| Coordinators:Albert de Jong
 Leon Kelder
 Roland-Jan Buijs
 Thijs Horst
 Merijn Loeve
 Mars Muusse
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 | Caspian Gull cachinnans  E|A 1CY, May 2025, colony De Kreupel, the Netherlands.
        
          | You can participate in this project too! 
            Please send in your observations of colour ringed birds to: ring@buijsecoconsult.nl |  Tibia G-E|A and metal NLA 5.639.017, ringed as  pullus Larus cachinnans on May 02 2025 at IJsselmeer (De Kreupel), Noord-Holland, by ringer Leon Kelder. Recoveries:18-07-2025 IJsselmeer (De Kreupel), Noord-Holland, NL 5.247,00 N 513,00 E colourring read T. Horst & M. Muusse
 Data for nest H9 - 2025. 
        
        
        
        
        
        
        
        
        
        
        
        
          | Metal    ring | Colour ring | Date | Species | Age | Clutch size | Location | Nest code | Ringer | Head+Bill | Mass | Wing | Parents |  
          | NLA 5639015 | g-D|B | 02-5-2025 | Caspian Gull | pullus | 3 eggs | the Netherlands, De Kreupel - eiland L. | L1 | Leon Kelder | 50,8 | 78,0 |  |  |  
          | NLA 5639016 | g-D|J | 02-5-2025 | Caspian Gull | pullus | 3 eggs | the Netherlands, De Kreupel - eiland L. | L1 | Leon Kelder | 48,7 | 68,0 |  |  |  
          | NLA 5639017 | g-E|A | 02-5-2025 | Caspian Gull | pullus | 3 eggs | the Netherlands, De Kreupel - eiland L. | L1 | Leon Kelder | 51,2 | 70,0 |  |  |  Ring was used before, in 2024. Now re-used. |