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Roughly a threefold increase in birds was noted during the present cruise 
over last month* Density (birds/linear mile) rose from 1*91 in March to 8.22 
in April. This increase has been gradual since the low of 1.15 recorded in 
November-December 1965. There was some increase in practically all species 
groups, but roost significantly in terns (almost exclusively Sooty Terns). 
Frigatebirds also showed a considerable increase. The start of a new breeding 
cycle on Howland Island is almost certainly the reason for increased numbers 
of birds in the area. 
. 
. 
Two peak days were noted. On April 7 W-SW of Howland, 1,314 birds were 
recorded. Most of these were in feeding or traveling flocks; 92.2 % terns, 
0.2 % Shearwater-Petrel. On 9 April practically the entire day was spent in 
close proximity to Baker Island (up to 12 miles distant) where large concen¬ 
trations of Sooty Terns and lesser numbers of other species were encountered. 
A total of 1,406 birds were recorded. Practically all were in feeding flocks; 
87 % terns, 0*6 7. shearwater-petrels. Large schools of milling fish were 
noted under feeding flocks. A total of 76 birds was collected throughout 
the day, primarily Sooty Terns. A Sooty Tern and a Red-footed Booby, both 
banded on Howland, were collected and a blue streamered Blue-faced Booby 
was noted. One Enderbury-banded Red-footed Booby was also collected. Although 
the direct evidence is meager, one must postulate that these concentrations 
were Howland-based birds. The exact stage of the breeding cycle of Sooty 
Terns is not known since no landing was made on Howland Island, but from 
behavioral observations and specimens collected offshore at night, the colony 
appears to be in or very close to the egg-laying stage. 
