How to quantify animal activity from radio‐frequency identification (RFID) recordings

Abstract

Automated animal monitoring via radio‐frequency identification (RFID) technology allows efficient and extensive data sampling of individual activity levels and is therefore commonly used for ecological research. However, processing RFID data is still a largely unresolved problem, which potentially leads to inaccurate estimates for behavioral activity. One of the major challenges during data processing is to isolate independent behavioral actions from a set of superfluous, nonindependent detections. As a case study, individual blue tits (Cyanistes caeruleus) were simultaneously monitored during reproduction with both video recordings and RFID technology. We demonstrated how RFID data can be processed based on the time spent in‐ and outside a nest box. We then validated the number and timing of nest visits obtained from the processed RFID dataset by calibration against video recordings. The video observations revealed a limited overlap between the time spent in‐ and outside the nest box, with the least overlap at 23 s for both sexes. We then isolated exact arrival times from redundant RFID registrations by erasing all successive registrations within 23 s after the preceding registration. After aligning the processed RFID data with the corresponding video recordings, we observed a high accuracy in three behavioral estimates of parental care (individual nest visit rates, within‐pair alternation and synchronization of nest visits). We provide a clear guideline for future studies that aim to implement RFID technology in their research. We argue that our suggested RFID data processing procedure improves the precision of behavioral estimates, despite some inevitable drawbacks inherent to the technology. Our method is useful, not only for other cavity breeding birds, but for a wide range of (in)vertebrate species that are large enough to be fitted with a tag and that regularly pass near or through a fixed antenna.

Enduring rules of care within pairs - how blue tit parents resume provisioning behaviour after experimental disturbance

“…A full description of the RFID hardware, analytical procedure and data validation is detailed in Iserbyt et al . 34 . In short, exact arrival times were isolated from successive redundant RFID registrations, by sorting all registrations per ID and erasing each registration within 23 seconds after the preceding registration 34 .…”

“…34 . In short, exact arrival times were isolated from successive redundant RFID registrations, by sorting all registrations per ID and erasing each registration within 23 seconds after the preceding registration 34 . Based on these trimmed readings we calculated individual behavioural activity as the number of nest arrivals for each hour (i.e.…”

Handicapping Males Does Not Affect Their Rate of Parental Provisioning, but Impinges on Their Partners' Turn Taking Behavior

“…Thus, parents take turns by adjusting their visit rates in response to each other, which may ultimately be reflected in a high proportion of alternated feeding visits within pairs. Such coordinated feeding visits have been found in a number of observational studies (Johnstone et al, 2014;Bebbington and Hatchwell, 2016;Koenig and Walters, 2016;Iserbyt et al, 2017Iserbyt et al, , 2018Savage et al, 2017;Leniowski and Wegrzyn, 2018;Wojczulanis-Jakubas et al, 2018), but the number of studies testing the significance of conditional cooperation for conflict resolution remains limited (but see Griffioen et al, 2019;Iserbyt et al, 2019). Experiments are vital for our understanding of conditional cooperation given the analytical difficulties faced in observational studies that may prevent to prove whether parents actively take turns (Schlicht et al, 2016;Ihle et al, 2019;Santema et al, 2019).…”

Experimental facilitation of heat loss affects work rate and innate immune function in a breeding passerine bird

“…Thus, a new recording of T s could only be obtained after 60 s from the initial reading (if the bird was still within reading range, the next reading usually occurred after 60-62 s). This way of recording feeding visits could create two potential sources of error (see Iserbyt et al, 2018):…”