| Coordinators:Albert de Jong
 Leon Kelder
 Roland-Jan Buijs
 Thijs Horst
 Merijn Loeve
 Mars Muusse
 Home Project InfoInternational trend
 National trend
 Site characteristics
 Breeding biology
 Fecundity
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 Future
 | Caspian Gull cachinnans  C:4 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 D10 - 2025. 
        
        
        
        
        
        
        
        
        
        
        
        
          | Metal    ring | Colour ring | Date | Species | Age | Clutch size | Location | Nest code | Ringer | Head+Bill | Mass | Wing | Parents |  
          | NLA 5633739 | y-C:3 | 16-5-2025 | Caspian Gull | pullus | 2 eggs | the Netherlands, De Kreupel - eiland D. | D10 | Leon Kelder | 52,6 | 104,0 |  |  |  
          | NLA 5633740 | y-C:4 | 16-5-2025 | Caspian Gull | pullus | 2 eggs | the Netherlands, De Kreupel - eiland D. | D10 | Leon Kelder | 52,9 | 85,0 |  |  |  |