| Coordinators:Albert de Jong
 Leon Kelder
 Roland-Jan Buijs
 Thijs Horst
 Merijn Loeve
 Mars Muusse
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 | Caspian Gull cachinnans  S|F 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 G-S|F and metal Arnhem NLA 5.639.071, ringed as  pullus Larus  cachinnans on May 09 2025 at IJsselmeer (De Kreupel), Holland (5247.00 N 513.00 E), 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 C12 - 2025. 
        
        
        
        
        
        
        
        
        
        
        
        
          | Metal    ring | Colour ring | Date | Species | Age | Clutch size | Location | Nest code | Ringer | Head+Bill | Mass | Wing | Parents |  
          | NLA 5639069 | g-S|D | 09-5-2025 | Caspian Gull | pullus | 3 eggs | the Netherlands, De Kreupel - eiland C. | C12 | Leon Kelder | 65,2 | 199,0 |  |  |  
          | NLA 5639070 | g-S|E | 09-5-2025 | Caspian Gull | pullus | 3 eggs | the Netherlands, De Kreupel - eiland C. | C12 | Leon Kelder | 64,2 | 183,0 |  |  |  
          | NLA 5639071 | g-S|F | 09-5-2025 | Caspian Gull | pullus | 3 eggs | the Netherlands, De Kreupel - eiland C. | C12 | Leon Kelder | 59,5 | 140,0 |  |  |    |