The Tribe of the Sea Swallows 



Between the common and Arctic terns only small differ- 

 ences exist, so much so that it is a matter of great difliculty 

 to distinguish them on the wing. But I think there is a 

 well-marked difference in the call-notes of these two birds 

 which has not in the past been sufficiently emphasised. The 

 cry of the common tern is, generally, two or three sharp 

 notes, followed by a long-drawn and harsh scream. The 

 call of the Arctic tern is not long-drawn, but a very sharp 

 and piercing screech, oft-repeated while the intruder is 

 in the neighbourhood of the nest. When the two species 

 nest together, as is often the case, this difference in the 

 call-notes should, I think, serve to distinguish them. 



Then there is that small and active member of the tribe, 

 the lesser tern, much less common than either of the above, 

 but very charming in its habits, and confiding in its ways. 



The tribe of the sea swallows are, with the petrels, the last 

 birds to commence their domestic affairs, for they are de- 

 pendent for their food on the multitude of small fry — sand eels 

 and the like — which live in the surface waters of the sea, and 

 until the strong sunshine has warmed these waters the fry do 

 not make their appearance. 



The longest day is past, and full summer come to the 

 land of the hills and the lochs ere the sea swallows are in 

 the midst of their nesting. But even with midsummer the 

 air is not always warm, and the north-easter blows cold over 

 the face of the waters. One such day I crossed the Sound 

 of Gunna — that strip of tide-torn water lying between the 

 islands of Tiree and Coll — and saw many of the sea swallows 

 at their nesting. The sky was clear, this day of late June, 

 but the north wind was strong and keen, so that the sound 

 was wave-flecked, and the track of the tide, hurrying north- 

 ward against the wind, could plainly be seen bv reason of 

 the heavy sea which it was raising. Many islands lie in 

 the Sound of Gunna. Of all sizes are thev, ranging from 

 wide grassy slopes where highland cattle feed, to small 

 bare rocks scarcely showing above the water at the top of 



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