So - 4 Auap tat ions of the &ltti"~ake 
to cl iff nesting compared with 
ground-nesting Gulls { j! ioa .ri inly 
on the Herring Gull and Bleckhended 
Gull). 
The territory is 1? r per. in lights 
the o*rds try to get on io-i of oppo- 
nent t nd pock down or tc „ .rub any 
part of him ? no pull backwarus. 
a 
Since the territory consists only 
of n sou 11 ledge, most fights et? rt 
on ledges. The birds attack mainly 
oy grabbing e< ch other’ s beak and 
then twisting hei'Ci. 
With specie-list tion to fighting by 
grasping bocks t re probably connec- 
ted; 
Yellon be; k strong at tack- releasing Beak Coes not release &t t ah oo 
stimulus. ^ strongly. 
Beak hidden in breast feathers in only turned i.\ t y irom 
i zi (.ppeasoment* vV^j^ nent in Appeasement, not hidden. 
Beak of the Young pitchblrck, of 
a distinct colour, seems not to 
be :t immature c .ring, beak \ ^ 
of young must prooably resemble - 
as little as possible tnat of ’ • * 
1 Iusiae of cjouth nd tongue bright- «*•»“*“ '; Juth ®»» oa 0r ^‘ U £ 
ly coloured, shoen inn 11 threat- colours*. tongue taomu not to be. 
posture hidden in appeastita it Mouth open out no LI 
• ;, jiu sexual jostur.it such es f ood begging, t hr sut post urea, tongue never 
lifted and displayed, koubh not 
To suauBrrize: important o csl closed in foodbeggln*£ Then uttering 
stimuli concentrated on beak and cell. 
eouti.. "' V — £ " JMtr-" ’ ' 
~ r r 
lie k oi Ycun .5 dark brot.n or block- 
ish with pinkish patch ■ t ti , eo- 
)ur seams not to b® special is dU 
Choking i e song. 
ing not sor;; . 
— - ■ ■ . 
A biru performing the aerial threat,, 
display d crlbes roughl Ht l 
circle in front of the cliffs, it 
achieves - 1. course by Ch aging its jPjjiT 
direction regularly in one ph sc oi C&ufwUt ^ ,<fi 
the display. • j 
Social collecting of nest-ms terii 1 
- , 
in the i - oriel display the, oirus 
fly in • more or less straight 
line over the colony. 
Mud cs nest-sat toriul. 
The ^individuals collect xons. 
lu£. /)*.umjU44*> - 
0 »i].y reads, dry .;rs 3 s etc. 
jtu, tenu GT JU#~ 
