| Coordinator: Albert de Jong
 Merijn Loeve
 Roland-Jan Buijs
 Thijs Horst
 Leon Kelder
 Mars Muusse
 Home Project InfoInternational trend
 National trend
 Site characteristics
 Breeding biology
 Fecundity
 Food resources
 Nonbreeding season
 Breeding species
 Hybrid scores
 Ring codes
 Future
 | Caspian Gull cachinnans K.0 1CY, May 14 2021, De Kreupel  - M, the Netherlands. Picture: Leon Kelder. Red  tibia  ring r[K.0] and metal NLA 5.556.734, ringed as pullus Larus cachinnans on May 14 2021 at nest KA 21 in colony De Kreupel, the Netherlands. Ringer: Leon Kelder.ID is uncertain: father is  Caspian Gull cachinnans (ringed r-K.A), mother is unknown.
 Recoveries:20-05-2021 IJsselmeer (De Kreupel), Noord-Holland, NL 5.247,00 N 513,00 E captured by ringer Leon Kelder
 20-10-2024 Nieuwegein (Lekkanaal), Utrecht, NL 5.201,00 N 506,00 E colourring read Frank Engelen
 
 
      
      
      
      
      
      
      
      
      
      
      
        | Date: | details: |  |  |  |  |  |  
        |  |  |  |  |  |  |  |  
        | 9-4-2021 | 2 eggs in nest. | egg no: | width (mm): | length (mm): | volume (cm3): |  |  
        |  | https://waarneming.nl/observation/210427028/ | A egg | 50.8 | 67.0 |  |  |  
        |  |  | B egg | 52.1 | 70.8 |  |  |  
        |  |  |  |  |  |  |  |  
        |  |  |  |  |  |  |  |  
        |  |  |  |  |  |  |  |  
        | 23-4-2021 | 3 eggs in nest. | egg no: | width (mm): | length (mm): | volume (cm3): |  |  
        |  | https://waarneming.nl/observation/210427028/ | A egg | 51.0 | 67.1 |  |  |  
        |  |  | B egg | 52.4 | 70.8 |  |  |  
        |  |  |  | 52.1 | 68.9 |  |  |  
        |  |  |  |  |  |  |  |  
        |  |  |  |  |  |  |  |  
        |  | Attempt to trap breeding adult. Adult trapped. | metal: | tibia: | wing: | head + bill: | bill: |  
        |  | Adult male   Caspian Gull cachinnans. | NLA 6.211.436 | Red-K.A | 461 | 132.0 | 63.0 |  
        |  |  | mass: | moult score: | bill height: | grey scale: | Tarsus: & Swob: |  
        |  |  | -- | 10x0 | 19.3 | 6 | 73.0 & 1078 |  
        |  |  |  |  |  |  |  |  
        | 14-5-2021 | 2 pulli in nest. | metal: | tibia: | mass (gr): | head + bill: | tarsus: |  
        |  | https://waarneming.nl/observation/214663945/ | NLA 5.556.734 | r-K.0 | 216 | 69.3 | 40.3 |  
        |  |  | NLA 5.556.735 | r-K.1 | 169 | 62.2 | 35.8 |  
        |  |  |  |  |  |  |  |  
        | 20-5-2021 | 3 pulli in direct surrounding of nest. | metal: | tibia: | mass (gr): | head + bill: | wing: |  
        |  | https://waarneming.nl/observation/214710893/ | NLA 5.556.734 | r-K.0 | 531 | 85.9 | 86.0 |  
        |  |  | NLA 5.556.735 | r-K.1 | 415 | 77.7 | 76.0 |  
        |  |  | NLA 5.556.762 | b-D|+ | 513 | 86.2 | 84.5 |  
        |  |  |  |  |  |  |  |  
        |  |  |  |  |  |  |  |  
        |  |  |  |  |  |  |  |  
        |  |  |  |  |  |  |  |  
        |  |  |  |  |  |  |  |  
        |  |  |  |  |  |  |  |  |