In March 2020, New York declared a state of emergency in response to a global pandemic. But despite social distancing and lockdown orders, CBS News New York’s recent analysis of 311 data showcased a 22% jump in rodent-related complaints from 2019 to 2021.

Rodents continue to pose a major threat to public health, sanitation, and the wellbeing of people in New York City. But during COVID-19 when people’s lives were at stake, what did the rodent complaints data look like? Using the NYC 311 Data, this project explores how rodent complaints have varied across different neighborhoods in New York City from 2019 to 2021.

Research Questions

In order to evaluate how rodent complaints have varied across different neighborhoods in New York City from 2019 to 2021, I asked the following questions to guide my visualizations:

1. How has the number of rodent complaints changed over time?
2. Where were the complaints being filed from?
3. What type of complaints were being filed?
4. What type of locations were the complaints being filed for?

Through this project, I intend to benefit all NYC residents, especially those residing in high complaint rate areas, as well as city pest control services and communities. My goal is to create visualizations that help my audience make sense of the data surrounding rodent-related reports filed during COVID-19. And most importantly, I hope that my analysis can provide better insight on areas that may require increased attention from pest control efforts, educate residents about areas and seasons with higher complaint rates, and suggest improvements on urban sanitation policies.

1. How has the number of rodent complaints changed over time?

The first chart is a bar graph showcasing the total number of rodent complaints filed per year from 2019 to 2021. I thought creating this visualization made an interesting start to the analysis because it indicates 2020 as the year with the least number of complaints. Though it’s still soon to tell, I thought this potentially meant that less complaints were filed due to less in-person activity during COVID-19.

Furthermore, what makes this visualization more intriguing is that 2021 had the most complaints filed among all three years, despite seeing a drop in complaints during the previous year of 2020.

The next chart is a combined bar and line graph breaking down the total number of rodent complaints filed by month from 2019 to 2021. The yearly bar colors remained the same as that of the previous chart, with 2019 months marked in pink, 2020 months marked in green, and 2021 months marked in purple. This allows readers to quickly distinguish which bars represent data from a specific year. Throughout the three years, the warmer months consistently had more complaints than the colder months.

Circling back to my initial assumption about the pandemic, this monthly breakdown suggests that COVID-19 may have had some effect on the number of rodent complaints filed. For example, March 2020 shows a decrease in rodent complaints, with numbers in April 2020 falling even more. At the same time, March 2020 was when the state of emergency was declared, while pandemic protocols were becoming solidified in April 2020.

Something else that caught my eye about this visualization was the spike in complaints during October 2021. While I didn’t have the exact answers as to what could’ve caused this surge, it made me think about the possibilities: sudden increase in human activity, amount of trash, weather conditions, more businesses open, etc.

2. Where were the complaints being filed from?

The following map above is a density map showcasing the number of complaints by zip code and borough. The bottom layer of the map color codes the five NYC boroughs to easily distinguish the neighborhoods. The top layer of the map is covered with a variety of mouse icons. The bigger icons indicate a higher number of reports in the corresponding zip code and vice versa.

The map indicates that Brooklyn filed the most complaints throughout the three years. However, it is important to consider how these complaints happened. After observing high complaints in certain zip codes, it makes me wonder whether these complaints are distinct and filed at different addresses or if the complaints are repetitious regarding the same locations.

We already know that Brooklyn filed the most rodent complaints from the previous map. But to get a better feel for how monthly complaints varied by borough, I created a stacked line graph displaying a timeline of monthly complaints filed per borough. I think this graph is especially helpful with identifying peak months for each borough, as they slightly vary from each other. It turns out that Brooklyn’s peak months of May 2019, July 2020, and June 2021 were not the same as the peak months for total complaints filed by all boroughs. For reference, the peak months of each year combining data from all boroughs were August 2019, August 2020, and July 2021.

3. What type of complaints were being filed?

The chart above is a tree map I created using the Borough, Descriptor, and count of complaints variables. The colors of the map represent each NYC borough, while the size and spread of each borough mark depends on the total number of complaints. Then, with the descriptor variable, I was able to break down the heat map further so that the number of complaints in each borough is visualized by complaint type.

There are five complaint types that can be reported through 311: rat sighting, mouse sighting, condition attracting rodents, signs of rodents, and rodent bite. In all five boroughs, people filed the most complaints for rat sighting. The least filed complaint type was rodent bite, as none of the boroughs reported more than ten complaints. Hence, the rodent bite data cannot be seen without the mouse hovering over the map, no pun intended.

Once again, this map makes me wonder how people filed these complaints. How often did people create reports for rat sightings? What was considered a condition attracting rodents? Were there any other potential skewing factors?

4. What type of locations were the complaints being filed for?

In this final chart, the stacked bar graph presents the total number of complaints by complaint type, with each “stack” representing a location type that reports were filed for. The given data indicates that majority of complaints were filed for residential location types. The residential locations include apartment buildings, private residencies, as well as family mixed use buildings.

I ended up creating a Location Type (group) variable for the stacked bar graph to narrow down the location types into four different categories. Since the original data set listed over fifty different location types, it was initially a challenge to visualize a legible graph. Although I tried my best to be as objective as possible, I realize the potential biases that arise from how I choose to define and group data into broader categories.

About the Data

Since the list of 311 service requests covers a variety of complaints from 2010 to present, I queried the data with key word “Rodent” input into the Complaint Types filter so that the data set contains only rodent-related complaints. I was also interested in evaluating data from 2019 to 2021 to observe any patterns and changes that occurred before, during, and after COVID-19. Therefore, I filtered the Created Date column to showcase complaints from January 1st, 2019, 12:00:00 AM to December 31st, 2021, 11:59:59 PM. While no further querying was done to the data set, other variables, such as Location Type, were adjusted in the Tableau sheets.

The most common variable I used was the number of filed complaints, as all six visualizations relied on this data. Some other variables that played an important role in the visualizations include Descriptor (i.e. Rat Sighting), Location Type (i.e. Commercial), and Borough (i.e. Brooklyn). Since my primary focus was to analyze the changes in complaints across different NYC neighborhoods from 2019 to 2021, I filtered out any data listed as null, unknown, or other values in the Borough column.

Next Steps

Overall, the exploration of 311 complaints has helped me recognize some common patterns behind the “when” and “where” of these rodent-related reports filed from 2019 to 2021. Specifically, I believe that the findings of this analysis call for extra pest control initiatives in higher complaint areas like Brooklyn and more attention to complaint rates during warmer seasons.

If I were to take this project a step further, I would like to learn more about the “who” and “why” of these complaints in order to gain deeper meaning of the stories being told by this 311 data set. I would analyze additional variables, such as Resolution Descriptions or Incident Address, to further investigate people’s complaint-filing habits on rodent issues. I would also observe data from a broader period of time to identify more common and consistent patterns throughout longer time frames. I think working with another 311 complaint, like trash-related complaints, to spot any relationships between that and rodent complaints could also add valuable information as to why these rodent complaints might happen.