nominate Lesser Black-backed Gull (L. f. fuscus)

(last update: 30-12-2009)

Larus fuscus fuscus 4+cy J009, June 21 2005, Froholmen, Troms, Norway. Picture: Morten Helberg.

J009, illustrates the upper-part grey tone as can be found in approximately 50% of the breeding adults on the island of Froholmen. It looks like blackish nominate fuscus. The other 50% looks like pale-mantled birds as shown by J004, which was caught the previous day. As expected, complete moult still not started by mid-June, contrary J004.

The ringing programme at Froholman started in 2005 and within three years (2005-2007) 8 adults were caught on the nest. The catches of juveniles were better, with 162 juveniles colour ringed in the period 2005-2008; although last year only 2 birds were caught. 2008 has been a dramatic year regarding juveniles in all north Norwegian populations. None of the adults have been rediscovered outside the breeding range, up to May 2008, but three juveniles were seen again.

One of these birds is shown here as well, J916. This bird was seen in Israel and one year later in Egypt, nicely demonstrating the migration route already known for nominate fuscus from Finland. When J916 turned up in Egypt in February 2008 as 3cy bird, the upper-part grey tone was very dark, supporting the idea this is an offspring of pure fuscus.

More information about migration strategies in Norwegian fuscus and the ringing programme in the three northern counties of Norway: Nordland, Troms and Finnmark, can be found here: The summary for juveniles can be found in the fuscus 1cy October section, the summary for adults can be found in the fuscus adult October section.
Morten Helberg, Geir Systad, Ingve Birkeland, Nils Lorentzen & Jan Bustnes published an article about this research in Ardea 97, 2009, titled: Migration patterns of adult and juvenile Lesser Black-backed Gulls Larus fuscus from northern Norway. The complete PDF can be found HERE.