RT Journal Article
T1 Factors affecting detection probability: Insights from banding data in a long-term continent-wide monitoring program
A1 Gicquel, Morgane
A1 Alonso, Juan C.
A1 Nilsson, Lovisa
A1 Low, Matthew
A1 Alonso López, Javier Antonio
A1 Alonso, Javier A.
A1 Boiko, Dmitrijs
A1 Bridge, Damon
A1 Dulau, Patrick
A1 Heinicke, Thomas
A1 Kettner, Anne
A1 Kiat, Yosef
A1 Kurlavičius, Petras
A1 Lundgren, Sigvard
A1 Modrow, Michael
A1 Nowald, Günter
A1 Ojaste, Ivar
A1 Salvi, Alain
A1 Sandvik, Jostein
A1 Ticháčková, Markéta
A1 Torrijo, Antonio
A1 Valkama, Jari
A1 Végvári, Zsolt
A1 Månsson, Johan
AB Bird banding studies are essential for providing critical data on species population demographics and movements, as important components for understanding their ecology and conservation and management applications. However, analysing sightings of banded individuals is often complicated by untested assumptions of the species’ behaviour or visibility of the bands, leading to biased populations estimates, especially in large-scale long-term studies. In this study we investigate factors influencing detection rates of colour-banded Eurasian cranes (Grus grus), from a monitoring program spanning 35 years, involving 5049 marked individuals using four different types of bands (ELSA, ‘Finnish’, ‘Spanish’ and alphanumeric) with 172,725 resightings along migratory flyways. Data were compiled from European national banding schemes and the internet-based Crane Observation Ring Archive (iCORA). We used capture-mark-recapture mixture models to study the variation in detection probability from differences in the type of bands used, time since marking, year of observation, natal origin and an additional parameter to account for unexplained resighting heterogeneity. All band types showed high detection probabilities in their first years (as high as 80 %) but declined significantly over time, with detection rates halving within 20 years. Although starting with the lowest detection probability, alphanumeric bands remained relatively stable over time. There was a general increase in detection probability over the 35-year study period, which can be attributed to enhanced observation efforts, addition of pictures to reports and improved coordination of reports. Detection also varied by natal country, each population’s migratory routes, which were related to differences in monitoring efforts and habitat conditions along the flyways. Our findings emphasize the importance of band type, observation effort, migration pattern and environmental factors in determining detection probabilities, but also the importance to account for unexplained heterogeneity with a mixture model. This study is crucial for the study of demographic parameters within the European crane population and future evidence-based population management.
PB Elsevier
SN 1470-160X
YR 2025
FD 2025-09
LK https://hdl.handle.net/20.500.14352/125348
UL https://hdl.handle.net/20.500.14352/125348
LA eng
NO Gicquel, M., Alonso, J. C., Nilsson, L., Low, M., Alonso, J. A., Boiko, D., Bridge, D., Dulau, P., Heinicke, T., Kettner, A., Kiat, Y., Kurlavičius, P., Lundgren, S., Modrow, M., Nowald, G., Ojaste, I., Salvi, A., Sandvik, J., Ticháčková, M., … Månsson, J. (2025). Factors affecting detection probability: Insights from banding data in a long-term continent-wide monitoring program. Ecological Indicators, 178, 114020. https://doi.org/10.1016/j.ecolind.2025.114020
NO In Estonia, the crane banding efforts were additionally supported by the Research and Development Projects of the Estonian University of Life Sciences, under the project PM170161PKMH titled “Exploring the Common Crane (Grus grus) Migration Network Using Satellite Tracking to Develop a Novel Theory of Bird Migration”. In Spain, funds for marking and resighting cranes were provided by projects PB87-0389 and PB91-0081 of the Spanish Ministry of Education and Science,We thank the Carl Tryggers Foundation and the Swedish Environmental Protection Agency for their financial support towards the post-doctoral fellowship of Morgane Gicquel
NO Estonian University of Life Sciences
NO Ministerio de Educación y Ciencia (España)
NO Carl Tryggers Foundation
NO The Swedish Environmental Protection Agency
DS Docta Complutense
RD 24 dic 2025