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 Lelystad 204
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 204 positioned on dam 2, 13 mtr E of lighthouse, on top of dam, only 3 meters between nest 203 and nest 204.
- ID certain in 2022: both adult cachinnans.
- ID uncertian 2023: however, very early clutch indicates cachinnans, as do the chicks we ringed.
- ID in 2024: both parents are cachinnans.
| location | April 19th, 2022: location of nest (view from N). | April 15th, 2022: full clutch, 3 eggs. | April 21st, 2024: nest site. |
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| nest | April 9th, 2022: full clutch, 3 eggs. | April 29th, 2022: full clutch, 3 eggs. | April 21st, 2024: full clutch, with 3 eggs. |
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| April 15th, 2022: mark on stone. | April 19th, 2022: location of nest (view from N). | May 1st, 2022: location of nest (view from N). | |
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| March 31st, 2024: ad & sub-ad cachinnans | . | . | |
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| partner 1 | May 1st, 2022: adult cachinnans. | May 1st, 2022: adult cachinnans. | May 1st, 2022: adult cachinnans. |
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| partner 1 | April 23rd, 2024: adult cachinnans. | June 4th, 2024: adult cachinnans. | April 23rd, 2024: adult cachinnans. |
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| partner 2 | May 4th, 2022: adult cachinnans. | May 4th, 2022: adult cachinnans. | . |
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| partner 2 | June 4th, 2024: adult cachinnans. | June 4th, 2024: adult cachinnans. | June 4th, 2024: adult cachinnans. |
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| pullus | July 17th, 2022 pullus r[6.H]. | June 28th, 2022 pullus r[6.J]. | . |
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| pullus | May 27th, 2023: chick r[7.2]. | May 27th, 2023: chick r[7.3]. | May 27th, 2023: chick g[8|M]. |
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| pullus | May 7th, 2024: chick g[B|E]. | May 7th, 2024: chick g[B|F]. | May 14th, 2024: chick & parents at waterfront. |
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Visits and data 2022.
| nest 204 | date A egg: April 4 2022 | hatch A egg: May 2 2022 | ring pulli: May 9 2022 | |||||
| 15-04-22 | 3 eggs | A egg | 70,2 | 51,8 | tip bottom - 50 gr | nest 204 is 3 mtr E of 203. | ||
| B egg | 70,8 | 51,5 | tip bottom - 50 gr | code 204 sprayed on block. | ||||
| C egg | 68,7 | 51,8 | tip bottom - 40 gr | |||||
| 29-04-22 | 3 eggs | A egg | float - 3 mm | |||||
| B egg | float - 3 mm | |||||||
| C egg | float - 2 mm | |||||||
| 01-05-22 | adult cachinnans at nest. NOTE: 2x yellow-legged cachinnans of nest 203 close by. | |||||||
| 04-05-22 | adult cachinnans at nest. NOTE: male cachinnans of nest 203 has red spot stone as guarding stone. | |||||||
| 17-05-22 | no chicks found in vegetation. | |||||||
| metal | darvic | mass | wing | H+B | ||||
| 22-05-22 | pullus | .5625160 | r-6H | 537 | 125 | 90,6 | ||
| pullus | .5625161 | r-6J | 582 | 108 | 91,7 | |||
| 30-05-22 | pullus | r-6H swimming with sibling at N-side of dam 2. | ||||||
| pullus | r-6J swimming | |||||||
| 21-06-22 | pullus | r-6J & r6H swimming with sibling at N-side of dam 2. | ||||||
| 28-06-22 | r-6J & r-6H picture | |||||||
| 17-07-22 | pullus | r-6H picture. | ||||||
| egg sizes & volume 2023 | ||||||||||||
| SPECIES | NEST | A_length | A_width | A_volume | B_length | B_width | B_volume | C_length | C_width | C_volume | TOTAL NEST: | known parents? |
| cach x cach | 204-2023 | 72,5 | 52,3 | 99,85 | 70,6 | 52,3 | 97,23 | 67,3 | 51,5 | 89,87 | 286,95 | same as 2022 |
| ring pulli: May 10 | laying A egg: April 05 | hatch A egg: May 03 | ||||||||||
| catch: | date: | metal: | darvic: | mass: | wing: | head+bill: | ||||||
| Pullus | 11-5-2023 | 5.625.199 | r-72 | - | small chick, food is roach | |||||||
| Pullus | 11-5-2023 | 5.625.200 | r-73 | - | small chick | |||||||
| Pullus | 27-5-2023 | 5.625.199 | r-72 | 751 | ||||||||
| Pullus | 27-5-2023 | 5.625.200 | r-73 | 455 | ||||||||
| Pullus | 27-5-2023 | 5.625.261 | g-8|M | 480 | ||||||||
| 204-2023 | |||
| dam: | dam 2 west | ||
| location: | Is nest 204-2022. East nest of 203-204. 13 mtr E of lighthouse. | ||
| breeders: | cach x cach | ||
| OBSERVATIONS: | |||
| 9-4-2023 | nest: | 3 eggs measured. No watertest, ring chicks in 1st session. | |
| 26-4-2023 | nest: | 3 eggs. | |
| 11-5-2023 | pulli | 2 chicks ringed, 3rd chick? | |
| 27-5-2023 | pulli | 1x extra chick ringed; 3x chicks measured. | |
Visits and data 2024.
| NEST code | parent 1 | parent 2 | A_length | A_width | A_volume | B_length | B_width | B_volume | C_length | C_width | C_volume | TOTAL NEST: | |
| 204-2024 | cach | cach | 76 | 51,7 | 102,28 | 73,7 | 50,7 | 95,39 | 72,5 | 51,2 | 95,69 | 293,36 | |
| # eggs | A-egg | hatch | # ringed chicks | # all chicks | # fledged chicks | comments | |||||||
| 3 | 15-4-2024 | 13-5-2024 | |||||||||||
| dam: | dam 2 west | ||||||||||||
| location: | between lighthouse and blue sign, 5 mtr west of 248; was 204-2023. Red spot | ||||||||||||
| parents? | Same as 2023? | ||||||||||||
| ring pulli: | 18-May | ||||||||||||
| date | darvic | metal | location / nest# | species | sexe | age | wing | mass | head+ bill | bill | tarsus | gonys | greyscale |
| 07-05-2024 | g-B|E | .5631152 | 204 | PONT | 1CY | 153 | |||||||
| 07-05-2024 | g-B|F | .5631153 | 204 | PONT | 1CY | 115 | |||||||
| OBSERVATIONS: | |||||||||||||
| 31-03-2024 | adults: | 2x unringed cachinnans, one is immature. | |||||||||||
| 21-04-2024 | eggs: | 3 eggs, measured. | |||||||||||
| 02-05-2024 | eggs: | 3 eggs. | |||||||||||
| 07-05-2024 | chicks: | 2x ringed; 3rd chick not found. No eggs in nest. | |||||||||||
| 14-05-2024 | chicks: | no chicks near nest. Evening: 1x chick + 2x parents near waterfront, north side. | |||||||||||
| 04-06-2024 | chicks: | 2x chicks between blocks: g-B|E & g-B|F. | |||||||||||
| adult: | 2x present. Both are adult Caspian Gull (partner 1 has broad medial band P10). | ||||||||||||
| 18-06-2024 | chick: | g-B|E & g-B|F present at water. | |||||||||||