Notes from North IloUaml. 1G5 



parties of from 5 to 20 or more woulJ break off froni the main 

 flock, and by these parties following one anotlier in rapid 

 succession to some chosen feeding-groiind or resting-place the 

 whole flock, numbering many thousands, would shift its ground 

 without the casual observer being aware of the fact. Now as 

 I found this to apply without exception to every species observed, 

 whether belonging to the Passeres, Limicolse, or Laridae, and 

 as all the flocks of birds seen Coming in from the sea were in 

 small parties, it seems to me probable that migration is usually 

 undertaken in small flocks travelling in quick succession, and 

 this will probably explain the fact that so little migration is 

 generally seen. The enormous numbers recorded from light- 

 houses and other places from time to tinie are easily accounted 

 for by all the various parties stopping near the same spot, either 

 from weariness after a sea-passage or owing to the attraction 

 of the light due to stress of weather or some other cause. 



As further confirmation that birds travel in small parties my 

 notes on the Spooiibills are to the point. On the day of my 

 arrival I w^as able to count a flock of ^& individuals, and as 

 these birds always congregate together and are very conspicnous 

 it is unlikely that there were any more on the Island. Three 

 days later this flock was reduced to 50, two days after that to 

 12, and the following day to 4, after which no more were 

 observed with the exception of three stragglers a week or so 

 later. We are therefore entitled to presume that the first 

 flock of ^& individuals journeyed to the south in three or more 

 small parties. I should, of course, mention that my point of 

 Observation was their summer feeding-ground. 



]n collecting and observing birds during their migration I 

 had often beeil strack with the well-known fact that birds on 

 their journey are usually exceedingly fat, so mucli so that it 

 seems very doubtful to my mind whether they could live for 

 any length of time in such a condition. On the olher hand, I 

 also found many birds, irrespective of age, sex, or species, with 

 little or no fat as well as others in intermediate stages. To 

 this subject I paid considerable attention and found almost 

 invariably (though there were one or two exceptions, with which 

 I will deal later) that when the birds first arrived they were 

 thiii, and that at such tinios they would be moderately tarne and 



