152 The Irish Naturalist, [June, 



second week of May, and althoug^i I have long observed 

 them about the locality, it was only of late years that I have 

 ascertained their breeding-haunt on the Inch, between Killala 

 and Bartragh (their only breeding-haunt on the North Mayo 

 coast). Here a small colony of ten or twelve pairs, used to 

 breed in company with Common and Arctic Terns, until the 

 past summer of 1895, when their numbers suddenly, and most 

 unaccountably increased, and as they had not sufficient scope 

 on the gravelly Inch, they spread over the adjacent sandy 

 peninsula of Ross. When I visited the Inch on the 14th of 

 last June, I was surprised at the large numbers of these terns, 

 and estimated that at least 60 to 70 pairs were seen all about — 

 both on the wing, resting on the sands,and sitting on their eggs, 

 The birds had spread along the Ross shore for nearly half a 

 mile laying their eggs on the sandy flat, and round the gravelly 

 base of some hillocks, from which the sand had been blown 

 away ; no nests had been made ; the two or three eggs of each 

 pair lay on the bare sand or gravel. Just across the narrow 

 channel, on the extreme end of Bartra Island, I found four 

 pairs hatching a little above high water mark, and below 

 the line of Bent-grass, the eggs also on the bare sand, and 

 where no birds had ever before been known to breed. 



The sudden increase of this tern is very interesting and 

 mysterious, for it cannot be accounted for by any larger 

 number than usual having been reared on the Inch the 

 previous summer. Unless by the desertion of some distant 

 breeding-haunt it is difficult to account for this influx of 

 breeding birds to the Inch and neighbourhood. Besides this 

 North Mayo breeding-haunt, there are several along the Sligo 

 coast ; one at Rosses Point, Sligo Bay, where a small colony 

 of eight or ten pairs frequent a little sandy ba}^ off the Rabbit- 

 burrows, another on the northern side of the point in Drum- 

 clifie Bay, where thirt}' to forty pairs breed on the wide ex- 

 panse of sand-flat, which extends nearly across the upper end 

 of .the bay. This wide expanse of sand is generally bare all 

 the summer, and apparently is only covered by the high spring- 

 tides of spring and autumn ; so the terns can hatch and rear 

 their young in safety, for as they lay near the centre of the 

 flat nearly a mile from the land, they are seldom molested, 

 being quite out of the way of either cockle-pickers or bait- 

 diggers. A third breeding^haunt is situated three or four 



