Terns

Yellow ring with a black three alpha-numeric code.

note 1 : always letter 'N' or 'H' on the first position OR always letter 'N' on the 2nd or 3rd position (eg. 2NA or 2AN).

note 2 : the letter N is followed by one letter and one number (eg. NV2 or N2V).  
note 2a : the letter H is followed by one letter and one number (eg. HV2 or H2V), by two letters (eg. HVN or HNV) or by two numbers (eg. H42). 

note 3 : used letters are : A, C, F, H, K, L, N, P, R, S, T, V, X, Z. Used numbers are 1, 2, 3, 4, 5, 6, 7, 8, 9.

note 4 : these codes were used in 2017-2019 on both adult and juvenile birds during the breeding season in the southwest of the Netherlands.

note 4 : IMPORTANT NOTICE: about 75 double codes starting with N (and followed by a letter and a number) were issued in 2017 by another project (ref to other project). These only differ in the position of the CR on the bird: mostly right tarsus for the Polish project, mostly left tarsus for the Dutch project. Please when reading a yellow Common Tern CR with an N on the first position note on what leg the CR is positioned.

note 5 : these codes were used in 2017-2018 on both adult and juvenile birds during the breeding season in the southwest of the Netherlands.

note 6 : a joint project of the Research Institute for Nature and Forest (INBO), Bureau Waardenburg and Ringgroup Delta.

note 7 : we use colour-rings in order to gain information on habitat use, juvenile dispersal, age of return and recruitment to the breeding colonies in the southwest of The Netherlands or beyond.

note 8 :