Larus cachinnans in the Netherlands

(last update: August 16, 2020)

Coordinator:
Albert de Jong
Merijn Loeve
Roland-Jan Buijs
Leon Kelder
Mars Muusse

Home

Cachinnans - nest De Kreupel 02P4 / r-KG

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 on island "B", positioned at edge. Nest coded "B02" in season 2021.
  • Both parents are cachinnans. Female already ringed: red 02P4 from Poland. This Polish bird trapped and ringed r-KG in 2021.
location: April 9th, 2021. April 9th, 2021: male at nest. April 9th, 2021: partners at look-out.
 
eggs: April 9th, 2021. April 9th, 2021. .
   
partner 1: April 10th, 2020: female r[02P4]. June 21st, 2020: female r[02P4]. .
   
  April 9th, 2021: female r[02P4]. May 14th, 2021: female r-K.G. April 23rd, 2021: female r-K.G (more images).
 
partner 2: April 10th, 2020: both partners. June 21st, 2020: male.  
   
  May 14th, 2021: male. June 17th, 2021: male.  
   
pulli May 21st, 2020: pullus p[F1]. May 21st, 2020: pullus p[F1]. June 26th, 2020 pullus p[F1].
 
  May 21st, 2020: pullus p[F=]. May 21st, 2020: pullus p[F=]. .
   
  June 17th, 2021: juvenile b[D|G]. June 17th, 2021: juvenile b[D|G]. .
   
prey: May 14th, 2021: 5x Cormorant eggs   May 14th, 2021: 1x leg of pullus Grey-lagged Goose.
 

Visits and data.

date: egg no: width (mm): length (mm): volume (cm3):      comments:
10-4-2020 --           Two adults, including female from Poland.
               
8-5-2020 C 50,2 72,4 132,49     2 pulli & 1 egg; pulli ringed.
      WING: HEAD + BILL: BILL: WEIGHT:  
8-5-2020 pullus NLA 5.545.417 & p[F1] -- 51.1 19.9 75  
8-5-2020 pullus NLA 5.545.418 -- 50.6 19.8 69 Too small for colour ring.
               
21-5-2020 pullus NLA 5.545.417 & p[F1] 100.0 90.7 38.1 558  
21-5-2020 pullus NLA 5.545.418 & p[F=] 98.0 89.4 37.1 517 Colour ring added.
21-5-2020 pullus NLA 5.545.432 83.5 85.7 36.0 440 New, probably C-chick.
             
12-6-2020 juvenile NLA 5.545.418 & p[F=]         B-chick p[F=] is dead.
     
26-6-2020 juveniles Two adults with two fledged juveniles.
             
date: egg no: width (mm): length (mm): volume (cm3):      comments:
9-4-2021 A egg 51.2 74.1       r[02P4] & unringed adult male at nest.
  B egg 49.0 67.2       3 eggs.
  C egg 51.1 78.7       https://waarneming.nl/observation/210425398/
     
23-4-2021 eggs 3 eggs in nest.
    Attempt to trap adult at nest. Successful: r[02P4] trapped and new ring attached.
    metal: tibia: wing (mm) head + bill tarsus bill
  adult Gdansk DN31202 Red-K.G 445.0 126.0 65.3 59.1
    mass (gr) Moult score bill height grey scale Swob  
    858 10x0 17.1 5.5 1083  
     
      WING: HEAD + BILL: TARSUS: MASS (gr):  
14-5-2021 pullus NLA 5.556.747 & b[D|E] 86.0 83.1 54.1 433 2 chicks outside nest, ringed.
  pullus NLA 5.556.748 & b[D|G] 73.0 82.5 54.8 439 No eggs. What happened to 3rd chick?
  prey 5x Cormorant eggs; 1x Coot egg; 1x leg of pullus Grey-lagged Goose. https://waarneming.nl/observation/214661741/
     
20-5-2021 pullus Shit traces all over the place, but chicks not found.
    Alarming adults over nest location.
     
17-6-2021 juvenile 2 juveniles near nest, one is b-D|G. https://waarneming.nl/observation/217412355/
  adult Unringed male & female r-K.G present.