SOOTY TT 
HOWLAKD 
breeding data 
■ 1 * 
<* i v 
ti 
3 » * » • • • 
March 19 , 1963 - Wirtz: "There is a large sooty tern colony toward the northern 
i 
end of the island, certainly several thousand* The majority of 
the chicks are fledged hut few are flying. 
•March 21 , 1963 .- Wirtz: “This morning we took hlood samples from immature 
sooty terns and handed 300 of them* Tonight we hied., adults and 
handed 300 more immatures/” 
S' 
July 5- 8 , 1963 -- Sibley: "Several thousand over island in evening* hone on 
ground *" 
October 9-1^ - Sibley: "Several thousand flying and calling over island every 
evening, 
tt 
February 8-13, if 6 a —- Sibley: " 10 - 15,000 over the island in the evenings. Mostly 
over the north end." 
July 22-25» 1964 -*****«- Sibley summary : 11 1400 nestlings and 1000 adults banded® 
Estimated 5®,000 adults and 10,000 nestlings* Numerous 
youg birds flying around® Major colony on SB corner* 
A smaller group had just finished fledging on the west side® 11 
Hack mm 1 11 Tonight as we banded Sooty Tern® 1 noticed that the 
colony was distinctly composed of three groups (l) bird® with 
nearly fledged nestlings (2) birds with X«5 day old chicks 
(3) birds on half incubated eggs« (???~ Coes this sort of 
data which recurs through the Phoenix notes* and the unusual cycles 
not to mention the returns (in ter island breeders) occurring tend 
to indicate some mechanism by which groups of Bootle® breed when 
certain proximate features such as perhaps flock sis© are 
reached determine (Bonne bothered me — Forget it©} HB0 
