Lesser Black-backed Gull (graellsii & intermedius)

(last update: May 17 2015)

LBBG 1cy E74 , June 25 - August 06 2004, Maasvlakte, the Netherlands. 

Nest 399, C-young. Bird still tie wrapped, not darvic ringed on June 18 2004 (July 11 2004). Caught today for measurements. All coverts still juvenile in right wing.

LBBG 1cy E74E & E76E,July 13 2004, Maasvlakte, the Netherlands.

Both birds, from the same nests, still in juvenile plumage. No sign of malnutrition or virus / bacterial infection.

Below: LBBG 1cy E74E & E76E,July 13 2004, Maasvlakte, the Netherlands.

First sign of malnutrition or virus / bacterial infection. E76 has missing coverts in the right wing. Note missing feathers in the side-neck. Primaries fully grown, P10 > P9.

LBBG 1cyE74E &E76E August 06 2004, ECT, Maasvlakte, the Netherlands.

Two birds ringed left red E74 & E76, right yellow E, from the same nest, with three fledged juveniles. E75, not in the picture, fledged as healthy young, in complete juvenile plumage. These two birds, E74 & E76, appeared to have been infected by some kind of virus or other illness. The impact is clearly visible in the rear wing and back of the birds. Outer primaries, except P10 were dropped, the complete tail is missing, and several feather tracts are heavily influenced. Some lower tertials are growing again in E76, now second generation feathers and later this month, the outer primaries were replaced as well, second generation feathers as well.