MOVEMENTS OF THE CAN NET AT THE BUTT OF LEWIS 55 



MOVEMENTS OF THE GANNET AS OBSERVED 



AT THE BUTT OF LEWIS. 



By Robert Clyne. 



An eight years' residence at the northern promontory of the 

 Lewis has in no wise lessened the writer's interest in the 

 wonderful procession of Gannet life which all summer 

 continues to pass east and west in close proximity. As a 

 means of gaining further knowledge, or arriving at some 

 conclusion as to the why and wherefore of the movements, a 

 special observation and recdrd has been kept during the past 

 summer (191 5). From previous observations at other 

 outlying points we know that at certain periods of the year 

 vast numbers of Gannets pass along the coast, usually 

 following out and in the contour of the land, but here there 

 is during the summer months a daily passing of thousands. 

 The explanation of a well-known naturalist that the Gannets 

 "follow the shoals of herring and mackerel," does not, in my 

 opinion, satisfactorily solve the problem as regards this 

 particular locality. 



The Butt of Lewis being the extreme turning point 

 or gateway from the Minch to the open West Atlantic, and 

 centrally situated between the gannetries of St Kilda, 

 Sulesgeir, and Stack of Skerry, is doubtless the reason for so 

 many passing, but leaves us none the wiser as to whether 

 they are St Kilda or Stack Gannets, nor. what necessitates 

 their quest so far afield. From the Butt, St Kilda is about 

 90 miles S.W., Sulesgeir about 30 north, and the Stack about 

 65 in a N.N.E. direction. At these gannetries J. H. 

 Gurney in his interesting book on the Gannet gives the 

 number of birds approximately as 30,000 at the St 

 Kilda group of islets, and 8000 at each of the other two 

 places. A compulsory close season of the herring fishing in 

 this district did not to any extent affect the number of 

 Gannets passing. They were seen earlier and more 

 numerous in January 191 5 than usual, then occurred a blank 

 for two weeks, before a gradual and continued increase 

 of passing birds set in. So numerous and continuous were 



