Larus cachinnans in the Netherlands
(last update: August 16, 2020)
Albert de Jong
Leon Kelder
Roland-Jan Buijs
Thijs Horst
Merijn Loeve
Mars Muusse
Cachinnans - nest r-7F
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 r-7F positioned on dam 2 east section, 2 meters east of nest 55, close to tarmac. Large boulder next to nest is lookout-post.
- ID certain in 2025: male is 4CY cachinnans r-7F (from nest 026-2022), and female is adult cachinnans.
| nest | April 21 2025: nest with 2 eggs. | April 21 2025: nest with 2 eggs. | . |
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| partner 1 | July 09 2025: male 4CY cachinnans r-7F. | April 01 2025: male 4CY cachinnans r-7F. | March 25 2025: male 4CY cachinnans r-7F. |
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| partner 2 | March 25 2025: pair cachinnans, with male r-7F. | April 25 2025: female cachinnans. | April 25 2025: female cachinnans. |
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| partner 2 | April 25 2025: female cachinnans. | April 25 2025: female cachinnans. | April 25 2025: female cachinnans. |
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Data for nest r-7F in 2025:
| 2025 | parent 1 | parent 2 | A_length | A_width | A_volume | B_length | B_width | B_volume | C_length | C_width | C_volume | TOTAL NEST: | # eggs | |
| r-7F | cach | cach | 74 | 50 | 72,7 | 50,6 | 68,6 | 49,7 | 3 | |||||
| dam: | dam 2 east | |||||||||||||
| location: | 2 meters east of nest 55, close to tarmac. Large boulder next to nest is lookout-post.
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| parents: | new nest: r-7F is pullus nest 26-2022. Blue Bucket dam 1 T-split.
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| OBSERVATIONS: | ||||||||||||||
| 25-03-2025 | adult | r- F7 at nest site. | ||||||||||||
| 01-04-2025 | adult | r- F7 at nest site. | ||||||||||||
| 04-04-2025 | adult | r- F7 at nest site. | ||||||||||||
| 21-04-2025 | eggs | 2x eggs measured
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| 28-04-2025 | eggs | 3x measured | ||||||||||||
| 01-05-2025 | adult | 7F present | ||||||||||||
| 08-05-2025 | adult | both partners present
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| 25-05-2025 | nest | no chicks found, nest empty
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