🐀 rats@basis.ai FAQ 🐀

We are studying the behaviors of urban rats in collaboration with urban municipalities and other integrated pest management practitioners.

What is Basis Research Institute?

Basis is a non-profit research organization focused on understanding mathematical principles of complex intelligent systems, including the social behaviors of animals. Our work is part of a broader effort to understand the social dynamics of wild rats in complex, natural environments. You can learn more about Basis here.

Why are we collecting audio recordings of urban rats?

Rats are among the most abundant non-human urban animals worldwide, and their populations are growing. Rats are also highly intelligent, highly social creatures whose behaviors have not been extensively studied in their natural habitat: cities. We hope that by discovering how wild rats behave and use urban environments, we can better understand their complex social lives, and in doing so develop effective and humane rat population management strategies.

What do rats sound like?

Rats are nocturnal animals that, like birds during the day, vocalize continuously through the night. Unlike birds, most rat vocalizations fall outside of the human hearing range, so we can’t hear them.

With the help of specialized ultrasonic microphones, however, we can listen in to the ‘silent’ ultrasonic world of wild rats. The videos below show what this reveals. On the top are rat vocalizations with audio in the human hearing range. Below are the same vocalizations, but pitch-shifted so you can hear the ultrasonic regime in which rats communicate. The dashed line marks the approximate human hearing limit (~20 kHz).

What data are we recording?

We are recording ultrasonic audio (at sampling rates of up to 384 kHz) using devices that record at night when rats are active. All recording sites are clearly marked by signs indicating that a recording is taking place. Our devices are designed to detect rat ultrasonic vocalizations, but they may also detect incidental human speech. Because we are only interested in rat vocalizations, we have developed a custom redaction pipeline to automatically remove intelligible human speech signals from our data (see below for more detail and an example). You can read our formal data use policy here.

What will we do with our data?

We use our data to study the role of vocal communication in the social lives of urban rats. Our research will help cities and pest management partners better manage urban rat populations, while helping us (and you!) better understand the complex social lives of these fascinating creatures. Questions we hope to answer include: How do rats use acoustic information to make social decisions? Do individual rats have vocal signatures? Do social groups from different locations, cities, or parts of the world communicate with different dialects?

Are our sensors capable of recording human speech?

Yes: our sensors may record human speech, but we are only interested in what rats are saying, not humans. That means that we are not analyzing the contents of human speech detected by our microphones, and all identifiable human signals in audio we record will be redacted from our data and permanently deleted. During the redaction process, we may retain timestamps (start and stop times) of automatically detected speech as a readout of human activity near rats. However, the content of these speech intervals will be removed prior to any analyses, and the purpose of these analyses will be only to better understand how human presence alters rat behavior.

What steps is Basis taking to respect the privacy of city residents?

Basis has developed a comprehensive privacy policy and protocol, modeled after the City of Boston Ordinance on Surveillance Oversight and Information Sharing. You can read it here. Our protocol is designed to prioritize privacy at each stage of data collection and analysis. First, data are collected on encrypted devices and transmitted to secure servers accessible only to trained Basis personnel. Once collected, human signals in the data are redacted via an automated pipeline, with validation by trained Basis personnel. We developed a custom redaction procedure because we care about privacy, and we are not aware of off-the-shelf methods to automatically redact human signals from audio data at scale. You can contact us at rats@basis.ai if you are interested in applying our redaction pipeline to your own data.

You can listen to an example audio clip before and after our redaction process below. Signal above the dashed line (the human hearing limit) is from a vocalizing rat; vocalizing humans are Basis researchers:

I would like a recording device to be removed - what should I do?

Who is funding this research?

Our team’s research is funded by a combination of public and private sources, including the Wild Animal Initiative, anonymous philanthropic donations, and the National Institutes of Health. If you are interested in supporting this work, please contact rats@basis.ai, or donate to Basis through the Donate button at the bottom of the website.

Where can I find out more?

You can read an example of our previous research here, as well as popular-press articles about it here, here, and here. You can also find more information about the team conducting the research here.

Who should I contact with questions or concerns?

You can contact us at rats@basis.ai.