Larus cachinnans in the Netherlands

(last update: August 16, 2020)

Coordinators:
Albert de Jong
Leon Kelder
Roland-Jan Buijs
Thijs Horst
Merijn Loeve
Mars Muusse

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Caspian Gull cachinnans T|B 1CY, 2025, the Netherlands. Picture: Thijs Horst, Mars Muusse & Fred Cottaar.

You can participate in this project too! Please send in your observations of colour ringed birds to: ring@buijsecoconsult.nl

Tibia G-T|B and metal NLA 5.641.064, ringed as pullus Larus cachinnans on May 13 2025 at Lelystad, the Netherlands. Ringed by Roland-Jan Buijs ringing team (Mars Muusse / Thijs Horst / Fred Cottaar).
Mother: adult Caspian Gull g-N|F.
Father: adult Caspian Gull g-N|D.
Nest: g-N|D & g-N|F (034). In 2025, G-T|A & G-T|B fledged, g-T|C not seen after ringing. Fledging rate for this nest 2025 = 2,0.

Recoveries:
13-06-2025 Lelystad (Bataviahaven), Flevoland, NL 5.230,00 N 525,00 E colourring read Thijs Horst
14-06-2025 Lelystad (Bataviahaven), Flevoland, NL 5.230,00 N 525,00 E colourring read T. Horst & M. Muusse
25-06-2025 Lelystad (Bataviahaven), Flevoland, NL 5.230,00 N 525,00 E colourring read Thijs Horst
29-06-2025 Lelystad (Bataviahaven), Flevoland, NL 5.230,00 N 525,00 E colourring read T. Horst & M. Muusse
30-06-2025 Lelystad (Bataviahaven), Flevoland, NL 5.230,00 N 525,00 E colourring read Thijs Horst
09-07-2025 Lelystad (Bataviahaven), Flevoland, NL 5.230,00 N 525,00 E colourring read T. Horst & M. Muusse
21-07-2025 Velsen (Strand Noordpier), Noord-Holland, NL 5.228,00 N 433,00 E colourring read Fred Cottaar
11-08-2025 Cromer (Strand), Norfolk, ENGELAND 5.255,00 N 118,00 E colourring read Andy Hale
12-08-2025 Cromer (Strand), Norfolk, ENGELAND 5.255,00 N 118,00 E colourring read Andy Hale
13-08-2025 Cromer (Strand), Norfolk, ENGELAND 5.255,00 N 118,00 E colourring read Neil Morris
14-08-2025 Cromer (Strand), Norfolk, ENGELAND 5.255,00 N 118,00 E colourring read Andy Hale
18-08-2025 Cromer (Strand), Norfolk, ENGELAND 5.255,00 N 118,00 E colourring read Andy Hale
22-08-2025 Cromer (Strand), Norfolk, ENGELAND 5.255,00 N 118,00 E colourring read Andy Hale
23-08-2025 Cromer (Strand), Norfolk, ENGELAND 5.255,00 N 118,00 E colourring read Andy Hale
24-08-2025 Cromer (Strand), Norfolk, ENGELAND 5.255,00 N 118,00 E colourring read Andy Hale
29-08-2025 Cromer (Strand), Norfolk, ENGELAND 5.255,00 N 118,00 E colourring read Andy Hale
01-09-2025 Cromer (Strand), Norfolk, ENGELAND 5.255,00 N 118,00 E colourring read Andy Hale
05-09-2025 Cromer (Strand), Norfolk, ENGELAND 5.255,00 N 118,00 E colourring read Andy Hale
06-09-2025 Cromer (Strand), Norfolk, ENGELAND 5.255,00 N 118,00 E colourring read Andy Hale
07-09-2025 Sheringham (Strand), Norfolk, ENGELAND 5.256,00 N 112,00 E colourring read Pete Geary

Visits and data 2025 g-N|D & g-N|F (034).

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
g-N|D & g-N|F (034) cach 69 50,8 67,7 52,3 66 48,7 3
dam:
dam 1 blocks
location:
Nest 34 Roodflapje, at blocks east part, nest red flag
ouders:
same as 2024, this year trapped. Now male is g-N|D and female is g-N|F.
ringed:
date darvic metal location / nest# species sexe age wing mass head+ bill bill tarsus gonys greyscale
28-04-2025 g-N|D 5641013 34, roodflapje PONT M >4CY 474 1200 132 62,1 76 20 5
28-04-2025 g-N|F 5641014 34, roodflapje PONT F >4CY 436 972 123,8 54,4 66,6 18,8 7
13-05-2025 g-T|A 5641063 34 PONT pullus 376
13-05-2025 g-T|B 5641064 34 PONT pullus 373
13-05-2025 g-T|C 5641065 34 PONT pullus 270
09-06-2025 G-T|A 5641063 PONT pullus 764 CONTROL
14-06-2025 G-T|A PONT pullus 851 CONTROL
OBSERVATIONS:
23-04-2025 eggs
3 eggs, measured, Small sizes!
28-04 eggs 3 eggs
adult
trapped both adult at nest nowg-N|D and g-N|F
food
g-N|D hasa bolus of chicken + fish, g-N|F has bolus of fish (roach and perch)
01-05 adult both partners present
08-05 adult
both partners present
13-05 chicks
3x chicks ringed
09-06 chicks
g-T|A found and measured
14-06-2025 chicks
g-T|A found and measured

below: Caspian Gull cachinnans T|B 1CY, July 21 2025, IJmuiden, the Netherlands. Picture: Fred Cottaar.

below: Caspian Gull cachinnans T|B 1CY, June 30 2025, colony Lelystad, the Netherlands. Picture: Thijs Horst.

below: Caspian Gull cachinnans T|B 1CY, June 29 2025, colony Lelystad, the Netherlands. Picture: Thijs Horst.

First image: g-R|R & g-T|B.

below: Caspian Gull cachinnans T|B 1CY, May 13 2025, colony Lelystad, the Netherlands. Picture: Thijs Horst & Mars Muusse.

date darvic metal nest species sexe age wing mass head+ bill bill gonys barcode comments
13-5-2025 G-T|B .5641064 34 PONT   pullus   373         Ringed pullus