Larus cachinnans in the Netherlands
(last update: August 16, 2020)
Albert de Jong
Merijn Loeve
Roland-Jan Buijs
Thijs Horst
Leon Kelder
Mars Muusse
Caspian Gull cachinnans P:U60 4CY-8CY, March 2021 - April 2025, Lelystad & Almere, the Netherlands. Picture: Thijs Horst, Mars Muusse & Albert de Jong.
Metal ring PLG DN35458 and yellow P:U60, ringed as pullus on June 09 2018 in a mixed Caspian Gull colony "Larus cachinnans kolonia" with cachinnans dominance, at river Wisla, POLAND, by ringer Lukasz Bednarz.
In all respects, y[P:U60] is cachinnans, no indication for hybrid.
Breeding in nest y[P:U60].
From 2021 onwards, breeding in colony Lelystad, nest always at the same spot (2021-2024).
| 09/06/2018 | Rz.Wisła,Zastów Karczmiski,Opole Lubelskie POLAND (LUBELSKIE) | Łukasz Bednarz |
| 03/08/2018 | Składowisko odpadów PUO Świdnica, Sulisławice POLAND (DOLNOŚLĄSKIE) | Benedykt Adamczyk |
| 09/09/2018 | Dreba-Plother-Teichgebiet: Kohlungsteich GERMANY (THÜRINGEN) | HIDDENSEE .DEH Schoder, Frank |
| 17/04/2020 | Salzgitter-Heerte:Deponie GERMANY (NIEDERSACHSEN: BRAUNSCHWEIG) | Gerhard Braemer |
| 16/05/2020 | Orava lake, Bird island SLOVAKIA (NAMESTOVO) | Miro Demko |
| 19/03/2021 | Almere: de Vaart NETHERLANDS (FLEVOLAND) | Eric Roeland |
| 23/03/2021 | Almere: de Vaart NETHERLANDS (FLEVOLAND) | Eric Roeland |
| 24/03/2021 | Lelystad NETHERLANDS (FLEVOLAND) | Mars Muusse Albert de Jong |
| 04/05/2021 | Almere de Vaart NETHERLANDS (FLEVOLAND) | thijs horst |
| 04/08/2021 | Trintelzand NETHERLANDS (FLEVOLAND) | D. B. |
| 09/10/2021 | Almere: de Vaart NETHERLANDS (FLEVOLAND) | Eric Roeland |
| 21/06/2022 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst |
| 19/09/2022 | dike Enkhuizen-Lelystad NETHERLANDS (FLEVOLAND) | Guus van Duin |
| 05/02/2023 | Almere: de Vaart NETHERLANDS (FLEVOLAND) | Eric Roeland |
| 13/02/2023 | Almere de Vaart NETHERLANDS (FLEVOLAND) | thijs horst |
| 24/02/2023 | Almere: de Vaart NETHERLANDS (FLEVOLAND) | Eric Roeland |
| 26/03/2023 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 04/04/2023 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 06/04/2023 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse Albert de Jong |
| 09/04/2023 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 13/05/2023 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 27/05/2023 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse Merijn Loeve |
| 18/06/2023 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 25/06/2023 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst |
| 08/07/2023 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 18/07/2023 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 15/12/2023 | Almere: de Vaart NETHERLANDS (FLEVOLAND) | Eric Roeland |
| 16/01/2024 | Almere de Vaart NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 18/01/2024 | Almere de Vaart NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 19/03/2024 | Lelystad, Bataviahaven NETHERLANDS (FLEVOLAND) | Maarten Hotting |
| 19/03/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 20/03/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 25/03/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst |
| 26/03/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 30/03/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Harry Kuipers |
| 30/03/2024 | Lelystad, Bataviahaven NETHERLANDS (FLEVOLAND) | Harry Kuipers |
| 31/03/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 08/04/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse Gabi Martin, Theo Muusse |
| 11/04/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | J. de L. |
| 21/04/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 23/04/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 26/04/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse Albert de Jong |
| 02/05/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse, Albert de Jong |
| 05/05/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse, Fred Cottaar |
| 07/05/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 17/05/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst |
| 31/05/2024 | Lelystad Colony Oostvaardersdiep NETHERLANDS (FLEVOLAND) | Merijn Loeve Thijs Horst |
| 04/06/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse Albert de Jong |
| 18/06/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 24/06/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst |
| 25/06/2024 | Bataviahaven, Lelystad NETHERLANDS (FLEVOLAND) | thijs horst Mars Muusse |
| 30/07/2024 | De Kreupel NETHERLANDS (FLEVOLAND) | thijs horst Jeroen van Assema |
In 2021 breeding bird at colony Lelystad, the Netherlands. Y-P:U60 is a female, partner is large unringed adult male Caspian Gull cachinnans in nest 68.
This nest is in a section with large bolders and blocks, nest not visible from the water and many Lesser Black-backed Gulls breeding around and nests at close range.
Chicks can hide in numerous crevices underneath the blocks, making them hard to find. Visits and data for this nest in 2021:
| date: | egg no: | width (mm) | length (mm) | volume (cm3): | water test on May 7th: | |
| 06-05-2021 | A | 50,1 | 73,3 | 91,34 | 90 - tip at bottom. | 2 eggs in the nest, one partner is y[P:u60] 4CY cachinnans. |
| B | 49,2 | 70,9 | 92,28 | 90 - floating halfway. | ||
| sum nest: | -- | |||||
| 13-05-2021 | No visit, Camilla is trapping a spoonbill. | |||||
| 15-05-2021 | 2 eggs, still complete. y[P:U60] and partner is large Caspian Gull male. | |||||
| 28-05-2021 | nest is empty. y[P:U60] and partner both alarming. Chicks not found between all those blocks. | |||||
| 08-06-2021 | No activity visible from south side. Later, from north side y[P:U60] flying around. | |||||
Data for 2022 nest y-PU60: |
||||||
| 12-04-2022 | y-P:U60 present. Nest not excatly located yet, but close to place of previous season. | |||||
| egg no: | width (mm) | length (mm) | volume (cm3): | water test on April 12th: | ||
| 15-04-2022 | A | 51,8 | 72,9 | -- | 40 - tip at bottom. | 3 eggs in the nest. |
| B | 51,3 | 71,6 | -- | 30 - tip at bottom. | Extrapolation: 1st egg laid on April 9th; 1st egg will hatch on May 7th. Ring: May 14th. | |
| C | 50,1 | 70,5 | -- | 20 - tip at bottom. | ||
| sum nest: | -- | |||||
| 27-04-2022 | A | 4 mm- floating. | 3 eggs in the nest. | |||
| B | 3 mm- floating. | |||||
| C | 2 mm- floating. | |||||
| 09-05-2022 | y-P:U60 present. | |||||
| metal | darvic | mass | ||||
| 17-05-2022 | .5625114 | r-5T | 293 | Much fish around nest, incl Roach / Rudd and Perch. | ||
| .5625115 | r-5S | 191 | ||||
| .5625116 | r-5R | 329 | ||||
| metal | darvic | mass | ||||
| 30-05-2022 | .5625116 | r-5R | 680 | y-P:U60 and partner are present, together with (at least) . | ||
| 02-06-2022 | 2 adults and 3 large chicks present. | |||||
| 17-06-2022 | 2 adults and (at least) 2 chicks present. | |||||
| 21-06-2022 | 2 adults and all 3 large chicks r-5R, r-5S & r-5T present. | |||||
| 28-06-2022 | 2 adults and all 3 large chicks r-5R, r-5S & r-5T present. | |||||
| 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 | PU60 | 76,6 | 51 | 100,32 | 69,2 | 50,3 | 88,15 | 72,1 | 51,3 | 95,54 | 284,01 | same as 2022 |
| ring pulli: 10-mei | laying A egg: 5-apr | hatch A egg: 3-mei | ||||||||||
| date: | metal: | darvic: | mass: | wing: | head+bill: | |||||||
| pullus | 11-05-2023 | NLA5556478 | r 8.3 | -- | -- | -- | ||||||
| pullus | 11-05-2023 | NLA5556479 | r 8.5 | -- | -- | -- | ||||||
| pullus | 18-05-2023 | 5556495 | G-7|C | 550 | -- | 89,8 | ||||||
| pullus | 27-05-2023 | 5556495 | G-7|C | 955 | -- | -- | ||||||
| dam: | dam 1 blocks | |
| location: | location is PU60-2022. Red spot on block near nest. | |
| breeders: | cach x cach | |
| OBSERVATIONS: | ||
| 09-04-2023 | adult: | female PU60 & adult male cach present. Red spot renewed. |
| nest: | 3 eggs measured. Watertest C-egg: 20 - tip bottom. | |
| 11-05-2023 | pulli: | 2 chicks ringed, is there a 3rd chick? |
| 13-05-2023 | adult: | PU60 & male cach present. |
| 18-05-2023 | pulli: | 1 chick ringed G-7|C, R-85 present. |
| 27-05-2023 | pulli: | 1x control chick G-7|C. |
| 18-06-2023 | pulli: | r-83, r-85, g7|C present, with 2 adults (incl PU60). Fledged: 3 juveniles. |
| 25-06-2023 | pulli: | family complete, 3x chicks 2x parents. Result 2023: 3x fledged juveniles. |
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: | |
| P:U60 2024 | cach | cach | 75 | 52,6 | 104,48 | 74,6 | 51,7 | 100,40 | 72 | 50,7 | 93,19 | 298,06 | |
| # eggs | A-egg | hatch | # ringed chicks | # all chicks | # fledged chicks | comments | |||||||
| 3 | 10-4-2024 | 6-5-2024 | |||||||||||
| dam: | dam 1 blocks | ||||||||||||
| location: | location is PU60-2022/2023. Red spot + P on block near nest. | ||||||||||||
| parents? | same as 2023 | ||||||||||||
| ring pulli: | 11-May | ||||||||||||
| date | darvic | metal | location / nest# | species | sexe | age | wing | mass | head+ bill | bill | tarsus | gonys | greyscale |
| 14-05-2024 | g-B|8 | .5631193 | nest PU60 | PONT | 1CY | 282 | |||||||
| 14-05-2024 | g-B|9 | .5631194 | nest PU60 | PONT | 1CY | ||||||||
| 04-06-2024 | g-B|8 | .5631193 | nest PU60 | PONT | 1CY | 260 | 839 | 108,7 | |||||
| 04-06-2024 | g-B|9 | .5631194 | nest PU60 | PONT | 1CY | 179 | 514 | 95,7 | |||||
| OBSERVATIONS: | |||||||||||||
| 12-04-2024 | eggs: | 2 eggs, measured. | |||||||||||
| 21-04-2024 | eggs: | 3 eggs, measured | |||||||||||
| adult: | both parents present. PU60 (incubating) & unringed male (guarding). | ||||||||||||
| 23-04-2024 | adult: | both parents present. | |||||||||||
| 07-05-2024 | eggs: | 2 eggs hatching, 1 chick just out, not ringed. | |||||||||||
| 14-05-2024 | chicks: | 2x ringed, 3rd chick not found. | |||||||||||
| 31-05-2024 | chicks: | g-B|8, g-A|9 present. | |||||||||||
| 04-06-2024 | chicks: | g-B|8 & g-B|9 present. measured. | |||||||||||
| 18-06-2024 | chicks: | g-B|8 present. | |||||||||||
below: Caspian Gull cachinnans P:U60 8CY, April 12 2025, colony Lelystad, the Netherlands. Picture: Thijs Horst.
below: Caspian Gull cachinnans P:U60 8CY, April 04 2025, colony Lelystad, the Netherlands. Picture: Mars Muusse & Thijs Horst.
below: Caspian Gull cachinnans P:U60 8CY, March 21 2025, colony Lelystad, the Netherlands. Picture: Thijs Horst.
below: Caspian Gull cachinnans P:U60 8CY, March 16 2025, colony Lelystad, the Netherlands. Picture: Thijs Horst & Mars Muusse.
Back at same location as nest in 2024. And, just for no good reason, finally reacting to bread, for only 2 seconds.
.JPG)
below: Caspian Gull cachinnans P:U60 7CY, July 30 2024, colony De Kreupel, the Netherlands. Picture: Thijs Horst.
below: Caspian Gull cachinnans P:U60 7CY, June 25 2024, colony Lelystad, the Netherlands. Picture: Thijs Horst & Mars Muusse.
Together with the only fledged chick for 2024: g-B|8.
below: Caspian Gull cachinnans P:U60 6CY, July 18 2023, Lelystad, the Netherlands. Picture: Thijs Horst & Mars Muusse.
below: Caspian Gull cachinnans P:U60 6CY, July 08 2023, Lelystad, the Netherlands. Picture: Thijs Horst & Mars Muusse.
below: Caspian Gull cachinnans P:U60 6CY, April 05 2023, Lelystad, the Netherlands. Picture: Thijs Horst.
below: Caspian Gull cachinnans P:U60 6CY, February 13 2023, Almere, the Netherlands. Picture: Thijs Horst & Mars Muusse.
With male partner at Almere dump.
below: Caspian Gull cachinnans P:U60 5CY, June 21 2022, Lelystad, the Netherlands. Picture: Thijs Horst.
below: Caspian Gull cachinnans P:U60 5CY, May 30 2022, Lelystad, the Netherlands. Picture: Mars Muusse.
below: Caspian Gull cachinnans P:U60 5CY, April 27 2022, Lelystad, the Netherlands. Picture: Mars Muusse.
below: Caspian Gull cachinnans P:U60 4CY, June 08 2021, Lelystad, the Netherlands. Picture: Mars Muusse & Albert de Jong.
below: Caspian Gull cachinnans P:U60 4CY, May 15 2021, Lelystad, the Netherlands. Picture: Mars Muusse & Mónika Ballmann.
below: Caspian Gull cachinnans P:U60 4CY, March 30 2021, Almere, the Netherlands. Picture: Mars Muusse.
Y-P:U60 and her partner present at a small local waste dump at Almere, distance about 17 km's from the colony.
below: Caspian Gull cachinnans P:U60 4CY, March 24 2021, Lelystad, the Netherlands. Picture: Mars Muusse & Albert de Jong.
Also present today: w-327:U from Czechia.
