first calendar year: July

Last update of this page: 01-08-05 08:53

General notes on 1cy LBBG July

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

1cy LBBG research 2004: 2nd generation feathers in juveniles

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, while the young were still begging at their parents for food within the colony, was the reason for starting a more intensive research. The tables below present some surveys, which initialized our 2004 research.

Tables:

 

new and/or missing mantle, scapulars, coverts and tertials in (still begging) juvenile LBBG in the Maasvlakte colony 16.08.2001 (n=32).
mantle	scaps	covs/tertials	#
0	0	0	4
?	0	0	8
0	1-5	0	2
?	1-5	0	7
0	6-10	0	2
1-5	1-5	0	1
1-5	1-5	1-5	3
?	1-5	1-5	1
0	6-10	1-5	3
?	6-10	1-5	1