This video is about Eurasian coots in Sweden.
From Ringing & Migration, Volume 29, Issue 1, 2014:
Rallidae are common and widespread, yet relatively poorly studied. We analysed the ringing data from more than 8,000 Common Coot Fulica atra, accumulated between 1950 and 1982 in Camargue, southern France, in terms of the dynamics of their biometrics throughout the year, migratory pathways and annual survival rate. Mean monthly body mass and wing length indicate seasonal differences, with birds captured in autumn and winter being heavier and larger than those captured in spring and summer.
The temporal and spatial distribution across Europe of more than 950 ring recoveries indicates a mixing of sedentary and migratory birds. Capture–recapture analysis indicated lower annual survival rates during the year after ringing, and greater survival rates in adults and in males. Mean survival rate across sex and age classes greater than one year after ringing was 55%. This is somewhat lower than found by other studies, and may be influenced by Coot hunting in the Camargue, especially during the years of this study.