| Coordinators:Albert de Jong
 Leon Kelder
 Roland-Jan Buijs
 Thijs Horst
 Merijn Loeve
 Mars Muusse
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 | Caspian Gull cachinnans  C:S 1CY, July 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  Y-C:S and metal Arnhem NLA 5.633.763, ringed as  pullus Larus cachinnans on May 16 2025 at IJsselmeer (De Kreupel), Holland (5247.00 N 513.00 E), by ringer Leon Kelder. Recoveries:13-07-2025 IJsselmeer (De Kreupel), Noord-Holland, NL 5.247,00 N 513,00 E colourring read T. Horst, M. Muusse & N. Colpaert
 18-07-2025 IJsselmeer (De Kreupel), Noord-Holland, NL 5.247,00 N 513,00 E colourring read T. Horst & M. Loeve
 Data for nest K2 - 2025. 
        
        
        
        
        
        
        
        
        
        
        
        
          | Metal    ring | Colour ring | Date | Species | Age | Clutch size | Location | Nest code | Ringer | Head+Bill | Mass | Wing | Parents |  
          | NLA 5633762 | y-C:R | 16-5-2025 | Caspian Gull | pullus | 2 eggs | the Netherlands, De Kreupel - eiland K. | K2 | Leon Kelder | 70,0 | 248,0 |  |  |  
          | NLA 5633763 | y-C:S | 16-5-2025 | Caspian Gull | pullus | 2 eggs | the Netherlands, De Kreupel - eiland K. | K2 | Leon Kelder | 70,0 | 281,0 |  |  |  below: Caspian Gull cachinnans  C:S 1CY,  July 13 2025, colony De Kreupel, the Netherlands. Picture: Thijs Horst & Mars Muusse.
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