Migratory and breeding behaviour of Water Rails Rallus aquaticus in east-central Scotland revealed by geolocators

README: Data for "Migratory and breeding behaviour of Water Rails Rallus aquaticus in east-central Scotland revealed by geolocators"

Associated journal article can be found here: https://doi.org/10.1080/00063657.2026.2641735   Primary contact for this repository: Robert Patchett; University of St Andrews, Scotland; [email protected]   1. Project OverviewThis document accompanies the manuscript titled: "Migratory and breeding behaviour of Water Rails Rallus aquaticus in east-central Scotland revealed by geolocators" 

Abstract: CapsuleThe Water Rail breeding population at the Tay Reedbeds, Scotland, is partially migratory.AimsTo investigate the migratory and breeding behaviour of Water Rails in the Tay Reedbeds. MethodsLight-level geolocators were used to estimate migration timing, identify non-breeding locations, and infer breeding behaviour.ResultsFive breeding birds remained resident year-round, two migrated to Ireland for the winter (including one individual tagged in two years that migrated in both), and two additional birds arrived from northeast Europe to winter in the Tay Reedbeds. Based on incubation periods ≥19 days as an indicator of success, 10 of 15 incubation attempts (67%) were successful. Among the 10 bird-years (n = 9 individuals, with one bird monitored across two years), 50 % were single-brooded, 10 % double-brooded, 20 % made a second attempt after failure, 10 % made two failed attempts before a successful one, and 10 % made a single unsuccessful attempt.ConclusionThe breeding population of Water Rail in Britain, previously considered resident, is partially migratory. Light-level geolocators can provide valuable insights into breeding ecology, particularly for species where direct observation is challenging.

Geolocator data used in this study can be found in the Movebank Data Repository here: https://doi.org/10.5441/001/1.735

2. Contents* README.txt - This file* migration_data.csv - Data on Water Rail migration timing and locations derived from light-level geolocation data * incubation_periods.csv - Data on Water Rail incubation derived from light-level geolocation data