| Coordinators:Albert de Jong
 Leon Kelder
 Roland-Jan Buijs
 Thijs Horst
 Merijn Loeve
 Mars Muusse
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 | Caspian Gull cachinnans  V|W 1CY, May 2025, colony De Kreupel, the Netherlands.
        
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            Please send in your observations of colour ringed birds to: ring@buijsecoconsult.nl |  Tibia G-V|W and metal NLA 5.639.119 ringed as  pullus Larus cachinnans on May 09 2025 at IJsselmeer (De Kreupel), Holland, NL 5247.00 N 513.00 E, by ringer Leon Kelder. Recoveries:31-08-2025 Ter Heijde (Zandmotor), Zuid-Holland, NL 5.203,00 N 411,00 E colourring read Leo Snellink
 Data for nest M13 - 2025. 
        
        
        
        
        
        
        
        
        
        
        
        
          | Metal    ring | Colour ring | Date | Species | Age | Clutch size | Location | Nest code | Ringer | Head+Bill | Mass | Wing | Parents |  
          | NLA 5639117 | g-V|T | 09-5-2025 | Caspian Gull | pullus | 3 eggs | the Netherlands, De Kreupel - eiland M. | M13 | Leon Kelder | 57,3 | 121,0 |  |  |  
          | NLA 5639117 | g-V|T | 30-5-2025 | Caspian Gull | pullus | -- | the Netherlands, De Kreupel - eiland M. | M13 | Leon Kelder |  |  |  |  |  
          | NLA 5639118 | g-V|V | 09-5-2025 | Caspian Gull | pullus | 3 eggs | the Netherlands, De Kreupel - eiland M. | M13 | Leon Kelder | 60,3 | 141,0 |  |  |  
          | NLA 5639118 | g-V|V | 22-5-2025 | Caspian Gull | pullus | -- | the Netherlands, De Kreupel - eiland M. | M13 | Leon Kelder |  |  |  |  |  
          | NLA 5639119 | g-V|W | 09-5-2025 | Caspian Gull | pullus | 3 eggs | the Netherlands, De Kreupel - eiland M. | M13 | Leon Kelder | 62,4 | 140,0 |  |  |    |