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-FL.
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-FL positioned on dam 1 west section: opposite floodgate, close to nest 92, on top of dam 1.
- ID certain in 2025: female is 5CY cachinnans r-FL (offsping nest 14-2021), and male is adult cachinnans.
| nest | April 21 2025: 3 eggs. | April 21 2025: 3 eggs. | . |
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| partner 1 | April 21 2025: 5CY female Caspian Gull r-FL. | March 21 2025: 5CY female Caspian Gull r-FL. | March 21 2025: 5CY male Caspian Gull & Caspian r-FL. |
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| partner 2 | April 12 2025: Caspian r-FL & male Caspian Gull. | April 12 2025: 5CY male Caspian Gull. | April 12 2025: 5CY male Caspian Gull. |
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| pullus | May 13 2025: chick G-N|3. | August 04 2025: chick G-N|4. Fledged. | August 04 2025: chick G-N|5. Fledged. |
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Data for nest r-FL 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:
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# eggs | |
| r-FL | cach | cach | 70,5 | 50,6 | 69,9 | 49,2 | 69 | 48,8 | 3 | |||||
| dam: | dam 1 west | |||||||||||||
| location: | opposite floodgate, dam 1, close to nest 92
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| parents: | new, female r-FL is pullus nest 14-2021. Male is unringed Caspian Gull.
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| ringed: | ||||||||||||||
| date | darvic | metal | location / nest# | species | sexe | age | wing | mass | head+ bill | bill | tarsus | gonys | greyscale | |
| 21-04-2025 | r-FL | 5550684 | r-FL dam 1 | cach | F | 5CY | 429 | 949 | 128 | 56,1 | 68,3 | 17,6 | 5,5 | |
| 13-05-2025 | G-N|3 | 5641046 | r-FL | PONT | pullus | 170 | ringed pullus
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| 13-05-2025 | g-N|4 | 5641047 | r-FL | PONT | pullus | 176 | ringed pullus
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| 13-05-2025 | g-N|5 | 5641048 | r-FL | PONT | pullus | 85 | ringed pullus
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OBSERVATIONS:
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| 12-04-2025 | nest | r-FL & unringed male Caspian Gull
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| 21-04 | nest | r-FL breeding, nest 3 eggs
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| location | broom placed in Blackberry at 2 meters from nest, dam 1
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| adult | CONTROL. Attempt to trap unringed male, but we caught r-FL instead
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| eggs | 3 eggs, measured
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| 23-04 | nest | r-FL incubating, Unringed male guarding
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| 25-04 | adult | CONTROL. Attempt to trap unringed male, but we caught r-FL second time this season
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| 09-06 | chicks | adults with at least 1 chick on water
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