400 



Scotland and Ireland accommodate small colonies. The 

 numbers of Little Terns which haunt certain nesting- 

 districts are liable to fluctuate considerably every year. 



I am aware of several nesting-sites on the British coast, 

 where during one season the number of birds has been 

 treble that of the preceding year, while in another locality 

 I have known a colony of forty pairs to be represented by 

 only about twelve birds in the two ensuing years, and after 

 that the numbers to rise again to more than sixty birds. 



Geographical distribution. Beyond our Isles the Little 

 Tern is found nesting in Temperate Europe from lat. 60 N. 

 down to the Mediterranean. It also breeds in North Africa, 

 and in Asia as far as India. On migration, it visits the 

 coasts of Southern Africa and Asia. 



DESCRIPTIVE CHARACTERS. 



PLUMAGE. Adult male nuptial. Forehead, white ; top 

 of head and back of neck, black ; a broad black stripe 

 extends in front of and behind the eye ; back, scapulars, and 

 wings, ' pearl ' grey ; primaries, grey, margined on the inner 

 webs with white ; two outer primaries have dark shafts ; 

 throat, breast, abdomen, and tail, white. 



Adult female nuptial. Similar to the male plumage, but 

 the outer tail-feathers are shorter than in the male. 



Adult winter, male and female. The black on the head 

 is much duller in colour, and there is more white on the 

 forehead than in the nuptial plumage. 



Immature, male and female. Top of head and back of 

 neck, tinged with pale yellowish-buff and streaked with 

 dark brown ; back, scapulars, and wings, grey, tinged with 

 buff and mottled with umber-brown ; tail-feathers, greyish- 

 white, slightly spotted with brown near the tips. 



The mature plumage is gradually assumed, breeding not 

 taking place until the completion of the third year. 



BEAK. Yellow, with dark brown tip. 



FEET. Yellow. 



IRIDES. Blackish-brown. 



AVERAGE MEASUREMENTS. 



TOTAL LENGTH ... 10 in. Female a little smaller. 



WING 6-75 



BEAK ... ... 1*5 ,, 



TARSO-METATARSUS 0'75 ,, 



EGG 1-35 x '95 in. 



