| Coordinator: Albert de Jong
 Merijn Loeve
 Roland-Jan Buijs
 Thijs Horst
 Leon Kelder
 Mars Muusse
 Home Project InfoLocation Lelystad
 Location De Kreupel
 2019 Lelystad
 2020 Lelystad
 2021 Lelystad
 Coded nests  Lelystad
 2020 De Kreupel
 2021 De Kreupel
 Coded nests  De Kreupel
 All ring codes 2020
 All ring codes 2021
 Lelystad 2020:nest 001
 nest 002 yPNED
 nest 003
 nest 005 yPLDP
 nest 006 yPESV
 nest 008 gXLDT
 nest 009
 nest 011
 nest 012
 nest 013
 nest 014
 nest 015
 nest 016
 nest 017
 nest 018
 nest 021
 nest 025
 nest 027
 nest 028
 nest 029
 nest 031
 nest 032
 nest 033
 nest 034
 nest 035
 nest 036
 nest 037
 nest 038
 nest 039
 pair A
 pair B
 Lelystad 2021nest  y-PNED
 nest  y-PLDP
 nest  y-PHSV
 nest  y-P:A02
 nest  y-P:U60
 nest zy-MT
 nest  r-FB
 nest  r-FC
 nest 001
 nest 003
 nest  006
 nest 011
 nest 012
 nest 013
 nest 014
 nest 015
 nest 016B
 nest 017
 nest 018
 nest  019
 nest 021
 nest 034
 nest 035
 nest 038
 nest 040
 nest 041
 nest 042
 nest 044
 nest 045
 nest 046
 nest 047
 nest 048
 nest 053
 nest 055
 nest 056
 nest 058
 nest 060
 nest 062
 nest 063
 nest 065
 nest 066
 nest 067
 nest 072
 |  Cachinnans - nest Lelystad  045
General remarks: 
                  Eggs: Volume measured by  Stonehouse (1964) and  Spaans & Spaans (1975), which make comparison possible with data from Texel (Camphuysen pers comm 16.04.2020).Nest 045 never found, but positioned at  breakwater 2, 7 meters west of coded block 17. Most of April and May, only a guarding bird at blocks (was believed to may belong to nest 17 for some time).        ID  uncertain in season 2021,   Caspian Gull type, likely hybrid. 
        
          | location 2021 | March 30th, 2021 multiple cachinnans guarding. | May 13th, 2021 guarding cachinnans and michahellis. | . |  
          |  |  |  |  |  
          | partner 1 | May 13th, 2021: Caspian Gull type. | May 13th, 2021: Caspian Gull type. | May 13th, 2021: Caspian Gull type. |  
          |  |  |  |  |  Visits and data. 
        
        
        
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          | 26-04-2021 | This day old  nest 17 becomes new nest 17 with Herring Gull sub-adult. |  |  |  |  |  |  |  |  |  
          |  | 7 meters west of block  '17', on blocks at waterfront again the guarding Caspian Gull type (probably hybrid). Partner of the Herring Gull? But never interaction with nest 17. |  |  
          | 13-05-2021 | Guarding bird again present. |  |  |  |  |  |  
          | 15-05-2021 | Guarding bird again present. |  
          | 08-06-2021 | The guarding bird does not belong to nest 17. Now 2 Caspian Gull types present which behave as kind of couple. Assigned to new code: nest 45 (although nest never found). |  |  |  |  
          |  | Cachinnans type bird may be late breeder or may be only prospector in colony? |  |  |  |  |  |