Monitoring Banded Birds in Brazilian Marshes

For one year (August 2012-August 2013), we monitored the banded birds. We visited each marsh on a monthly basis and walked predefined transects (1 m wide) at a speed of 0.01 km/h. The transects were set 35 m apart and ran parallel to each other across the full length of each marsh (4 trails 500 m long in Mogi, 3 trails 300 m long in Salesópolis and 4 trails 100 m long in São José dos Campos). We spent a total of 620 h in Mogi (103 days), 336 h in Salesópolis (56 days) and 108 h in São José (26 days) divided equally between months. Every three months we moved the trail by 10 m to either side, depending on the local land features, to avoid spatial bias in our data. We sampled a total of 16 transects in Mogi, 12 in Salesópolis and 16 in São José. When a banded individual was sighted, we identified it and noted its geographical coordinates using a hand-held Global Position System unit (Garmin GPSMAP 62s). The GPS location error was usually lower than 4 m. When we heard a bird vocalize, if less than 15 m away, we used playback to call the bird for identification. When using playback, we noted only the initial position of the bird on that day, to avoid problems with the influence of playback on its behaviour [34 (link)].