first calendar year: July

General notes on 1cy LBBG July

In July many Dutch juvenile LBBG from early brood are leaving the colonies. They spread to the sandy beaches near the colonies and disperse along the coast. Year 2003, the first juvenile LBBG arrived at June 30 at Westkapelle, the earliest date ever. At the beaches, 100's juveniles can be found, while in the colonies some nests still contain three young pulli. Some juveniles already start moulting the upper scapulars.

2001-2002: indication of 2nd generation feathers

Year 2001 and 2002 we checked adult LBBG in the Maasvlakte and Dintelhaven colony. While doing our surveys, we noticed several juveniles with (what we though to be) second generation scapulars and wing-coverts. Such early replacement of wing-coverts was not described in current literature. The young were still begging at their parents for food within the colony. This was the reason for starting a more intensive research. The tables below present two surveys, initializing our 2004 research.

1cy LBBG research 2004

The first draft version (February 2004) can be found in the May section. The goals we described in this first draft appeared difficult to reach, so during the breeding season, several changes were made. First, we didn't start the ADULT LBBG research at Maasvlakte and Dintelhaven (Europoort). We postponed it and cooperated on that research with Roland-Jan Buijs, who is working in the LBBG colony at Moerdijk.

Next change: we couldn't continue to check the nests of the "100 group" (early breeders) three times a week. The impact of predation in the dense parts of the colony appeared to be unacceptable. So we followed the developments of marked nests from within a car and pulli were only measured once a week.

More information about the results of the 1cy LBBG survey will follow soon...

Tables 1cy LBBG June: