| Coordinators:Albert de Jong
 Leon Kelder
 Roland-Jan Buijs
 Thijs Horst
 Merijn Loeve
 Mars Muusse
 Home Project InfoInternational trend
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 | Caspian Gull cachinnans  C:= 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 |  Data for nest C14 - 2025. 
        
        
        
        
        
        
        
        
        
        
        
        
          | Metal    ring | Colour ring | Date | Species | Age | Clutch size | Location | Nest code | Ringer | Head+Bill | Mass | Wing | Parents |  
          | NLA 5633731 | y-B:Z | 16-5-2025 | Caspian Gull | pullus | 3 eggs | the Netherlands, De Kreupel - eiland C. | C14 | Leon Kelder | 52,4 | 76,0 |  |  |  
          | NLA 5633731 | y-B:Z | 06-6-2025 | Caspian Gull | pullus | -- | the Netherlands, De Kreupel - eiland C. | C14 | Leon Kelder |  |  |  |  |  
          | NLA 5633732 | y-C:= | 16-5-2025 | Caspian Gull | pullus | 3 eggs | the Netherlands, De Kreupel - eiland C. | C14 | Leon Kelder | 47,9 | 58,0 |  |  |  
          | NLA 5633732 | y-C:= | 06-6-2025 | Caspian Gull | pullus | -- | the Netherlands, De Kreupel - eiland C. | C14 | Leon Kelder |  |  |  |  |  
          | NLA 5633733 | y-C:+ | 16-5-2025 | Caspian Gull | pullus | 3 eggs | the Netherlands, De Kreupel - eiland C. | C14 | Leon Kelder | 54,8 | 90,0 |  |  |  |