Clare Island Survey — Aves. SO 43 



the water by light-keepers as late as 14th November. They lay on The 

 Bills iii moderate numbers, and in all directions along the cliff's of north 

 Mayo, as well as in the great sea-bird colonies round Ireland. 



Uria grylle(Linu.). Black Guillemot. — A good many scattered birds observed, 

 April-July, about the west and north shores of Clare Island, in Achill 

 Sound, among the islands of Clew Bay, and round the Mullet, where 

 they are often observed by Wallace in winter. Shores strewn with 

 boulders offer cover for this bird to breed apart from other species. It 

 is frequent in the inlets of the coast of north Mayo and Connemara, and 

 many frequent High Island (Witherby), but not in colonies. 



Mergulus alle ( Linn.). Little Auk. — -Met with occasionally after fierce winter 

 storms, when it is sometimes cast ashore on many parts of the Mayo 

 coast, including Achill and Black Rock. Save as above, it is a bird of rare 

 occurrence in Ireland, and occurs most frequently in the north and 

 north-west. 



Fratercula arctica (Linn.). Puffin. — Considerable colonies extend along 

 the upper parts of the Clare Island cliffs among and above those of 

 Razorbills. They have no rabbit-holes to occupy, so they must dig their 

 own burrows. They sometimes fight beak to beak, as though one were 

 trying to take fish from the other, without pulling out feathers (Patten). 

 Barrington saw none the last week in March, but Barrett-Hamilton noticed 

 some on 10th April. On the eastern island of The Bills (Plate III) the 

 whole of the peaty surface is simply riddled with burrows of Puffins, 

 which are exceedingly numerous (Praeger). On the north Mayo coast 

 the speciality is the great colonies of Puffins which reach up to the cliff- 

 tops, over "700 feet high in places, and the sloping grassy tops of the 

 Stags and Moistha (" Illanmaster ") have a dense, teeming population of 

 these birds. 



Colymbus glacialis, Linn. Great Northern Diver. — Haunts the coast and 

 bays most of the year up to June, when there is a northward migration 

 through Achill Sound ; and Wallace has shown Ussher a bird on 4th 

 June flying high from Blacksod Bay towards Broadhaven. McCabe has 

 a specimen shot on Clare Island, where it is commonly seen. Good has 

 seen this Diver on Lough Corrib and generally on Lough Mask. It has 

 been obtained in Donegal more than once in July, and has been seen in 

 Mayo as early as the first week in October (Good). 



Colymbus arcticus, Linn. Black-throated Diver. — Has been obtained at 

 Achill (Sheridan), and identified on Killala Bay (Warren), but is 

 exceedingly rare. 



F2 



