Category Archives: Black-headed Gull

Chroicocephalus ridibundus

22CY Black-headed Gull White LYD – 20180128

Primary covert variation in 1st-winter Black-headed Gulls

Reading ringed gulls in Leiden – 20171204

Reading ringed gulls in Leiden and Katwijk – 20171117

Black-headed Gull White ECM9 displaying courtship and territorial behaviour – 20170304

Return of the Black-headed Gull with an extra ‘foot’ – 20161211

Celebrating my 200th ringed Black-headed Gull and 1600 sightings in Leiden

1CY Black-headed Gull with an extra ‘foot’ – 20151226

1CY Black-headed Gull White EFJ5 – 20150625

Group effort: ring reading during sand suppletion activities at Scheveningen – 2015