Table 6 Recommendations for future colour ringing studies of ring fitting, data collection and mark-recapture studies, based on some of the challenges we encountered during our data preparation, and from the findings of our analyses
From: Colour-ring wear and loss effects in citizen science mark-resighting studies
Topic | Recommendation |
|---|---|
(A) Ring fitting | 1. Do not use colour-rings with cracks/deformations |
2. Consider ring placement—tarsus rings may wear rapidly in oyster bed type habitats, but tibia rings may be covered by feathers | |
3. Always report the condition of each ring during recaptures | |
4. Always report when rings are replaced, and the reason | |
5. Standardise practices about whether individuals should receive a new ring combination, or to only replace the worn/lost ring | |
6. Proactively replace rings if signs of wear begin to show | |
7. Monitor differences in wear rates of ring colours and avoid using colours that wear quickly | |
8. Avoid colour-coding schemes whereby individuals with a lost or moved ring may be misclassified as another individual | |
(B) Data collection and study design | 1. Provide training to citizen scientists about how to report birds with worn or lost rings |
2. Provide several examples of differences between colour rings in good, slightly worn and heavily worn conditions, such as built-in examples of ring wear on an app or website that pop-up when a worn ring is reported | |
3. Create a compulsory data field in an online portal, which is automatically blank and hence requires the observer to select whether a ring is in good condition, worn or lost | |
4. Always report worn/lost rings, even when the code is not identifiable | |
5. Create an additional data field to note which leg has the worn/missing colour-ring or expand point (3) above to create a compulsory field for each ring | |
6. Create an additional field to report how the individual was identified (e.g. site fidelity, metal band, morphology) | |
7. Combine marking techniques, e.g. flags and rings, to estimate separate resighting parameters and accurately identify loss for each scheme | |
8. Catalogue how ring batches were manufactured, in particular the material used, ring thickness and engraving depth | |
(C) Mark-recapture analyses | 1. Citizen scientist observations may lead to more accurate estimates of ring wear/loss |
2. Determine whether observer behaviours, and reports of worn/lost rings, are more likely affecting resighting probabilities or survival estimates | |
3. Consider how habitat-specific patterns of ring wear/loss may impact multi-state models, in particular locale-specific estimates of survival and estimates of transitions (migration) | |
4. Consider creating a group to which individuals transition once rings are known to be lost |