Geospatial Analytics Lab
Location Intelligence & Maps
Christy Rupp artwork
Vanessa Mateus, NYC May 2018
The NYC311 Service Requests can be accessed through the NYC Open Data Portal.
The Rodent Complaint data used comprise data from January 2013 to April 2018 (63 months, 91,669 records with Lat/Long coordinates) and is subdivided into 4 classes:
"Rat sightings" (54%),"Mouse sightings" (15%) and "Signs of Rodents" ( 9%) and "Conditions attracting rodents" aka garbage (22%).
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1. Rodent complaints, by type.
2. NYC311 Rodent complaint, service usage trend.
3. Where are rodent-related complaints spotted?
Locations where Rodents were spotted and reported, from January 2013 to March 2018 (63 months). NYC Community Districts in yellow. Spatio-temporal trends and patterns.
Cumulative - points are aggregated over time (2013-18)
Complaits by Month (2013-18)
Data Source: NYC 311 Service Requests. Complaint Type: Rodent. Descriptor: Rat Sighting, Mouse Sighting and Signs of Rodents. Dates: Jan 2013 to Mar 2018 (63 months, all rodent records with Lat/Long).
The Rodent Density Map divides the NYC area into Rodent Severity ranks (9 very high - 2 low), depending on the number and proximity of each complaint.
The density analysis was based on the Kernel algorithm; 63 months of data and 71,590 complaint points were included.
Data: NYC311 Rodent Complaints from 2013 to April 2018 (63 months, N=71,590) includes "Rat sightings" (49,727), "Mouse sightings" (13,460) and "Signs of Rodents" (8,403). "Conditions attracting rodents" was excluded from the Kernel Density Analysis.
Instant Insights: Critical locations by Borough, Neighborhood and Street:
Ranks 9 to 6 - Mott Haven, Melrose South: Willis Av, Courtland Avenue to Morris Av & East 144th St. to 152nd St. Most severe location in NYC
Ranks 8 to 6 - Crown Heights, Clinton Hill, Bedford: Bedford Av. with Fulton St.
Rank 7 - Central Harlem South, Morningside Heights, Upper West Side: Malcolm X Boulevard to Amsterdam Av & 100th to 120th St.
Rank 7 – Yorkville. 1st to 2nd Av & East 82nd St. to east 89th St.
Rank 6 – East Harlem South, East Harlem North: Park Avenue to 2nd Av. & East 109th to 117th St.
Rank 6 - East Village: 1st Avenue to Av C & 10th St. to 20th St.
Rank 6 - Hamilton Heights.
How close are rats from possible food and shelter locations (urban features)?
Rat basic needs comprise food and shelter. The distance analysis is based on the relative distance between all reported Rat sightings and "target" locations, such as (public) Residential buildings, Food-related businesses, Open spaces and Parks, Parking lots, Education and Health-related buildings, the Subway system, heavy Commercial areas (business districts)
Table: Distance analysis between a reported rat (49.727 total) and a closest Urban Feature. The calculation is made for each urban feature at the time and it only accounts the closest feature from each rat point, followed by a rat count per distance band from each feature. These values reflect NYC as a whole. <0, 50, 100, 150, 200 meters>
Rats can best be found in large quantities near: Food-related Businesses (66% within 330ft distance), Parks & Recreation areas, in NYC Business Districts (36%) Parking Lots (35%) and Open spaces (24%).
Investigate the association between high Rodent density and NYC Land Uses
An analysis was conducted to determine the relationship between higher and lower rat complaints and the 11 Land Use classes as well as building characteristics, provided by the NYC PLUTO* database.
Rodent Density vs. NYC Land Uses < click on the image to enlarge >
The Rodent Density map (ranked by severity, from 9 Very-high to 2 Lower complaint density) was intersected with the NYC PLUTO 11 Land Uses <by tax lot> to obtain the respective areas (%). ALL NYC AREA. *PLUTO - Primary Land Use Tax Lot Output 17v1.1
Rodent Density rank 9 - 8 > See Map Here
Areas defined by a higher number of buildings with a heavy human use: Office & Commercial, Public Facilities & Institutions, and buildings with both Residential and Commercial use. All of these building have a high human use, and possibly more waste is generated around these locations. The number of buildings exclusively residential is below the NYC average and there is a higher proportion of parking lots and vacant land (8-9% combined).
The density of Buildings with residential and commercial use (0.11-0.15), are older (built years 1719-1982 in average) and have the minimum land assessed tax value.
In less severe areas <rank 7-5> Residential buildings compose most of the urban landscape, around 60% (multi-family walk-ups and with elevator, buildings with both residential and commercial use, and 1-2 family buildings). There is a significant number of Public Facilities and Institutions, ~12%.
These areas have higher residential-commercial building densities, with more floors, built in the early 1800's
In lower Rodent density areas <rank 4-2> There is less urban pressure with lower population and housing density. There is a larger proportion of 1-2 Family buildings and less Multi-family buildings with Elevator. There are more lots dedicated to Transport, Utility, Industrial and Manufacturing and a larger area dedicated to Open Space and Outdoor Recreation.
Very high Rodent densities may not always be a direct consequence of high population and housing units densities.
In the most notorious location for high Rat outspread - the southeastern Bronx, has fewer buildings with residential and commercial use, are older and have the lowest assessed tax value when compared to the rest of NYC.
Rodent reporting is limited to action. It is unknown if the same rodent is reported more than once, and not all rodent sighting is reported. It may not hold 100% of the times, but having an analytic-derived holistic view of any problem allows a better understanding of it.
- The Norway or brown rat -Rattus norvegicus is a pest of Asian origin that accepts human beings as a part of its environment.
- Brown rats are responsible for an estimated $19 billion of damage annually.
- In optimal conditions, a population of 2 can grow up to 15 000 in only one year, and they tend to breed until they have maxed out their food supply.
- The brown rat is nocturnal and has excellent swimming, climbing and digging skills.
- It prefers to live in burrow systems, drains, sewers and buildings.
- Rats have a 1-year lifespan and a foraging range of 150 feet (40-50 meters).
- They are omnivorous and need approx 1 ounce (20-30 gr.) per day of human food and feedstock.
- The Norway rat varies in color and size, depending on how old it is and where it lives. As a result, people call it different names (city rat, brown rat, sewer rat, wharf rat, river rat, alley rat, house rat), but it’s all one species.
- Some juvenile rats are mistaken by mice. It is known that rats prey mice so it is unlikely for these species to share the same territory.
In “Rats in Urban America” from James Clinton (1969), it can be read: In cities, rat-inflicted injuries are most common (a) under crowded conditions, (b) in substandard housing, (c) in areas with poor environmental sanitation, or (d) in neighborhoods where rat-infested property is being controlled.
Besides exacting a heavy economic toll through property and infrastructure damage, waste and contamination, the rat is a serious health hazard. Leptospirosis, a worldwide zoonosis, is commonly found in rats.
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Preventing Rats on Your Property - A Guide for Property Owners and Tenants. NYC DHMH
ON THE NEWS: On July 12 2017, Mayor Bill de Blasio announced a $32 million, multi-agency plan to reduce the city’s rat population that targets the three most infested parts of city. “This investment is a multi-pronged attack to dramatically reduce the rat population in the City’s most infested areas and improve the quality of life for residents. (…) All New Yorkers deserve to live in clean and healthy neighborhoods.”
Vanessa Mateus, Geospatial Analyst
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