compelled to divulge his identity and cannot be given in charge as the police do not enforce the bye-law”. I think you can reasonably argue this is actually quite a big problem that makes legal coercion tricky.

The last thirty years have seen numerous attempts to strengthen the hand of scoopers against the poopers. The Litter (Animal Droppings) Order 1991 extended provisions of the Environmental Protection Act 1990 to cover dog faeces. A criminal offence was created with the Dogs (Fouling of Land) Act 1996. This was taken further by the Clean Neighbourhoods and Environment Act 2005 with Dog Control Orders and — pause for breath — these are in turn becoming Public Spaces Protection Orders via the Anti-Social Behaviour, Crime and Policing Act 2014.

Many of these empower local authorities to attempt to control dog fouling in certain public locations through fines — with possible means of achieving this becoming increasingly broad. In 2012, West Dunbartonshire Council started spraying dog poo pink to shame the owners into picking it up. In 2016 Barking [2] and Dagenham tried a pilot project where they offered free DNA registration for dogs — and this database would in turn be used to check for matches against the DNA of offending dropping.

Local councils are keen to enlist the public’s help in catching offenders — advice pages on council websites often go beyond instructions to dog owners on their responsibilities to imploring the public to get in touch. Wyre Forest’s website says:

“Don’t stand by and let it happen. Make a note of their details and let us know. If you know a particular person with a certain breed of dog who visits an area or park at a regular time of day give us the details.”

Others like Tamworth ask for reports to let the council work out “hot spots to support future patrols and campaigns”. Sometimes it is even directly stated the Council will take responsibility for sorting out the problem. Croydon Council say that “Once reported, we aim to remove it within five working days” and Epsom and Ewell Borough Council write “Report it and we’ll remove it”. When reports feed to councils through FixMyStreet, they may be interpreted to different ends.

From fines and psychological pressures to DNA labs and sending people out to pick it up — 21st century local government is now actively involved in the problem of dog poop. And as 20,000 reports attest — they have willing allies in the general public.

Why People Pick Up

As the modern problem of dog poop has an emphasis on the personal responsibility of the owner, understanding why people do/do not pick up their dog’s poop is useful information. In the mid-nineties Webley and Siviter spent 120 hours hanging around parks in winter waiting for dog owners to let their dogs poop — and then sprang a six-page questionnaire on them to find out what was going on (psychology is a glamorous field).

This patience had interesting results. They found that the “irresponsible” group (who did not pick up the poop) were much more likely to see it as natural waste, highlighted that it was inherently biodegradable and that bylaws were overly restrictive. However, they also believed more than the “responsible” group that it was “unpleasant to clear up” — suggesting an element of self-justification to this principled stance. Another useful finding was that most dog owners they observed (59%) did clean up, with those that don’t having an outsized effect on public perception because it can hang around for weeks after.[3]

In 2010, Lowe and colleagues performed an audit of some popular dog walking paths in Lancashire to see how the layout of the land and availability of bins affected the visibility of dog waste. Their findings suggested the picture wasn’t simple, with comparable low rates of dog poop on a path with lots of bins to a path with almost no bins.

This study found that incidents of dog poop seemed to be related to the geography of the area and the ability of others to observe (and judge). On one path the combination of long-distance visibility and no bins seemed to lead to people bagging their dogs’ poop — but then discarding the bag (researchers found 269 bags in a 1km path). As bagged poops are a greater environmental hazard (they take longer to bio-degrade and judged as being more objectionable to see than raw dog poop) — this reflects social pressure without accompanying infrastructure can lead to perverse outcomes.

Why People Complain

The key insight from these studies is that deciding whether or not to pick up dog poop is a social act and depends on how people think they’ll be judged. This leads to a framework that makes the FixMyStreet data more understandable. When looking at a report of dog poop in an area the key bit of information isn’t “there was dog poop here” but “someone complained about dog poop here”.

As it turns out the field of dog poop research includes some investigation about what is actually going on when people complain about dog poop in their community — the drive to report is moderated through how people feel about their neighbourhood. Derges and colleagues (2012) found that complaints about dog poop were often “expressions of social and environmental neglect [in communities] where neighbours were estranged from one another”. The presence of dog poop makes people feel “disgust” — so as a symbol it will often be brought up in combination with other complaints as a way of expressing a feeling of both disgust for their environment and neglect by authority. Importantly, this might be out of proportion to any actual dog poop problem. According to this theory, complaints about dog poop are at least in part about wider beliefs in the state of your neighbourhood.

Something I didn’t quite know how to interpret was that around 10% of our dog poop reports include a picture. I haven’t done a comprehensive analysis of these, but I did look through a few and… they’re pretty much what you’d expect. Thinking within in the framework of disgust/community cohesion including a picture actually makes a lot of sense. If a dog poop complaint is an expression of disgust and a statement about failing authority then taking and sending a picture is that a hundred times over. When people upload a picture of dog poop to the internet — it is meant to be a bit shocking. This is weaponised disgust in the face of seeming neglect from authority.

Moving outside of academia, this post on South Poop (a website raising awareness of ‘orphan dog poop’ in Chicago’s South Loop) makes the suggestion that sanitation code complaints about dog poop in Chicago are essentially used as tools for people to complain about their neighbours. If true, this is a fascinating low-level way of using the state for score-settling, and again suggests a class of dog poop complaint that is more about community cohesion than about dogs.

Social Cohesion

So returning to our two graphs, why does dog poop get worse in more deprived areas? And why doesn’t FixMyStreet reflect that?

One reason we would expect more dog poop in the most deprived areas is that the most deprived areas are more urban. Taking the same IMD deciles and using the ONS’s RUC categories to apply a eight point ‘ruralness’ scale (where 1 is ‘Urban major conurbation’ and 8 is ‘Rural village and dispersed in a sparse setting’) lets us see the average ‘ruralness’ of each decile. While this reflects that deprivation is spread across urban and rural areas — the most deprived areas tend to be more urban.

As urban areas have less natural places to dispose of dog waste (green spaces, gardens), and the most deprived areas are more urban, we would expect the most deprived areas to have more dog poop.[4] We also know that measures that contribute to IMD scores (such as like crime levels) are related to trust and social cohesion in an area.[5] When social cohesion is lower, we would expect more actual dog poop because owners feel less surveyed and are less concerned with the opinion of neighbours. The real world increase reported by the Keep Britain Tidy survey supports these relationships.

The drop off in our reported data compared to the real world can be explained by features of the general model for understanding FixMyStreet reports — some measures of deprivation are correlated with increased reports (because they relate to more problems) and others with decreased reports (because they hurt the ability or inclination of people to report). We would also expect areas with worse deprivation to have less reports because of disengagement with civic structures.

Quickly checking the English dog poop data (so only 17,103 dog poops) against the same model confirms that significant relationships exist for the same deprivation indexes as the global dataset (with the largest effect size being for health deprivation — as health deprivation in an area goes up, reports of dog poop increase).

What this tells us is that our dog poop data (and probably our data more generally) suffers from a clip at the extreme end of deprivation. We’re not getting as many reports as the physical survey would suggest and so our data has very real limits in identifying the areas worse affected by a problem.

If you used this data to conclude the most deprived areas had a similar dog poop problem to the least deprived areas you would be wrong. Because we have an independent source of the real world rate of problems, we can see there is a mismatch between distribution in reports and reality. Using this independent data of ‘actual problems’ for one of our categories makes us more aware that there is negative pressure on reports in highly deprived areas.

The relationship between society and dog poop speaks to wider stories about our changing attitudes to urban environments, and how we do (or do not) relate to each other in these spaces. The actual dog is almost incidental — dog poop is a people story.

Notes:

[1]: An index that combines thirty-seven indicators from seven domains (income, health, crime, etc) to provide a single figure for an area that is indicative of its level of deprivation relative to other areas.

[2]: Heh.

[3]: The phrase “unsystematic observation suggests about 2 weeks [for it to degrade]” paints an image of the researcher making a daily observation while on the way to hide in the bushes and wait for new dogs to poop. Not all heroes wear a cape, etc.

[4]: This is a relative thing. Rural areas still have problems with bagged dog poo (“the ghastly dog poo bauble” hanging from branches — as MP Anne Main put it). There is also a risk to the health of cows from dog fouling in farmland — so there are unique rural dog poo problems.

[5]: Ross et al. found “People who report living in neighborhoods with high levels of crime, vandalism, graffiti, danger, noise, and drugs are more mistrusting. The sense of powerlessness, which is common in such neighborhoods, amplifies the effect of neighborhood disorder on mistrust.”