| 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  S|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 |  Data for nest D4 - 2025. 
        
        
        
        
        
        
        
        
        
        
        
        
          | Metal    ring | Colour ring | Date | Species | Age | Clutch size | Location | Nest code | Ringer | Head+Bill | Mass | Wing | Parents |  
          | NLA 5639085 | g-S|X | 09-5-2025 | Caspian Gull | pullus | 2 eggs | the Netherlands, De Kreupel - eiland D. | D4 | Leon Kelder | 61,5 | 150,0 |  |  |  
          | NLA 5639086 | g-S|Y | 09-5-2025 | Caspian Gull | pullus | 2 eggs | the Netherlands, De Kreupel - eiland D. | D4 | Leon Kelder | 63,8 | 165,0 |  |  |  
          | NLA 5639086 | g-S|Y | 16-5-2025 | Caspian Gull | pullus | 3 eggs | the Netherlands, De Kreupel - eiland D. | D9 (?) | Leon Kelder |  |  |  |  |  
          | NLA 5639086 | g-S|Y | 30-5-2025 | Caspian Gull | pullus | -- | the Netherlands, De Kreupel - eiland D. | D4 | Leon Kelder |  |  |  |  |  
          | NLA 5639087 | g-S|Z | 09-5-2025 | Caspian Gull | pullus | 2 eggs | the Netherlands, De Kreupel - eiland D. | D4 | Leon Kelder | 54,4 | 100,0 |  |  |  
          | NLA 5639087 | g-S|Z | 16-5-2025 | Caspian Gull | pullus | -- | the Netherlands, De Kreupel - eiland D. | D4 | Leon Kelder |  |  |  |    |