Larus cachinnans in the Netherlands
(last update: August 16, 2020)
Albert de Jong
Merijn Loeve
Roland-Jan Buijs
Thijs Horst
Leon Kelder
Mars Muusse
Cachinnans - nest Lelystad g-A|J (206, was y-X56A in 2022)
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 206 positioned on dam 2, 8 meters west of blue sign VHF20.
- ID certain in 2022: both cachinnans. One is female German ringed y-X56A. Y-X56A will move to nest 229 in season 2023 (few meters to the west).
- ID uncertain in 2023: one parent is certianly cachinnans, other partner limited proof.
- ID in 2024: Caspian Gulls.
| location | April 29th, 2022: nest location. | April 9th, 2023: nest with 3 eggs. | April 21st, 2024: location of nest. |
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| eggs | April 15th, 2022: 2 eggs. | May 9th, 2022: 3 eggs. Hatching day. | April 9th, 2023: full clutch: 3 eggs. |
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| . | April 21st, 2024: full clutch, with 3 eggs. | . | . |
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| partner 1 | April 29th, 2022: y-X56A is cachinnans. | April 11th, 2022: y-X56A is cachinnans. | April 29th, 2022: partner 1 y-X56A is cachinnans. |
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| partnber 1 | April 23rd, 2024: adult cachinnans. | April 23rd, 2024: adult cachinnans. | April 30 2024: female cachinnans trapped: g-A|J. |
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| partner 2 | April 29th, 2022: partner 2 is cachinnans. | April 29th, 2022: partner 2 is cachinnans. | April 29th, 2022: partner 2 is cachinnans with broad medial band on P10. |
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| partner 2 | April 4th, 2023: adult Caspian Gull. | . | . |
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| pullus | June 28th, 2022: r-5.3 fledged. | June 28th, 2022: r-5.4 fledged. | June 28th, 2022: r-5.5 fledged. |
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| pullus | October 20th, 2023: r-7.W fledged. | October 20th, 2023: r-7.X fledged. | May 14 2024: pullus g-B|Y. |
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| pullus | May 14 2024: pullus g-B|Z. | . | . |
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Visits and data.
| visits in 2022: | ||||||
| 11-04-2022 | yellow ring at this location, can it be y-X56A? | |||||
| 12-04-2022 | 2 adults near nest. | |||||
| egg no: | width (mm): | length (mm): | volume (cm3): | |||
| 15-04-2022 | A | 52,2 | 74,5 | -- | 20 - tip bottom | 3 eggs |
| B | 52,7 | 74,2 | 10 - tip bottom | |||
| sum nest: | -- | |||||
| 19-04-2022 | 2 adults near nest. | |||||
| egg no: | 3 eggs, 2 adults (incl y-X56A). | |||||
| 29-04-2022 | A | float - 3 mm | ||||
| B | float - 2 mm | |||||
| C | float - halfway | |||||
| 09-05-2022 | 3 eggs. Hatching day for B egg. Small hole in egg. | |||||
| metal | colour | mass | ||||
| 17-05-2022 | .5625139 | r-54 | 251 | |||
| .5625140 | r-55 | 181 | ||||
| .5625141 | r-53 | 225 | ||||
| 02-06-2022 | adult y-X56A present on bread. | |||||
| 17-06-2022 | r-55 flying around; parent y-X56A ferociously protect the chick. | |||||
| 21-06-2022 | adult y-X56A present. Chicks r-53, r-54, r-55 swimming around. | |||||
| food: we catch r-55, throws up fish food. | ||||||
| 28-06-2022 | adult y-X56A present. Chicks r-53 & r-55 photographed. | |||||
| 12-07-2022 | Chick r-55 photographed. | |||||
| 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 | 206 | 71,3 | 50,5 | 91,55 | 67,3 | 51,3 | 89,18 | 67 | 48,8 | 80,34 | 261,07 | one is 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: | bill: | gonys: | greytone: | |||
| Pullus | 11-5-2023 | NLA5625194 | r 7.W | |||||||||
| Pullus | 11-5-2023 | NLA5625195 | r 7.X | |||||||||
| Pullus | 18-6-2023 | r-7X | ||||||||||
| Pullus | 18-6-2023 | r-7W | ||||||||||
| 206 | (was X56A) | |
| dam: | dam 2 west | |
| location: | 8 mtr W of blue sign VHF20, south side, on blocks | |
| breeders: | cach x cach | |
| OBSERVATIONS: | ||
| 26-4-2023 | nest: | 3 eggs. |
| 27-4-2023 | y-X56A is NOT the parent (27/4 confirmed). | |
| 27-4-2023 | 3 eggs measured. Watertest C-egg: 20 - tip bottom | |
| 11-5-2023 | pull: | 2 kuikens geringd, 3e kuiken? |
| 11-5-2023 | r-7X: baars en voorn uitgebraakt | |
| 18-5-2023 | nest: | nest empty, no chicks found |
| 27-mei | nest: | nest empty, no chicks found |
| 18-6-2023 | pull: | r-7X & r-7W present, 2 birds fledged. |
| 25-6-2023 | pull: | r-7X and r-7W present, 2 birds fledged. |
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: | |
| g-A|J (206) | cach | cach | 66,5 | 51 | 87,09 | 70,3 | 50,7 | 90,99 | 70,3 | 48,3 | 82,58 | 260,65 | |
| 2024 | # eggs | A-egg | hatch | # ringed chicks | # all chicks | # fledged chicks | comments | ||||||
| 3 | 15-4-2024 | 13-5-2024 | |||||||||||
| dam: | dam 2 west | ||||||||||||
| location: | 8 mtr SW of Blue sign, was 206-2023/2022. | ||||||||||||
| parents? | Same as 2023? | ||||||||||||
| ring pulli: | 18-May | ||||||||||||
| date | darvic | metal | location / nest# | species | sexe | age | wing | mass | head+ bill | bill | tarsus | gonys | greyscale |
| 30-04-2024 | g-A|J | .5631207 | Dam 2 | PONT | F | >4CY | 439 | 919 | 122,0 | 53,1 | 67,0 | 18,5 | 5 |
| 14-05-2024 | g-B|Y | .5631176 | nest 206 | PONT | 1CY | 156 | |||||||
| 14-05-2024 | g-B|Z | .5631177 | nest 206 | PONT | 1CY | 96 | |||||||
| 04-06-2024 | g-B|Y | .5631176 | nest 206 | PONT | 1CY | 198 | 799 | 102,0 | |||||
| OBSERVATIONS: | |||||||||||||
| 12-04-2024 | nest | ready, but still empty | |||||||||||
| 21-04-2024 | eggs: | 3 eggs, measured. | |||||||||||
| adult: | 2x unringed cachinnans. | ||||||||||||
| 30-04-2024 | adults: | trapped female Caspian Gull, now g-A|J. | |||||||||||
| 02-05-2024 | eggs: | 3 eggs. | |||||||||||
| 07-05-2024 | eggs: | 3x. | |||||||||||
| 14-05-2024 | chicks: | 2x ringed and measured. | |||||||||||
| 04-06-2024 | pullus: | g-B|Y present, measured. | |||||||||||
| adult: | 1x present. | ||||||||||||
| 18-06-2024 | chick: | trapped g-B|Y at water. | |||||||||||