| Coordinators:Albert de Jong
 Leon Kelder
 Roland-Jan Buijs
 Thijs Horst
 Merijn Loeve
 Mars Muusse
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 | Caspian Gull cachinnans  A:Y 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 Y-A:Y and metal 5.632.645, ringed as  pullus Larus cachinnans on  May 16 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. Loeve
 Data for nest NB - 2025. 
        
        
        
        
        
        
        
        
        
        
        
        
          | Metal    ring | Colour ring | Date | Species | Age | Clutch size | Location | Nest code | Ringer | Head+Bill | Mass | Wing | Parents |  
          | NLA 5632644 | y-A:X | 16-5-2025 | Caspian Gull | pullus | 2 eggs | the Netherlands, De Kreupel - eiland N. | NB | Leon Kelder | 53,2 | 88,0 |  |  |  
          | NLA 5632645 | y-A:Y | 16-5-2025 | Caspian Gull | pullus | 2 eggs | the Netherlands, De Kreupel - eiland N. | NB | Leon Kelder | 49,2 | 69,0 |  |  |    |