Yellow-legged Gull - Larus michahellis

(last update: October 08 2013)

Coordinators:
Delfín González
Gabriel Martín
Antonio Gutierrez
Amir Ben Dov
Mars Muusse

Yellow-legged Gull michahellis 1CY ILZB & IKZH September 20 & October 26 2002, Boulogne-sur-Mer, France.

A 1CY Yellow-legged Gull from Italy, ringed left blue ILZB. Note the extensive moult stage of this individual, compared to the average 1CY michahellis at Boulogne-sur-Mer. The upper two tertials are missing, the very tip of the first new tertial is already visible below the abraded scapular covert. The first two greater coverts have been replaced, #3 is growing, #4 is missing and #8 has been replaced. The complete median covert row will be replaced, with already most of the medians moulted. The same applies to the lesser and lower lesser coverts. The scapulars have been replaced for second generation feathers, except the lowest row of lower scapulars.

ILZB was seen again in Boulogne-sur-Mer on October 26 2002, with the advanced partial moult almost completed. Some wing-coverts were still growing, but most had been replaced. 
Moult score by the end of October: Tertials #1-4 are replaced and fully grown, greater coverts #1-4 are fully grown, #5 is still growing and #8 fully grown. Median coverts #1-10 are fully grown, lower lesser coverts #1-5 are fully grown, #6 is missing, #7-9 are fully grown and the outer lower lesser coverts from #10 outwards are growing. In the lesser coverts, four feathers are still missing but 70% of the visible area has been replaced, with still juvenile feathers in the outer tract (carpal edge). All moulted feathers are second generation now, feathers not mentioned are still juvenile.
All upper scapulars are second generation, the lower scapulars still have a few juvenile feathers. All tail-feathers are still juvenile. 
At a distance the bill is all dark, but close examination reveals a slightly paler base at the lower mandible.

The same day, October 26 2002, another 1CY michahellis from the same ringing project was found at Etaples, 20 km south of Boulogne: IKZH. (See bottom page).


ILZB, September 20 2002


ILZB, September 20 2002

Yellow-legged Gull (L. michahellis) IKZH (below)

October 26 2002, a 1CY michahellis from Italy, ringed blue IKZH, was  present at Etaples, NW France. This bird was pretty advanced in the partial autumn moult as well:
The upper tertials #1-3 are replaced, #4 is missing. Greater coverts #1-5 are fully grown and #6 is growing. Median coverts #1-5 are fully grown, #6-12 are growing. Lower lesser coverts #2-8 are fully grown, #9 and #11 are missing. 80% of the visible lesser coverts have been replaced for second generation feathers (about 15 feathers). All moulted feathers are second generation now, feathers not mentioned are still juvenile.
All secondaries and rectrices are still juvenile, all upper and lower scapulars are second generation feathers. The bill is all dark.

Gabbiano reale Larus michahellis IKZH C0087032
Pullus ringed on 14-05-02 at  Is. Maldiventre  (Cabras, Oristano) Italia 39,59N 08,18E by S. Nissardi

OBSERVATIONS:
26-10-02 Boulogne-sur-Mer (Pas-de-Calais) Francia 50,44N 01,36E

Gabbiano reale Larus michahellis ILZB C0094164
Pullus ringed on 14-05-02 at  Is. Maldiventre  (Cabras, Oristano) Italia 39,59N 08,18E by S. Nissardi

OBSERVATIONS:
31-07-02 Brouwersdam  Paesi Bassi  51,45N 03,50E
31-08-02 Boulogne-sur-Mer (Pas-de-Calais) Francia 50,44N 01,36E
20-09-02
Boulogne-sur-Mer (Pas-de-Calais) Francia 50,44N 01,36E
26-09-02
Boulogne-sur-Mer (Pas-de-Calais) Francia 50,44N 01,36E
26-10-02 Boulogne-sur-Mer (Pas-de-Calais) Francia 50,44N 01,36E