| Coordinators:Albert de Jong
 Leon Kelder
 Roland-Jan Buijs
 Thijs Horst
 Merijn Loeve
 Mars Muusse
 Home Project InfoInternational trend
 National trend
 Site characteristics
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 Future
 | Caspian Gull cachinnans  A:J 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 R4 - 2025. 
        
        
        
        
        
        
        
        
        
        
        
        
          | Metal    ring | Colour ring | Date | Species | Age | Clutch size | Location | Nest code | Ringer | Head+Bill | Mass | Wing | Parents |  
          | NLA 5632633 | y-A:K | 16-5-2025 | Caspian Gull | pullus | 2 eggs | the Netherlands, De Kreupel - eiland R. | R4 | Leon Kelder | 62,7 | 159,0 |  |  |  
          | NLA 5632634 | y-A:J | 16-5-2025 | Caspian Gull | pullus | 2 eggs | the Netherlands, De Kreupel - eiland R. | R4 | Leon Kelder | 56,1 | 111,0 |  |  |    |