Caspian Tern

White ring with a black three alpha-numeric code, starting letter "V".

note 1 : project started in 2023.

note 2 : used codes are : V00-V99.

note 3 :

Yellow ring with a black three alpha-numeric code.

note 1 : in 2022 used codes are : Wxx, Xxx, Yxx and Zxx into use as well as also alpha-numeric rings starting with letters C and F (A is already in use in another project and letters not used are : B, D and E.
In 2025 theseletters are used : J, K, L, U, V.

used combinations are : 
C / letter / number
C / number / letter
C / number / number
F / letter / number
F / number / letter
F / number / number

note 2 : y = yellow ; x = letter ; n = number.
y- Jxn, y- Jnx, y- Jnn,  y- Kxn, y- Knx, y- Knn, y- Lxn, y- Lnx, y- Lnn, y- Uxn, y- Unx, y- Unn,  y- Vxn, y- Vnx, y- Vnn.

note 3 : 

White ring with a black three alpha-numeric code, starting letter "X".

note 1 : used codes are : X00-X99, XA0-XZ9 and X0A-X9Z.

note 2 :

Red ring with a white four alpha-numeric code (on one leg) and metal ring (on other leg).

note 1 : first letters are : A, C, F, H, J, K, L, M, N, R, T, U, Y.

note 2 : 

Red ring with white a 3 alpha-numeric code.

note 1 : first letters are : A, C, F, H, J, K, L, M, N, R, T, U, Y.

note 2 : 

Yellow ring with a black three alpha-numeric code (letter/number/letter).

note 1 : birds ringed by the Birdlife Alcyon project on the Ile aux Oiseaux in the Sine-Saloum National Park in Senegal.

note 2 :

Yellow ring with a black three alpha code.

note 1 : used codes are Cxx, Fxx, Jxx, Kxx, Lxx, Uxx and Vxx. and for the year 2015-2020 : Mxx, Nxx, Uxx, Pxx, Sxx, Txx.

note 2 : up to 2014, a total of 730 rings were delivered since 2008-2014.

note 3 :  in 2022 we have planned to take also codes Wxx, Xxx, Yxx and Zxx into use as well as also alpha-numeric rings starting with letters C and F (A is already in use in another project and letters not used are : B, D and E.
Also combinations of numbers/letters in all possible orders, i.e. "C/letter/number", "C/number/letter", "C/number/number"  & the same for F.
See project : https://cr-birding.org/node/6042

note 4 :

Combination of a c-ring and a coded c-ring.

note 1 : a partnership between Oregon State University, Real Time Research,
and the USGS - Oregon Cooperative Fish and Wildlife Research Unit.

Combination of c-rings (on both tarsi).

note 1 : a partnership between Oregon State University, Real Time Research,
and the USGS - Oregon Cooperative Fish and Wildlife Research Unit.

c-ring and metal ring.

note 1 :