| Coordinator: Albert de Jong
 Merijn Loeve
 Roland-Jan Buijs
 Thijs Horst
 Leon Kelder
 Mars Muusse
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 | Caspian Gull cachinnans 1.6 1CY, May 13 2022, De Kreupel, the Netherlands.
        
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            Please send in your observations of colour ringed birds to: ring@buijsecoconsult.nl |  Red tibia ring  R-16 and metal ring Arnhem NLA 5.623.529, ringed as pullus Larus cachinnans on May 13 2022 at  IJsselmeer (De Kreupel), Holland. 
      Ringer: Leon Kelder. Recoveries:13-01-2023 Westkapelle (Vroon van Westkapelle), Zeeland, NL 5.132,00 N 326,00 E colourring read Merijn Loeve &  Pim Wolf
 13-03-2023 Burgh-Haamstede (Steursweg), Zeeland, NL 5.141,00 N 345,00 E colourring read Maarten Sluijter
 12-05-2023 Almere (De Vaart), Flevoland, NL 5.224,00 N 514,00 E colourring read Eric Roeland
 02-07-2023 IJsselmeer (De Kreupel), Noord-Holland, NL 5.247,00 N 513,00 E colourring read Leon Kelder
 09-06-2024 IJsselmeer (De Kreupel), Noord-Holland, NL 5.247,00 N 513,00 E colourring read Leon Kelder
 29-04-2024 IJsselmeer (De Kreupel), Noord-Holland, NL 5.247,00 N 513,00 E colourring read Leon Kelder
 09-06-2024 IJsselmeer (De Kreupel), Noord-Holland, NL 5.247,00 N 513,00 E colourring read Leon Kelder
 18-06-2025 IJmeer (Natuureiland), Noord-Holland, NL 5.222,00 N 500,00 E colourring read T. Horst & M. Muusse
 29-07-2025 Almere (De Blocq van Kuffeler), Flevoland, NL 5.225,00 N 513,00 E colourring read Maarten Hotting
 Bird from De Kreupel, nest M1 on island M. Data for this nest: 
        
      
      
      
      
      
      
      
      
      
        | Date: | Egg code | Height (mm) | Width (mm) | Comments | Metal NLA | Colour ring | Wing (mm) | Head+ bill (mm) | Mass (gr) |  
        |  |  |  |  |  |  |  |  |  |  |  
        | 14-4-2022 | A-egg | 72.5 | 52.8 | 3 eggs |  |  |  |  |  |  
        |  | B-egg | 68.7 | 54.8 |  |  |  |  |  |  |  
        |  | C-egg | 71.1 | 53.0 |  |  |  |  |  |  |  
        |  |  |  |  |  |  |  |  |  |  |  
        | 29-4-2022 |  |  |  | 3 eggs |  |  |  |  |  |  
        |  |  |  |  |  |  |  |  |  |  |  
        | 13-5-2022 |  |  |  | 3 pulli in nest | 5623529 | Red 1.6 |  | 63.3 | 171 |  
        |  |  |  |  |  | 5623530 | Red 1.7 | 53.5 | 71.5 | 276 |  
        |  |  |  |  |  | 5623531 | Red 1.8 |  | 68.2 | 210 |  
        |  |  |  |  |  |  |  |  |  |  |  
        | 17-5 - 19-5-2022 camera trap: | female Caspian Gull adult r-KB |  |  |  |  
        |  |  |  |  | male Caspian Gull |  |  |  |  
        |  |  |  |  |  |  |  |  |  |  |    |