Does Trash Predict Rats? New York Complaints by Zip Code
Trash complaints and rat complaints move together across New York’s zip codes, with a rank correlation of 0.73, but total complaint volume of any kind tracks rat complaints slightly more closely still, at 0.76. Most of the apparent link is that some neighbourhoods report everything more than others. Strip that out and a weaker relationship survives at 0.33, which is the honest size of the trash effect in this data. Missed collections barely register at 0.10.
Every rat story eventually arrives at garbage. The claim is plausible, it is what the biology would predict, and city officials repeat it whenever a new waste containerisation rule is announced. We tested it on 153 New York zip codes using a year of complaint records, and the result is more qualified than either side of that argument usually allows.
What the raw numbers say
Across 153 zip codes with enough complaint volume to analyse, rodent complaints and dirty condition complaints have a rank correlation of 0.73. That is a strong relationship. Ranked by trash complaints, a zip code’s position predicts its rat complaint position fairly well.
The problem is the control. Ranked by total 311 complaints of every kind, from noise to potholes to heat, a zip code’s position predicts its rat complaint position slightly better, at 0.76. Whatever is driving the trash relationship is mostly not specific to trash.
| Compared with rodent complaints | Rank correlation | Raw correlation |
|---|---|---|
| All 311 complaints | 0.76 | 0.38 |
| Dirty condition complaints | 0.73 | 0.63 |
| Dirty conditions, as a share of local complaints | 0.33 | 0.27 |
| Missed collection complaints | 0.19 | 0.10 |
Across 153 New York zip codes with at least 500 total service requests and 25 rodent complaints in 2025. Rank correlation compares positions in the order; raw correlation compares the counts themselves.
Removing the neighbourhoods that complain more
A zip code that files 50,000 service requests a year will file more of every category than one that files 5,000. That is partly population, partly housing density, partly the age profile and civic habits of the people living there, and partly how much the city has trained a neighbourhood to expect a response.
The correction is to compare shares rather than counts: rodent complaints per 1,000 of that zip code’s total complaints against dirty condition complaints per 1,000 of the same total. This asks whether, among places that complain a lot, the ones complaining disproportionately about trash also complain disproportionately about rats.
They do, but weakly. The rank correlation falls from 0.73 to 0.33. That is a real relationship and not a trivial one, and it is far from the deterministic link implied by the phrase “rats follow garbage”.
Missed collections are not the driver
Missed collection complaints, where the truck did not come, correlate with rodent complaints at 0.10 on the raw counts and 0.19 by rank, the weakest relationship of anything we tested. If uncollected refuse sitting out beyond its schedule were the mechanism, this is where it would show, and it does not.
The more plausible reading is that dirty conditions, which covers accumulated waste, overflowing receptacles and improperly stored refuse, describes a persistent state of a block, while a missed collection is a one-off event. Persistent conditions support a population; a delayed truck does not.
The zip codes at the top
| Zip | Rodent complaints | Dirty condition complaints | All 311 complaints |
|---|---|---|---|
| 10035 | 1,418 | 597 | 17,684 |
| 10452 | 753 | 1,364 | 51,558 |
| 11221 | 680 | 902 | 35,479 |
| 11226 | 677 | 1,026 | 54,392 |
| 11238 | 653 | 845 | 32,445 |
The five zip codes with the most rodent complaints in 2025.
The top row is the argument in miniature. Zip 10035, covering East Harlem, logged the most rodent complaints in the city, 1,418, on a relatively modest 17,684 total complaints and fewer dirty condition complaints than any of the four zip codes below it. It is the most rat-dominated zip code in New York’s complaint record and it is not the most trash-dominated one. Meanwhile 11226 in Brooklyn files three times as many complaints overall and fewer rodent complaints.
What we are actually measuring
Complaint data measures reporting behaviour, and rats are the intermediate variable nobody observes directly. A block with rats and residents who never call 311 is invisible here. So is a block where a landlord deals with the problem privately, which is the situation most of this industry actually works in.
This cuts both ways for the trash argument. The correlation could understate a real biological relationship, because reporting noise dilutes it. It could also overstate it, if the kind of neighbourhood that generates visible waste is also the kind that generates 311 calls for reasons unconnected to either.
What the analysis does establish is narrower and still useful: within this data, sanitation complaint volume is a weak predictor of rodent complaint volume once neighbourhood reporting intensity is accounted for, and missed collections are close to useless as a predictor. Anyone forecasting rodent pressure from waste metrics should expect a loose relationship rather than a tight one.
For what happens after a complaint is filed, see our analysis of city response times, and for the longer trend in complaint volumes in both New York and Chicago, our 311 rat complaint data. The building-level picture of who is actually cited sits in our housing violation analysis.
How we did this
We counted 2025 service requests by incident zip code for four categories in the New York 311 dataset: Rodent, Dirty Condition, Missed Collection, and all complaint types combined. We kept zip codes with at least 500 total requests and at least 25 rodent complaints, leaving 153, which excludes commercial and low-population zip codes where small counts produce unstable ratios.
We report both Pearson correlation on the counts and Spearman rank correlation, because complaint counts are heavily skewed and a handful of very high-volume zip codes otherwise dominate the Pearson figure. The normalised version divides each category by that zip code’s total complaints. Correlation is not causation, and none of these figures support a claim about direction.
Frequently asked questions
Does trash cause rats?
Accessible food waste supports rodent populations, which is not in dispute biologically. What this complaint data shows is weaker than that claim implies: trash complaints and rat complaints correlate at 0.73 across New York zip codes, but total complaint volume of any kind correlates at 0.76, and once neighbourhood reporting intensity is removed the trash relationship falls to 0.33.
Which New York zip code has the most rat complaints?
Zip 10035, covering East Harlem, with 1,418 rodent complaints in 2025. It is notable for having fewer dirty condition complaints than several zip codes with far fewer rat complaints, which cuts against a simple trash explanation.
Do missed rubbish collections lead to rats?
Not detectably in this data. Missed collection complaints correlate with rodent complaints at 0.10 on raw counts, and 0.19 by rank, across 153 zip codes. Persistent dirty conditions show a relationship where one-off missed collections do not, which is consistent with populations responding to sustained food availability rather than isolated delays.
Can 311 complaints measure how many rats there are?
No. Complaint data measures who calls the city, which varies with tenure, language, age, trust in government and prior experience of getting a response. Two blocks with identical rodent populations can produce very different complaint counts, so these figures describe reporting patterns and should be read as a proxy with known bias.
Sources
- NYC Open Data, 311 Service Requests from 2010 to Present, complaint types Rodent, Dirty Condition and Missed Collection, calendar year 2025. data.cityofnewyork.us
- Analysis by The Pest Control Brief, September 2026.
