390 LAKIM: 



AVERAGE MEASUREMENTS. 



TOTAL LENGTH ... ... 15'5 in. 



WING 9-25 



BEAK 1-9 



TAESO-METATARSUS 0'87 ,, 



EGG 1-7 x 1-15 in. 



COMMON TERN. Sterna fluvialitis (Naumann). 



Coloured Figures. Gould, ' Birds of Great Britain,' vol. v, pi. 

 70 ; Dresser, ' Birds of Europe,' vol. viii, pi. 580 ; Lilford, 

 ' Coloured Figures,' vol. vi, pi. 8. 



The Common Tern, familiarly known as the ' Sea- 

 swallow,' is plentifully distributed in summer along our 

 coasts, and about the shores and islands of inland lakes. 

 On the whole, it is probably the most abundant of British 

 Terns, though the succeeding species predominates on the 

 coasts and marine islands of North Britain, and is also 

 the most numerous in Ireland. North of the Moray Firth 

 on the east, and of the Island of Skye on the west of 

 Scotland, it becomes much scarcer, and previous to the 

 year 1901 there was no substantiated evidence to show 

 that it bred in the Shetlands (Eagle Clarke, Ann. Scot. 

 Nat. Hist., 1902, p. 121). In the Orkneys and Outer 

 Hebrides colonies are now known to exist. 



The majority of Common Terns reach us about the end 

 of April or beginning of May, departing gradually during 

 August and September for more southern latitudes. During 

 early October, limited numbers pass along the British coasts, 

 while I have seen a few solitary birds on inland waters at 

 that time of year. In the autumn, young and old consort 

 together, flying for miles along the coast in pursuit of the 

 ' schools ' of herring- and mackerel-fry. 



Flight. Most of us have seen these beautiful and 

 clamorous birds wing their way, some by the edge of the 

 breakers, others further out from the shore. One after 

 another, they poise with quivering pinions, hovering like 

 Kestrels, searching for their prey which moves beneath 

 them. 



What keen sight they must possess, seeing as they can, 

 the little fish under the surface of the water ! Like minia- 

 ture Gannets they precipitate themselves fearlessly with a 



