Low cost audiovisual playback and recording triggered by radio frequency identification using Raspberry Pi

PeerJ. 2015 Apr 7:3:e877. doi: 10.7717/peerj.877. eCollection 2015.

Abstract

Playbacks of visual or audio stimuli to wild animals is a widely used experimental tool in behavioral ecology. In many cases, however, playback experiments are constrained by observer limitations such as the time observers can be present, or the accuracy of observation. These problems are particularly apparent when playbacks are triggered by specific events, such as performing a specific behavior, or are targeted to specific individuals. We developed a low-cost automated playback/recording system, using two field-deployable devices: radio-frequency identification (RFID) readers and Raspberry Pi micro-computers. This system detects a specific passive integrated transponder (PIT) tag attached to an individual, and subsequently plays back the stimuli, or records audio or visual information. To demonstrate the utility of this system and to test one of its possible applications, we tagged female and male tree swallows (Tachycineta bicolor) from two box-nesting populations with PIT tags and carried out playbacks of nestling begging calls every time focal females entered the nestbox over a six-hour period. We show that the RFID-Raspberry Pi system presents a versatile, low-cost, field-deployable system that can be adapted for many audio and visual playback purposes. In addition, the set-up does not require programming knowledge, and it easily customized to many other applications, depending on the research questions. Here, we discuss the possible applications and limitations of the system. The low cost and the small learning curve of the RFID-Raspberry Pi system provides a powerful new tool to field biologists.

Keywords: Animal communication; Automated playback; Event logging; Parental care; RFID; RPi; Raspberry Pi; Tree swallow.

Grants and funding

Funding was provided by a U.S. National Science Foundation (NSF) grant (Frances Bonier, Ignacio T. Moore, and Mark F. Haussmann; IOS-1145625), the Natural Sciences and Engineering Research Council of Canada, and a Banting Postdoctoral Fellowship (FB). During the preparation of the manuscript, Ádám Z. Lendvai was supported by a Hungarian Scientific Research Fund (OTKA K113108). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.