| Coordinators:Albert de Jong
 Leon Kelder
 Roland-Jan Buijs
 Thijs Horst
 Merijn Loeve
 Mars Muusse
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 | Herring Gull argenteus  E:K 1CY, July 2025, colony De Kreupel, the Netherlands.
        
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            Please send in your observations of colour ringed birds to: ring@buijsecoconsult.nl |  Tibia  Y-E:K and metal Arnhem NLA 5.633.834, ringed as  pullus Larus  argentatus on May 30 2025 at IJsselmeer (De Kreupel), Holland (5247.00 N 513.00 E), by ringer Leon Kelder. Recoveries:04-07-2025 IJsselmeer (De Kreupel), Noord-Holland, NL 5.247,00 N 513,00 E captured by ringer Leon Kelder
 26-07-2025 IJsselmeer (De Kreupel), Noord-Holland, NL 5.247,00 N 513,00 E colourring read Thijs Horst
 Data for nest C9 - 2025. 
        
        
        
        
        
        
        
        
        
        
        
        
          | Metal    ring | Colour ring | Date | Species | Age | Clutch size | Location | Nest code | Ringer | Head+Bill | Mass | Wing | Parents |  
          | NLA 5633834 | y-E:K | 30-5-2025 | Caspian Gull | pullus | 3 eggs | the Netherlands, De Kreupel - eiland C. | C9 | Leon Kelder | 65,6 | 243,0 |  |  |  
          | NLA 5633834 | y-E:K | 04-7-2025 | Caspian Gull | pullus | -- | the Netherlands, De Kreupel - eiland C. | C9 | Leon Kelder | 118,0 | 1142,0 | 322,0 |  |  
          | NLA 5633834 | y-E:K | 04-7-2025 | Caspian Gull | pullus | -- | the Netherlands, De Kreupel - eiland D. | C9 | Leon Kelder | 118,7 | 1077,0 | 321,0 |  |  
          | NLA 5633835 | y-E:L | 30-5-2025 | Caspian Gull | pullus | 3 eggs | the Netherlands, De Kreupel - eiland C. | C9 | Leon Kelder | 66,4 | 266,0 |  |  |  
          | NLA 5633836 | y-E:M | 30-5-2025 | Caspian Gull | pullus | 3 eggs | the Netherlands, De Kreupel - eiland C. | C9 | Leon Kelder | 62,6 | 222,0 |  |  |  |