Assessing the type and frequency of band resighting errors for Razorbill Alca torda with implications for other wildlife studies

• Main Authors: Lavers, Jennifer L., Jones, Ian L.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Pacific Seabird Group 2008
• Subjects: QH301 Biology; Alca torda; Razorbill
• Online Access: https://research.library.mun.ca/568/; https://research.library.mun.ca/568/1/assessing_type_frequency.pdf; https://research.library.mun.ca/568/3/assessing_type_frequency.pdf; http://www.marineornithology.org/PDF/36_1/36_1_19-23.pdf

Visual markers are frequently used in wildlife studies to identify individual animals and to track their behaviour (including movement) and survival. These markers are useful because identification can be made without recapturing individuals, thus minimizing disturbance. However, studies have shown that errors associated with reading and recording markers adversely influence the estimation of population parameters. Using the example of triangular field-readable leg bands on Razorbill Alca torda, we developed a simple experimental protocol for quantifying band resighting error rates and identifying trends in digit misidentifications. The resighting error rate varied from 0.035 to 0.134 depending on observer distance and conditions under which the bands were read. Misidentification of the digits 3 and 5 accounted for more than 48% of all errors made. In our study, 94% of all misread bands corresponded to a valid entry in the banding data base (i.e. misread numbers coincidentally referred to other banded birds), probably because more than 12 000 Razorbills have been banded from one long sequence of band numbers between 1980 and 2007. We conclude that band reading error is a neglected phenomenon that has likely had profound effects on the accuracy of survival studies, and we provide suggestions for minimizing the frequency of such errors.